About Rationally Speaking


Rationally Speaking is a blog maintained by Prof. Massimo Pigliucci, a philosopher at the City University of New York. The blog reflects the Enlightenment figure Marquis de Condorcet's idea of what a public intellectual (yes, we know, that's such a bad word) ought to be: someone who devotes himself to "the tracking down of prejudices in the hiding places where priests, the schools, the government, and all long-established institutions had gathered and protected them." You're welcome. Please notice that the contents of this blog can be reprinted under the standard Creative Commons license.

Thursday, January 30, 2014

Sean Carroll, Edge, and falsifiability

by Massimo Pigliucci

Cosmologist Sean Carroll is one of many who have recently answered the annual question posed by Edge.org, which this year was: What scientific idea is ready for retirement? Sean, whom I’ve met at the Naturalism workshop he organized not long ago, and for whom I have the highest respect both as a scientist and as a writer, picked “falsifiability.”

Which is odd, since the concept — as Sean knows very well — is not a scientific, but rather a philosophical one.

Now, contra some other skeptics of my acquaintance, at least one of whom was present at the above mentioned workshop, Sean is actually somewhat knowledgable and definitely respectful of philosophy of science, as is evident even in the Edge piece. Which means that what follows isn’t going to be yet another diatribe about scientism or borderline anti-intellectualism (phew!).

Rather, I’m interested in Sean’s short essay because he deals directly with the very subject matter I just covered in my recent post based on Jim Baggott’s thought provoking book, Farewell to Reality: How Modern Physics Has Betrayed the Search for Scientific Truth. 

Before we proceed, I should also point out that I’m not interested in debating physics with Sean, since he is the expert in that realm (if Jerry Coyne wants to debate evolutionary biology with me, that’s another matter…). Indeed, I’m happy to watch the ongoing conversation between Carroll (and others) and critics of some trends in contemporary theoretical physics (like Baggott, Lee Smolin and Peter Woit) from the outside — which is actually a pretty good job description for a philosopher of science.

Rather, I’m interested in the philosophical aspects of Sean’s Edge essay and in what they say about his conception of science. I have, of course, invited Sean to respond to this post, if he wishes.

Sean begins the essay by attributing the idea of falsificationism to philosopher Karl Popper, correctly framing it within the broader issue of demarcationism (in this case, between science and pseudoscience). Sean immediately points out that demarcationism, while “a well-meaning idea” is “a blunt instrument” when it comes to separating scientific from non-scientific theorizing, and he is right about that.

Indeed, trouble for Popper’s view began even before it was fully articulated, by means of physicist-inclined-toward-philosophy Pierre Duhem, who raised exactly the same objections that Sean summarizes in his Edge piece. Fundamentally, Duhem noted that in actual scientific practice there is a complex relationship between theory and observation or experiment (what philosophers refer to as the theory-ladeness of empirical results), so that any given set of empirical data (say, from a particle accelerator experiment) doesn’t strictly speaking test the theory itself, but rather a complex web of notions that comprise the focal theory (say, the Standard Model), a number of corollary theories and assumptions needed to build it, as well as assumptions about the correct functionality of the measurement instrument, the way the data are analyzed, and so on. If there is a mismatch, Duhem argued, scientists don’t immediately throw away the theory. Indeed, the first thing they are likely to do is to check the calculations and the instrumentation, moving then to the auxiliary assumptions, and only after repeated failures under different conditions finally abandon the theory (if they had strong reasons to take the theory seriously to begin with).

Later on during the middle part of the 20th century, influential philosopher W.V.O. Quine expanded Duhem’s analysis into what is now known as the Duhem-Quine thesis: scientific (or really, any) knowledge is the result of a complex web of interconnected beliefs, which include not just the elements mentioned by Duhem (i.e., those most closely connected to the theory under scrutiny), but also far removed notions about the world and how it works, up to and including mathematics and logic itself.

This should not be taken as counsel for despair: scientific theories still can, and regularly are, tested. But if we are to speak precisely, what we are testing every time is our entire web of knowledge. If something goes wrong, the problem could in principle reside anywhere in the web. It is then up to clever and creative scientists to focus on the most likely culprits, eliminate the ones they can, and eventually reach a consensus as a community regarding the soundness of the theory being “tested.” That’s why science is just as much an art as a logical pursuit.

So far so good. Sean then proceeds to state that “String theory and other approaches to quantum gravity involve phenomena that are likely to manifest themselves only at energies enormously higher than anything we have access to here on Earth. The cosmological multiverse and the many-worlds interpretation of quantum mechanics posit other realms that are impossible for us to access directly. Some scientists, leaning on Popper, have suggested that these theories are non-scientific because they are not falsifiable.”

If some scientists have indeed leveraged Popper in order to criticize string theory, the multiverse and all the other speculative ideas of modern theoretical physics, those scientists really ought to take my Philosophy of Science 101 course before they write another line on the subject. But I think the problem is actually a bit more complex and nuanced than Sean leads his readers to believe.

He continues: “The truth is the opposite. Whether or not we can observe them directly, the entities involved in these theories are either real or they are not. Refusing to contemplate their possible existence on the grounds of some a priori principle, even though they might play a crucial role in how the world works, is as non-scientific as it gets.”

Well, not exactly. To begin with, I sincerely doubt that critics of those theories refuse to contemplate the existence of strings, branes, and the like. Their point, rather, is that these hypothetical entities (“unobservables” in the lingo of philosophy of science) have in fact been contemplated, for decades, and so far nothing much has come out of it, empirically speaking. After all, Smolin, Woit, and Baggott observe, physics is a science, and science is supposed to make contact with the empirical world, at some point. The longer a theory fails to do so, the more problematic it ought to be considered. That’s all.

Sean does provide his own rough alternative to falsifiability. He claims that two central features of any scientific theory are that they are definite and that they are empirical. While there is a lot more to be said about the nature of scientific theorizing (and yes, I understand that Sean is not a philosopher of science, and moreover that Edge probably strictly limits the length of the responses it seeks) let’s go with it for a moment.

Sean says that “by ‘definite’ we simply mean that they say something clear and unambiguous about how reality functions.” He argues that string theory does precisely that, insofar as it says that in certain regions of parameter space particles behave as one-dimensional strings. He is right, of course, but the criterion is far too inclusive. For instance, someone could argue that the statement “God is a conscious being or entity who exists outside of time and space” is also quite “definite.” We all understand what this means, ironically especially after modern physics has actually helped us make sense of what it may mean to be “outside of time and space.” Whatever “was” “there” before the Big Bang was, from the point of view of our universe, outside (our) time and (our) space. So, to say something definite (as opposed to something postmodernistically nonsensical) is certainly a good thing, but it ain’t enough to pinpoint good scientific theories.

What about the empirical part? Here is, according to Sean, where the smelly stuff hits the fan. As mentioned above, he rejects a straightforward application of the principle of falsifiability, for reasons similar to those brought up so long ago by Duhem. But what then? Sean mentions some examples of what Baggott calls “fairy tale physics,” such as the idea of a multiverse. His strategy is interesting, and revealing. He begins by stating that the multiverse offers a potential solution to the problem of fine tuning in cosmology, i.e. the question of why so many physical constants seem to have taken values that appear to be uncannily tailored to produce a universe “friendly” to life. (I actually think that people who seriously maintain that this universe is friendly to life haven’t gotten around much in our galactic neighborhood, but that’s a different story.)

He continues: “If the universe we see around us is the only one there is, the vacuum energy is a unique constant of nature, and we are faced with the problem of explaining it. If, on the other hand, we live in a multiverse, the vacuum energy could be completely different in different regions, and an explanation suggests itself immediately: in regions where the vacuum energy is much larger, conditions are inhospitable to the existence of life. There is therefore a selection effect, and we should predict a small value of the vacuum energy. Indeed, using this precise reasoning, Steven Weinberg did predict the value of the vacuum energy, long before the acceleration of the universe was discovered.”

Notice two problems here: first, according to Baggott, Weinberg’s prediciton was a matter of straightforward (if brilliant) physics, and it was conceptually independent of the fine tuning problem. The same goes a fortiori for another famous prediction, by Fred Hoyle back in the ‘50s, about the cosmic production of carbon. That one, which is nowadays often trumpeted as an example of how science has advanced by deploying the anthropic principle, was actually put forth (and confirmed empirically) before the very idea of an anthropic principle was formulated in the ‘60s.

More crucially, again as pointed out by Baggott, the reasoning basically boils down to: we have this empirically unsubstantiated but nice theoretical complex (the multiverse) that would very nicely solve this nagging fine tuning problem, so we think the theoretical complex is on the mark. This is dangerously close to being circular reasoning. The fact, if it is a fact, that the idea of a multiverse may help us with cosmological fine tuning is not evidence or reason in favor of the multiverse itself. The latter needs to stand on its own.

And yet Sean comes perilously close to proposing just that: “We can't (as far as we know) observe other parts of the multiverse directly. But their existence has a dramatic effect on how we account for the data in the part of the multiverse we do observe.” I truly don’t think I’m reading him uncharitably here, and again, I’m not the only one to read some cosmologists’ statements in this fashion.

None of the above should be construed as suggesting that ideas like the multiverse or string theory are somehow pseudoscientific. They are complex, elegant speculations somewhat grounded in well established physics. Nor is anyone suggesting that barriers be put around the work or imagination of cosmologists and string theorists. Go ahead, knock yourselves out and surprise and astonish the rest of us. But at some point the fundamental physics community might want to ask itself whether it has crossed into territory that begins to look a lot more like metaphysics than physics. And this comes from someone who doesn’t think metaphysics is a dirty word…

115 comments:

  1. Very well said. Particularly the point that most of the critics of these theories aren't saying they shouldn't be contemplated, only that the metaphysical nature, the speculative nature of them, should be kept in mind. They should be kept in a different category from theories that are well attested by experimental observation.

    Most notably when considering the strength or weaknesses of other physics theories in relation to how well they comport with these speculative theories. Baggott, in his book, points out some theories that had largely been discarded, but received a resurgence for no other reason than that they were compatible with some string theories. In other words, wild speculation was suddenly a little less wild because it was compatible with...other speculation.

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  2. What if, for all practical purposes, a theory that theoretically has empirical outputs can never be tested in a state to find those? Like us never spending the money to build the equipment and input the energy levels needed to look for empirical evidence of string theory? Do we then do a Husserl-type bracketing and call it a quasi-theory or something?

    ===

    And, as for replacing falsification, if you were to take your own shot at the issue, Massimo, what would you write up?

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  3. Massimo, given the methodological vs. metaphysical distinction in naturalism that you endorsed in Nonsense on Stilts and elsewhere in this blog, I wonder how common it is for scientists to cross that demarcation line. Perhaps this is another way to frame your objections to "scientism" (?)

    Anyhow, for reasons that I won't go into here, I harbor serious doubts about the value of metaphysics - including metaphysical naturalism.

    But suffice it to say that, so long as we are clear that we are dealing with a provisional and highly fallible area of speculation (e.g. based merely on inferences from finite human experience), rather than with a catechism of absolute infallible truths, I suppose that I can make peace with your use of "metaphysics" as a non-dirty word.

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  4. Two things here. First, Sean is, I think, right to distance himself from the Popperian notion of falsifiability (though, when scientists or those in the skeptics community use 'falsifiability', rarely do they have the strict Popperian concept in mind). In a very strict sense, probabilistic hypotheses, e.g. an hypothesis about the underlying probability distribution of some random variable, are not falsifiable since any sample observation is logically consistent with the hypothesized distribution: observing 25 heads in a row does not falsify our hypothesis that the coin is fair, though it nevertheless constitutes as strong disconfirmation, a concept which escapes Popper's technical machinery (Popper instead employed 'corroboration' as a ).

    This is especially problematic since much of our most cherished scientific enterprises – quantum statistical mechanics, genetics, etc. -- deals in probabilistic hypotheses and models. There are other problems with deductivism, too, but the above is probably the most serious. And, like Sean, I would LOVE for skeptics to stop bandying about Popper and 'falsification' (as an aside, your efforts to this end, Massimo, are admirable).

    Second, Massimo, I think your criticism of Sean's support for multiverse theories is a bit off base. When Sean writes:

    'We can't (as far as we know) observe other parts of the multiverse directly. But their existence has a dramatic effect on how we account for the data in the part of the multiverse we do observe,'

    it is not that we must construe him as arguing because various theoretical derivations, which entail multiverses, that help account for observable conditions in our universe that multiverses are thereby strongly confirmed. I think he is making a weaker claim, which goes something like this: 'Though we account for multiverses conjecturally and no experimental conditions present themselves for independent verifiability, that multiverses fall out of theories that have empirical support and which otherwise economize our cosmological models confers some measure of confirmation to the proposition that there are multiverses.'

    In other words, though we may want to obtain independent observational confirmation of multiverses (or strings) before we sign on to them, that such things are mathematical consequences of useful theories provides some minor confirmation to them. If this is what Sean claims, then his reasoning is not circular in Baggott warns.

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  5. You are very fair, Massimo.

    "If some scientists have indeed leveraged Popper in order to criticize string theory, the multiverse and all the other speculative ideas of modern theoretical physics, those scientists really ought to take my Philosophy of Science 101 course before they write another line on the subject."

    My impression is that many people (not necessarily scientists, just the general public) indeed accept falsificationism, and use it to criticize string theory. You can see this on the comments on Sean's own blog (http://www.preposterousuniverse.com/blog/2014/01/14/what-scientific-ideas-are-ready-for-retirement/).

    "This is dangerously close to being circular reasoning."

    IMO the accusation of "circular reasoning" applies to knowledge with a foundationalist structure, and not necessarily knowledge with a web structure. Any good web has lots of circles within. Circular reasoning is a check on self-consistency. Clearly though, circular reasoning is rather weak support by itself, so I don't mean to say that you are being unfair.

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  6. < I should also point out that I’m not interested in debating physics with Sean >
    And Sean would point out that any discussion of physics with you would be him teaching you, not a debate. I'm quite sure his work on the arrow of time applies to the section of this post related to the multiverse theory.

    < Their point, rather, is that these hypothetical entities (“unobservables” in the lingo of philosophy of science) have in fact been contemplated, for decades, and so far nothing much has come out of it, empirically speaking. >
    That is a limitation of our technology, not an indictment of the contemplations. In addition, the contemplations have produced entire new fields in pure math. Eventually, they too will make contact with the empirical world.

    < someone could argue that the statement “God is a conscious being or entity who exists outside of time and space” is also quite “definite.” >
    That would be a very poor argument. So bad I can't believe you proposed it. That statement says absolutely nothing about how reality works. And I would say it isn't clear what "outside of time and space" means in the sentence, especially because it certainly doesn't just apply to something "before" the Big Bang or outside our observable universe. Even "conscious being" is poorly formed. Come on, Massimo.

    < that the idea of a multiverse may help us with cosmological fine tuning is not evidence or reason in favor of the multiverse itself. The latter needs to stand on its own. >
    I'm sure Sean can talk about many different lines of evidence for why a multiverse stands on its own or not. He certainly isn't relying on solving fine tuning as evidence for the MV.

    I think you're off base on your approach here and a bit out of your depth on the physics. Sorry, but I still like you more than Jerry Coyne!

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    1. "That is a limitation of our technology, not an indictment of the contemplations. In addition, the contemplations have produced entire new fields in pure math. Eventually, they too will make contact with the empirical world."

      Maybe these new fields in pure math will turn out to be useful in theories that do make contact with the empirical world. But that wouldn't tell us anything about string theory as a fundamental theory of nature.

      I know this is philosophy blog, but I think that focussing on the philosophical aspects of string theory misses something. When physicists criticize string theory, there are usually two things in the background: a sociological aspect, and a comparison with other theories.

      First the sociological aspect. Quite a few physicists feel that string theory has been too dominant in the past twenty or thirty years. Too many resources and (often brilliant) people went into string theory. Other domains in theoretical and mathematical physics were suffering, or suspected that they were suffering.

      The comparison with other theories is usually in the background as well ; In spite of WWII, it took physicists about 40-50 yrs. to go from the first quantum field theories to the standard model. String theory is now approaching that age, and what does it have to offer? Multiverses? Interesting mathematics?

      There's another thing when you start to compare theories. The standard model is spectacularly succesful. Yet most physicists will agree that the theory has its problems, and that it would be strange if it were the ultimate word on nature (there's no unification with gravity etc.). String theory is, measured with the same standards, spectacularly unsuccesful. Moreover, it has its own problems, but some (not all) string theorists have an uncanny ability to turn these problems into strengths. Too many solutions? The anthropic principle! No contact with experiment? A limitation of our technology! It only show that the theory is truly fundamental! It describes phenomena on an energy scale as yet unexplored! It's the only game in town! Etc. etc.

      Many physicists - and I tend to agree - feel that, compared with other theories, string theory is judged with different standards. Quite lax standards, to be honest. If they try to articulate what they mean, they sometimes wander into philosophical territory (Popper etc.). The results are probably not always good philosophy.

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  7. Hi Massimo,

    An enjoyable article as always. Glad to see the old comment system reinstated.

    I find I am entirely sympathetic with Sean Carroll's point of view, but all the same most of what you say also seems reasonable to me. Where I don't call you out on a point, you can probably assume I'm with you.

    >Which is odd, since the concept — as Sean knows very well — is not a scientific, but rather a philosophical one.<

    You're nitpicking! It's a concept from philosophy of science. It pertains to science. It is scientific in that sense. If it's something he wants to write about, something that pertains to his work as a physicist, I wouldn't begrudge him a broad interpretation of the Edge topic.

    >For instance, someone could argue that the statement “God is a conscious being or entity who exists outside of time and space” is also quite “definite.” We all understand what this means<

    I don't know what it means. I think the statement about God is very much an example of what is not 'definite' in the sense Sean Carroll means. I'm not even sure what it means to say that a being is conscious! The sentence about strings, on the other hand, is just a quick summary of what is actually a very precise and mathematically well-developed field. No amount of theological waffling about God or consciousness can compare.

    >was actually put forth (and confirmed empirically) before the very idea of an anthropic principle was formulated in the ‘60s<

    Anthropic arguments and anthropic thought surely existed before the concept was codified, published and given a name. That does not mean that these were not applications of the anthropic principle.

    >we have this empirically unsubstantiated but nice theoretical complex (the multiverse) that would very nicely solve this nagging fine tuning problem, so we think the theoretical complex is on the mark. This is dangerously close to being circular reasoning.<

    I see no circularity there at all. I have this elegant theory of gravity that would very nicely unify the orbits of the planets and the behaviour of objects falling to earth, so I think my theory of gravity is on the mark.

    >The fact, if it is a fact, that the idea of a multiverse may help us with cosmological fine tuning is not evidence or reason in favor of the multiverse itself.<

    I don't see why not. It may not be tremendously strong evidence, but it is evidence to a point.

    >The latter needs to stand on its own.<

    Why?

    >But at some point the fundamental physics community might want to ask itself whether it has crossed into territory that begins to look a lot more like metaphysics than physics.<

    I don't think it looks that much like metaphysics. It at least has the potential of resulting in verifiable predictions. "Science is supposed to make contact with the empirical world, at some point", but who is to say when that point is?

    It may be different from other sciences in that there is a lot of work being done on unverified results. It straddles science, mathematics, and (only vaguely) metaphysics, and so though it may be drifting away from science in the strictest Popperian sense of the word, who actually cares? It's still valuable, worthwhile work that needs to be done, and they're doing a great job in my view. Let them at it, I say.

    If you don't want to call what they do "science", then fair enough. If we need a term to describe the work they do, I propose not "pseudoscience", not "metaphysics", but "theoretical physics".

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    1. "I see no circularity there at all. I have this elegant theory of gravity that would very nicely unify the orbits of the planets and the behaviour of objects falling to earth, so I think my theory of gravity is on the mark."

      It's true that planets have an orbit and objects fall to the earth. These are observational facts.

      However, the argument in string theory goes like this

      "we have this empirically unsubstantiated but nice theoretical complex that would very nicely solve this nagging fine tuning problem (**IF this theoretical complex were true**) so we think the theoretical complex is on the mark."

      If it's true, then it's true. I makes me think of psychoanalysis. Latent homosexuality would nicely explain the strange behavior of X towards his mother, therefore my theory of latent homosexuality is on the mark.




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    2. Hi Patrick,

      I enjoyed and agreed with what you said in your earlier comment, about how resources might be diverted towards string theory without merit, so I suspect our positions are not that far apart.

      With regard to your example, I am not persuaded. I do think that there is evidence for the latent homosexuality of X if there is no reason to doubt it and if it actually does account for X's behaviour towards his mother. It's just not necessarily very strong evidence. In particular, it's not strong if there are a priori reasons for doubting it or if the explanation for the behaviour is not very convincing. I don't think that is true of string theory or the multiverse.

      Besides, the multiverse does not depend on string theory. I think that the anthropic principle is a good reason to believe in a plurality of universes whether or not string theory happens to be true.

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    3. Disagreeable,

      Thank for your reply. Note that I left "(the multiverse)" out of the quote when I copied it. I agree that one doesn't need string theory for multiverse ideas.

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  8. "(if Jerry Coyne wants to debate evolutionary biology with me, that’s another matter…)"
    That would make for an excellent episode of Rationally Speaking.

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  9. I read this definition of "theory" on profmattstrassler.com (a blog by a theoretical physicist):

    “Theory”, in physics, means: a set of equations that can be used to make predictions for physical processes in a real or imaginary world.

    I'm not sure what is meant by an imaginary world, but it would seem to give theoretical physicists some room to roam.

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  10. It seems like the issue with string theory largely rests on how much more investment are we to reasonable put into it. We can easily imagine situations where string theory is "correct" and we are just technology limited and just as easily imagine that it's not true and when we get the technology we will find out it's not true. However, currently we can't know either way, all we know is that it's failed to make the progress that is typically expected from scientific inquiry. I have to admit that for this reason, I'm sympathetic with those who are critical of string theory, especially as it seemingly pulls in the brightest young physicists and has so little to show for it. At some point, we have to set it aside and maybe if the technology gets there, pick it back up. I'm sure there is no shortage of other areas physics can be exploring in the meantime.

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  11. Of course falsification was also intended in the context of a theory of meaning.

    A J Ayer's biggest complaint about Neurath was that his "Physicalism" proposal required a consistency theory of meaning. To me it looks like we are right back to what Neurath proposed.

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  12. >… But at some point the fundamental physics community might want to ask itself whether it has crossed into territory that begins to look a lot more like metaphysics than physics.<

    I think the physics community has been aware of these problems for some time, as well as being split and splintered in terms of subdisciplines, general approaches, etc.

    Even Neil Turok, who did much to develop – and promote – string theory in the past, talked openly last year about a crisis in theoretical physics and string theory in particular.

    But, though there is clearly a place for non-physicists in this debate (particularly on questions of public funding for the discipline and for particular physics-based projects (like the LHC)), I have the sense that much of the debate and discussion is motivated by a desire to score points against a high prestige discipline on the part of those who may be associated with disciplines (or subdisciplines) with a perceived lower status. Unfortunately, even serious and intellectually-motivated critiques like Massimo Pigliucci's latest pieces may be interpreted by many in this light.

    One last point. Massimo characterizes his position as a (non-physicist) philosopher of science as that of an interested observer. Doesn't such a stance – eminently reasonable as it is – raise some awkward questions about the efficacy of the philosophy of science and indeed metaphysics as independent disciplines, distinct from the sciences in question?

    I think that Massimo rejects traditional approaches to metaphysics and argues for a more scientifically-informed style of philosophizing. Which is fine as far as it goes.

    I guess I would want to take things just a little further in that general direction.

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  13. Which is odd, since the concept — as Sean knows very well — is not a scientific, but rather a philosophical one.

    I have mixed feelings about this. On the one hand, I thought exactly the same about a great many of the other topics on Edge. On the other hand, falsifiability of all things? Yes, that one is a scientific concept; if it isn't, then there are no scientific concepts.

    This is your usual argument: the moment a scientist uses something like Occam's Razor for example, you conclude that they have cheated and are really doing philosophy. But it cannot work like that. If I am a blacksmith, make a hammer and sell it to a carpenter, then I don't get to say that the carpenter is doing blacksmithing with it. Yes, the hammer has been provided by a smith. Yes, without that contribution the carpentry would not be possible. But that does not mean that it isn't carpentry - precisely because without it carpentry would not be possible!

    Same for science. There is no contradiction between the observation that philosophers of science came up with the concept of falsifiability (after scientists had been using it unthinkingly for ages, one could add) and the observation that it is a scientific tool or concept.

    Fundamentally, Duhem noted that in actual scientific practice there is a complex relationship between theory and observation or experiment [...] experiment doesn’t strictly speaking test the theory itself, but rather a complex web of notions that comprise the focal theory (say, the Standard Model), a number of corollary theories and assumptions needed to build it, as well as assumptions about the correct functionality of the measurement instrument, the way the data are analyzed, and so on. If there is a mismatch, Duhem argued, scientists don’t immediately throw away the theory. Indeed, the first thing they are likely to do is to check the calculations and the instrumentation, moving then to the auxiliary assumptions, and only after repeated failures under different conditions finally abandon the theory (if they had strong reasons to take the theory seriously to begin with). [...] But if we are to speak precisely, what we are testing every time is our entire web of knowledge. If something goes wrong, the problem could in principle reside anywhere in the web. It is then up to clever and creative scientists to focus on the most likely culprits, eliminate the ones they can, and eventually reach a consensus as a community regarding the soundness of the theory being “tested.”

    That is all very nice but it does not change anything about the main point. You basically argue that instead of falsifying a hypothesis, we first check if our instruments are wrong and then... falsify a hypothesis. I would have assumed the second step here was so self-evident that Popper would not need to mention it.

    That’s why science is just as much an art as a logical pursuit.

    One of those sentences where your mileage can clearly vary. I assume you mean that it needs intuition and talent. When I read it, it sounds like "we make things up and are happy when they are pleasant." Maybe I have a different understanding of the word art.

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  14. Gadfly,

    > What if, for all practical purposes, a theory that theoretically has empirical outputs can never be tested in a state to find those? <

    Then it would be a potentially testable theory which may never actually get the pleasure of being tested. Which would show one type of human epistemic limitation.

    > as for replacing falsification, if you were to take your own shot at the issue, Massimo, what would you write up? <

    A textbook in philosophy of science, showing how falsification has been replaced by a combination of historicism and pluralism. But there are several such books already out, I highly recommend Alan Chalmers’ What Is This Thing Called Science?

    mufi,

    > I wonder how common it is for scientists to cross that demarcation line. Perhaps this is another way to frame your objections to “scientism" <

    Interesting question, though of course we have to remember — as Baggott makes very clear — that science comes with a lot of metaphysics and epistemology embedded in, and usually un-analyzed by scientists. For instance the assumption of uniformity of the laws of nature, the reliability of induction, etc.

    > I suppose that I can make peace with your use of "metaphysics" as a non-dirty word <

    Much obliged… ;-)

    Cian,

    > Sean is, I think, right to distance himself from the Popperian notion of falsifiability <

    Indeed, but my point is that such distancing, coming in the second decade of the 21st century, is a bit of a straw man, since nobody in philosophy has been a strict falsificationist for almost a century.

    > that such things are mathematical consequences of useful theories provides some minor confirmation to them. If this is what Sean claims, then his reasoning is not circular in Baggott warns. <

    Well, to be fair, Baggott is taking on other cosmologists (like Susskind), not Sean. At any rate, I actually don’t see any of what you mention as a confirmation of the multiverse, even indirectly. Yes, IF the multiverse is true THEN certain nasty problems, like fine tuning, go away. But I’m not willing to accept the multiverse just because it neatly solves another problem. It has to stand on its own.

    miller,

    > My impression is that many people (not necessarily scientists, just the general public) indeed accept falsificationism, and use it to criticize string theory. <

    Yes, I’m aware that a lot of people in the skeptic community love to use falsificationism as a trump card. But this only supports my contention that people in the skeptic community need to study some philosophy of science 101…

    > the accusation of "circular reasoning" applies to knowledge with a foundationalist structure, and not necessarily knowledge with a web structure <

    Agreed, and I actually made that point recently on the blog.

    Mark,

    > Sean would point out that any discussion of physics with you would be him teaching you, not a debate <

    Not sure why you felt that comment was necessary, since I wasn’t challenging Sean on the physics, for precisely the reason you hint at.

    > That is a limitation of our technology, not an indictment of the contemplations. <

    Well, but if those technological limitations are permanent, or likely so, than this does become a serious limitation for the science one wants to do.

    > the contemplations have produced entire new fields in pure math. <

    Indeed, but unless and until they will make empirical contact that’s just not enough to consider the theories in question to be scientific.

    > Even "conscious being" is poorly formed. Come on, Massimo. <

    I think I have a pretty good idea of what “conscious being” means. You don’t?

    > I'm sure Sean can talk about many different lines of evidence for why a multiverse stands on its own or not. <

    According to Smolin, Woit and Baggott he actually can’t. They are all physicists.

    > but I still like you more than Jerry Coyne! <

    Well, that’s a relief! ;-)

    > more comments coming later today... <

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    1. Hi Massimo,

      I just wanted to jump in on this since I made the same point.

      >> Even "conscious being" is poorly formed. Come on, Massimo. <

      I think I have a pretty good idea of what “conscious being” means. You don’t?<

      You may think you have a pretty good idea of what it means, but that doesn't mean you can define it precisely as required by Carroll. Plenty of people think they have a pretty good idea of right and wrong, or of what "knowledge" means, but that does not mean that these are not problematic concepts with many different possible interpretations. Consciousness is the same, I think.

      Any definition of consciousness either ends up matching some appropriate computer software or appealing to another level of equally fuzzy problematic concepts like "awareness", "qualia", etc.

      It is far from a trivial problem to capture precisely what it is that fundamentally distinguishes us from artificial intelligences, so much so that many (myself included) think that no such fundamental distinction exists.

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    2. Massimo: ...science comes with a lot of metaphysics and epistemology embedded in, and usually un-analyzed by scientists. For instance the assumption of uniformity of the laws of nature, the reliability of induction, etc.

      Yes, I'm aware of those assumptions, but I like to think that scientists treat them pragmatically - that is, they see that those assumptions work well enough (e.g. in terms of predicting correlations between phenomena) to qualify as a means to stable knowledge, whatever the "ultimate" status of that knowledge may be.

      And I say that "I like to think" because I'm also aware of the possibility (if not probability) that I'm making a naive and over-generalized assumption here about how scientists think and behave.

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  15. DM,

    > You're nitpicking! It's a concept from philosophy of science. It pertains to science. It is scientific in that sense. <

    I disagree, it ain’t nitpicking. Obviously it is pertinent to science, but it is a philosophical concept, and you may have noticed that I’m fed up with people dismissing philosophy (not Sean’s case) while at the same time arrogating philosophical concepts to their own discipline (both Sean and you-know-who-the-initials-are-SM…).

    > I think the statement about God is very much an example of what is not 'definite' in the sense Sean Carroll means <

    I disagree, it’s a perfectly intelligible statement, despite your dig at consciousness. And the fact that it is not mathematically expressed makes no difference, unless you also want to exclude from science all sorts of disciplines that don’t rely as heavily as fundamental physics on mathematical theorizing.

    > Anthropic arguments and anthropic thought surely existed before the concept was codified, published and given a name. That does not mean that these were not applications of the anthropic principle. <

    It does because there is no evidence whatsoever that Hoyle was thinking along those lines. But people nowadays like to attribute his prediction to applications of the anthropic principle — in the specific sense that was articulated in the ‘60s. Clearly, a case of retroactively forcing history to fit one’s preferences.

    > I see no circularity there at all. I have this elegant theory of gravity that would very nicely unify the orbits of the planets and the behaviour of objects falling to earth, so I think my theory of gravity is on the mark <

    You accept your theory of gravity because you have empirical evidence that supports it, which is lacking in the case of the multiverse, by Sean’s own admission.

    > I don't see why not. It may not be tremendously strong evidence, but it is evidence to a point. <

    I don’t see why it is, at all.

    > It at least has the potential of resulting in verifiable predictions. <

    The keyword there being “potential.” How long are we going to wait? Is the potential going to turn actual in the foreseeable future, or is it potential in the sense that the theory is verifiable “in principle” but we are never going to get there because of human epistemic or technological limitations?

    > "Science is supposed to make contact with the empirical world, at some point", but who is to say when that point is? <

    So we just wait around forever and in the meantime write books for the public that trumpet the new “discoveries” of fundamental physics, like Brian Greene does?

    > so though it may be drifting away from science in the strictest Popperian sense of the word, who actually cares? <

    You and I do, otherwise we wouldn’t be having this discussion. C’mon, don’t use the “who cares?” argument, it’s not argument, at all.

    > It's still valuable, worthwhile work that needs to be done <

    Why, exactly?

    > I propose not "pseudoscience", not "metaphysics", but "theoretical physics” <

    Nope, because theoretical physics is a science. I propose mathematics instead.

    Kel,

    > "(if Jerry Coyne wants to debate evolutionary biology with me, that’s another matter…)"
    That would make for an excellent episode of Rationally Speaking. <

    Yeah, but I sincerely doubt Jerry would accept.

    Philip,

    > “Theory”, in physics, means: a set of equations that can be used to make predictions for physical processes in a real or imaginary world.

    I'm not sure what is meant by an imaginary world, but it would seem to give theoretical physicists some room to roam. <

    Or it’s simply an example of a theoretical physicist indulging in bad philosophy.

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    1. Hi Massimo,

      >I disagree, it ain’t nitpicking.<
      It's not nit-picking to point out that falsifiability is a philosophical concept if somebody is presenting it as a scientific concept. It is nit-picking to describe Carroll's choice as "odd", especially since he made clear that it was a concept from the philosophy of science. I think this may have been a case of my misunderstanding your intended tone, however.

      >I disagree, it’s a perfectly intelligible statement, despite your dig at consciousness.<

      Even if I allow that consciousness is a "definite" concept (which I don't), then you still have to explain what it means for a conscious mind to exist outside of time and space. A mind is either a property of a biological brain (your view) or a computational process (my view). How either could exist outside of time and space is beyond me.

      The very fact that these terms are ambiguous is enough to distinguish your statement about God from String Theory, which as a mathematical framework is anything but ambiguous.

      I think Carroll is right. The more closely statements about the real world hew to the mathematical, the more "scientific" they become. In this view, the physical sciences are more "scientific" than the social sciences, although I'm sure many sociologists would disagree. However, it is not required that statements be mathematical, only that they be clear and unambiguous.

      >It does because there is no evidence whatsoever that Hoyle was thinking along those lines. <

      OK, that argument I could buy, but the argument as presented was that it was prima facie implausible that anybody could reason according to the Antropic Principle before 1960.

      >You accept your theory of gravity because you have empirical evidence that supports it, which is lacking in the case of the multiverse<

      What I said about gravity was only to demonstrate that the form of the argument was not sufficient to demonstrate circularity. While not for a second trying to make the case that there is anything like the same evidence for a multiverse as there is for gravity, I still don't see the circularity in the multiverse argument from fine tuning.

      And I still think that fine-tuning constitutes evidence.

      As I see it, there are four answers to fine tuning.
      1) The universe is not fine-tuned
      2) Godidit
      3) The anthropic principle
      4) The universe is necessarily fine tuned because the constants etc could be no other way.

      We both discount (2). I think (4) doesn't really answer the question but only puts it back one level (a bit like Godidit).

      I think you prefer (1). That's OK, but if you could be persuaded that (1) was not a viable option, would you not be inclined to suspect that a multiverse probably exists?

      >The keyword there being “potential.”<

      Indeed. A key thing which distinguishes it from metaphysics. So even if you convince me it isn't science, you're a long way from convincing me it's metaphysics.

      >> It's still valuable, worthwhile work that needs to be done <

      Why, exactly?<
      Even if it's all wrong, it's exploring new kinds of reasoning and developing problem solving and adding to human knowledge in the same way as pure math does. And it just might turn out not to be wrong.

      >Nope, because theoretical physics is a science. I propose mathematics instead.<

      You seem to be arguing that some theoretical physics is not science. Whether string theory is science or not, I don't much care. It is or it isn't, depending on how you define science. I do think it bears such a strong resemblance to other fields of theoretical physics that it would be perverse not to count it as such.

      It may be that it is mathematics but that is too broad because it is a very specific kind of mathematics devoted to developing hypothetical mathematical theories descriptive of the physical world. Hence, theoretical physics.

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    2. DM,

      I think Carroll is right. The more closely statements about the real world hew to the mathematical, the more "scientific" they become.

      By "real world" do you mean the world we observe, or would you expand your meaning to include worlds we cannot observe but might exist "somewhere" according to some carefully specified theory? If the latter, then what is to stop us in principle from considering worlds of two spatial dimensions plus one time dimension as real?

      In fact, considerable simplification of a theoretical framework can occur if one reduces the number of spatial dimensions to two, even making a theory mathematically exact in some cases where it would be intractable in three spatial dimensions. Would you consider it correct to call a 2+1 dimensional theory that is mathematically precise and empirically predictive (i.e., has observational consequences for "observers" in such a 2+1 dimensional universe, if it existed) a scientific theory?

      As I see it, there are four answers to fine tuning.
      1) The universe is not fine-tuned
      2) Godidit
      3) The anthropic principle
      4) The universe is necessarily fine tuned because the constants etc could be no other way.


      You have omitted at least a couple of other, important possibilities that a nontrivial number of physicists believe:

      5. There is actually no fine tuning problem because somewhere in our current fundamental theories there lurks one or more (probably more) incorrect fundamental assumptions (implicit or explicit), the consequences of which lead to a false problem. This possibility isn't as controversial as it might seem to some, given that we already know that getting quantum mechanics and general relativity to smoothly and consistently work together ("quantum gravity") will almost certainly require some current assumption(s) to change, although this example has nothing to do with fine tuning per se.

      6. Our fundamental theories are mostly OK, but Nature has more surprises waiting for us that, once discovered, we can incorporate into our current theoretical framework --- these will fortuitously eliminate fine tunings, or at least substantially reduce their magnitude. Supersymmetry was largely invented for that purpose.

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    3. I guess I should point out that in my earlier reply, your option #1 (which seems pretty general) subsumes my #5 and #6. I listed them because they are viable, concrete possibilities, yet very different in origin.

      Your distinction between #3 and #4 isn't real clear to me; it seems like they have at least some overlap.

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    4. Hi Marty,

      >By "real world" do you mean the world we observe<

      In this context I do indeed mean the world we observe.

      I think your alternatives #5 and #6 fit either under my #1 or #4, depending on what it is that these new theories find. If they find that the universe could be very different but still support life, they fit under #1. If they find that the universe could have been no other way, they fit under #4.

      #3 and #4 are completely different. #3 explains it by arguing that there are a multitude of universes, each very different, only some of which support life. #4 argues that there is only one logically possible universe, and so we should not be surprised that this universe is finely tuned for life because it could have been no other way.

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    5. Massimo,

      >> “Theory”, in physics, means: a set of equations that can be used to make predictions for physical processes in a real or imaginary world.

      I'm not sure what is meant by an imaginary world, but it would seem to give theoretical physicists some room to roam. <<

      >Or it’s simply an example of a theoretical physicist indulging in bad philosophy. <

      Actually, more like amateur anthropology. Philosophers don't have unique dominion over the meaning of words, after all. Strassler is merely characterizing the fact that theoretical physicists use the word "theory" to mean something different from the philosophy of science concept of the same name. As I point out here (http://4gravitonsandagradstudent.wordpress.com/a-theorists-theory/) there really are a huge number of examples that support Matt's point.

      One thing I think is getting missed about string theory is that it's solving a different sort of problem than quantum mechanics, and thus probably should be treated differently from a philosophical perspective. Quantum mechanics arose in order to explain a series of anomalous experiments, so it makes sense to test it on the real world. By contrast, string theory's "purpose" (not historically, but conceptually, especially when put alongside with Loop Quantum Gravity et al) is to provide a renormalizable quantum theory of gravity. The "anomalous observation" that general relativity is not renormalizable is an observation about the mathematics, not about the world. While claims about quantum gravity might be testable with some sort of absurdly high energy post-scarcity collider, for the moment such claims are intended to fix a problem in the theoretical framework, not a problem in experiment. It seems more appropriate to expect such claims to test themselves against the properties of such frameworks, rather than against the properties of the world.

      This idea of theories (in the philosophy of science sense) pertaining to theories (in the theoretical physics sense) seems like something that philosophers of science ought to have looked into. Do you know if anything has been written on the subject? It seems like it ought to have come up before in respect to experimental mathematics at least.

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    6. Hi DM,

      >>By "real world" do you mean the world we observe<<

      >In this context I do indeed mean the world we observe.<.

      Then, as I'm sure you agree, no matter how carefully and mathematically precise a theory is, we still have the problem of determining whether the theory correctly describes the world we observe. This issue is orthogonal to logical completeness.

      Mathematical/logical consistency and agreement with currently known facts (and prejudices!) is obviously not sufficient --- without guidance from Nature it is very easy to go astray, as a long line of historical evidence shows If you do away with falsifiability, how do you decide the relative correctness of two similarly precise theories that rely on dissimilar premises and offer very different explanations for the same known phenomena? That's why Carroll gets so much flak: His position about mathematical/logical rigor that you summarized is not controversial among scientists, rather, it his desire to downplay the need for experimental and observational feedback from Nature.

      >I think your alternatives #5 and #6 fit either under my #1 or #4, depending on what it is that these new theories find.<

      I don't think my #5 or #6 really fits with your #4. In both scenarios there is no fine tuning at all. But maybe I'm misunderstanding what you mean in #4. Maybe you're saying the constants of Nature (among other things, like the number and integer-valuedness of spatial dimensions, the known internal symmetries of elementary particles, ...) are uniquely determined; i.e., if we had the correct theory we'd see they could be no other way. But if that's what you mean, it seems to me there is no fine tuning.

      As I hinted, I thought your #1 was very general compared to #2 - #4. At a similar level of generality, #2-4 could be reduced to a single alternative, leaving you with (a) Nature is not fine tuned (#1), or (b) Nature is fine tuned (#2-4). That reduction doesn't seem very interesting, so it seems worthwhile to elaborate #1 a bit...

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  16. Mark,

    > I have the sense that much of the debate and discussion is motivated by a desire to score points against a high prestige discipline on the part of those who may be associated with disciplines (or subdisciplines) with a perceived lower status <

    Whatever people’s motivations (no human being has entirely “pure” motivations, whatever that may mean), the issues being raised are still seriously, and it behooves the physics community to address it — particularly because of the costs associated with this type of research, costs that are paid by the rest of us.

    > Doesn't such a stance – eminently reasonable as it is – raise some awkward questions about the efficacy of the philosophy of science and indeed metaphysics as independent disciplines, distinct from the sciences in question? <

    Not sure why that would be. The job of philosophy of science, as I see it, is to make sense of science and occasionally to criticize its methods or findings, especially but not only when they have social consequences.

    Alex,

    > falsifiability of all things? Yes, that one is a scientific concept; if it isn't, then there are no scientific concepts. <

    I guess I would have to ask you how you came up with that conclusion. The concept was articulated by a philosopher (not a scientist) within the context of two philosophical (not scientific) problems: demarcation and induction. How, then, is falsificationism a scientific concept, all of a sudden?

    > This is your usual argument: the moment a scientist uses something like Occam's Razor for example, you conclude that they have cheated and are really doing philosophy. <

    You misunderstand me my friend. Occam’s razor most definitely is a philosophical concept (again, articulated by a philosopher, within the context of a philosophical discussion) which is useful to science. How about the scientists acknowledge that they get something useful out of philosophy, for a change? Then I would be perfectly happy with their usage.

    > That is all very nice but it does not change anything about the main point. You basically argue that instead of falsifying a hypothesis, we first check if our instruments are wrong and then... falsify a hypothesis. <

    That changes things greatly, actually. You may want to take a look at the SEP entries under Popper and Duhem.

    > One of those sentences where your mileage can clearly vary. I assume you mean that it needs intuition and talent. When I read it, it sounds like "we make things up and are happy when they are pleasant.” <

    You assumed correctly and read uncharitably…

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    1. > I guess I would have to ask you how you came up with that conclusion.

      I explained my reasoning in the next few lines; you merely chose not to address it.

      Again, if you call all conceptual thinking not science and reduce science to making one lab experiment after the other then there simply are no scientific concepts, and the Edge question would be meaningless.

      What would you call a scientific concept? Evolution perhaps? But well, that is an overarching theory, so it also goes beyond one experiment at a time, and didn't you once write an article arguing that evolution is not so much an empirical observation as an unavoidable, logical and necessary consequence of replicators with heritable characteristics being faced with limited resources?

      Again, if using a tool provided by some other profession* means that you are not doing your own profession any more then there exist, for example, no population geneticists on this planet because it is really math. That view is self-evidently absurd - well, just like the view that a scientist is not doing science when invoking falsification or parsimony.

      > You may want to take a look at the SEP entries under Popper and Duhem.

      If Popper was really unaware that an experiment can fail for a variety of technical reasons or mistaken assumptions then he was an idiot. Because one should assume that nobody who is able to eat with a fork without putting their eye out would believe something like that, I assumed that these qualifications were implicit in his faslificationism - too obvious to need mentioning.

      *) And again the third, one could have a productive discussion about whether the following story describes history as it happened:

      A philosopher thinks hard for a long time, comes up with the idea of falsification, walks over to a scientist and explains it. The scientist replies, "what a great idea! Amazing that nobody thought about doing that the last few thousand years, for example when farmers tried out different cropping regimes or tradesmen tried out different ways of constructing things. Would have saved them a lot of bother if they had just realized that they should discontinue using approaches that don't work. But of course, how could they have known? After all, it needs a fully trained and qualified philosopher like you to tell us hoi polloi how to think; no surprise after all. Anyway, let's tell all other scientists and from now on do science the way you suggest."

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  17. It seems somewhat ironic to me that an advocate for a 'theory of everything' would justify removing the idea of 'falsification' based on the fact that experimental results are always to a degree dependent on web of assumptions contained in the theory behind the experiment. This same argument might be made by an extreme relativist who says scientific claims are social conventions.

    Now don't get me wrong, I think all experimentalists need to be constrained by this limitation when doing science, just as we as subjective observers would do well to recognize our fundamental unconscious bias's and limitations in forming beliefs about the world. The lack of an absolute foundation with regard to observation however does not justify placing ultimate faith in pure theory (or math). I think just as the experimentalist needs to remember the dependence of experiment on theory, the theorist needs to also be constrained be experiment if we are to call the theory science. Falsification I think needs not to be retired nor idealized, but placed into it's useful context whereby the mutual constraint of theory and experiment support each other promote progress in science.

    I like Gieres' view that a plurality of perspectives are necessary, and that doesn't diminish the utility of seeking to unify perspectives, yet each unification is also a perspective.

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  18. Little off topic here, but genuinely curious about the response. And given the level of angst against a perceived disregard for the value of philosophy that keeps popping up in your blog, seems like a reasonable (but probably incendiary) topic.

    My sense is that just most if not all philosophers at respected institutions would say that the study of physics, biology, or chemistry is some combination of useful (technologically and because we get value from understanding), meaningful, relating to reality, and worthy of public money.

    On the other hand we have a growing number of physicist, biologists, and chemists at high level academic positions questioning whether philosophy as a distinct discipline - or at least a lot of its current manifestation - has much value to it at all.

    I assume your, and others’, argument would be that those physicists, biologists, and chemists just don’t understand philosophy or the value of it because - and this is where my question comes in - because they aren’t smart enough? Because they think they understand philosophy, but really don’t? A “yes” to both of these questions has been my sense of what the most philosopher’s retort is when confronted with this type of question.

    And I can’t shake this feeling of…I don’t know…Irony. That the people who study quantum mechanics, for instance - some of the most intelligent people on the planet who can problem solve in the most abstract and non-intuitive ways to figure out how the universe fundamentally works - are perceived as not intelligent enough to understand “high level” philosophy. Doesn’t this seem strange?

    Of course there’s a few of assumptions I’ve made that could be wrong. For one, maybe there are actually just as many philosophers who argue against the meaningfulness of physics, biology, and chemistry as there are scientists who argue against the value of philosophy as a distinct discipline. Two, maybe philosophers argue that the scientists who reject philosophy don’t understand what they’re rejecting, but it has nothing to do with those scientists’ intelligence. Maybe it's all just bias? Three, maybe I’m much too charitable in assuming that scientists like quantum physicists represent the most, or at least more, intelligent people on the planet.

    Again, just trying to get a sense for what it means to philosophers that more and more highly regarded and respected scientists are beginning to question the value of philosophy as a distinct discipline, but almost never does it seem that the reverse is true.

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  19. I have a very mundane view: It seems that philosophers can help in clarifying the language of scientists (e.g., theoretical physicists). When scientists talk about a theory, "What is a theory?" comes to mind. Vague definitions are unsatisfying. So when they say "A theory is a set of equations plus ..." one has to question first "What is their language of equations?" (I mean "language" in the sense of a formal definition as practiced in mathematical logic and programming language theory.) And then there's the ... .

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  20. Hi,

    You are implying that computational processes cannot occur outside of space-time. On what are you basing that?

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    1. Hi Robin,

      I'm guessing this was targeted at me?

      I think the definition of the word "process" rather implies time. Don't you?

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  22. You are way too easy on Carroll. String theory and the multiverse are pseudoscientific because they do not make testable predictions. They are not falsifiable. You say that they are "speculations somewhat grounded in well established physics" but they are metaphysical speculations, and the well established physics gives no reason to believe the speculations. The Popper notion of falsifiability works fine for dispensing with these ideas as unscientific.

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    1. Hi Roger,

      >String theory and the multiverse are pseudoscientific because they do not make testable predictions.<

      I disagree with this completely. You may have a point that they should not be considered to be traditional science, but to call them pseudoscience is unwarranted derogatory hyperbole in my view.

      Pseudoscience describes homeopathy, alchemy, cold fusion and perpetual motion hoaxery. Pseudoscience is fraudulent, ignores evidence and seeks to deceive. This does not describe what string theorists are doing. Their approach may prove to be incorrect or fruitless, but they are at least being intellectually honest about it.

      If your criteria for identifying pseudoscience cannot distinguish between quacks and theoretical physicists, then you need new criteria.

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  23. Yes, I am not sure why it went there.

    No, I don't think the word "process" implies time, it only implies process.

    It certainly doesn't imply space-time.

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    1. Hi Robin,

      Saying that "process" only implies "process" kind of reduces it to meaninglessness, wouldn't you say?

      Of course "process" implies time. No process can take place outside of time, simply going by the definition of the word. Take a look at these definitions from Webster's and tell me which one leads you to believe that a computational process could take place outside of time.

      =================
      a : progress, advance [in the process of time]
      b : something going on : proceeding
      2
      a (1) : a natural phenomenon marked by gradual changes that lead toward a particular result [the process of growth] (2) : a continuing natural or biological activity or function [such life processes as breathing]
      b : a series of actions or operations conducing to an end; especially : a continuous operation or treatment especially in manufacture
      3
      a : the whole course of proceedings in a legal action
      b : the summons, mandate, or writ used by a court to compel the appearance of the defendant in a legal action or compliance with its orders
      4
      : a prominent or projecting part of an organism or organic structure [a bone process] [a nerve cell process]
      5
      : 6conk [[which is a kind of hairstyle, apparently - DM]]
      ======================

      It may not imply space-time, but my point was that it implies time. If God exists outside of time and of space, then God exists outside of time and God cannot be a process.

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    2. HI, DM. Let me remind you of the point I was responding to "How either could exist outside of time and space is beyond me.",

      You see? Time and space. Now you have backtracked and are talking about some kind of "time" that would make sense apart from the concept of space-time.

      So I am not sure what your new claim is.

      So can we agree that it is not impossible that there is a process that is not part of the space-time universe we observe???

      Or are you saying that the process of space-time is the only kind of process possible

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    4. Disagreeable Me wrote: "
      Saying that "process" only implies "process" kind of reduces it to meaninglessness, wouldn't you say?"

      No, because I said "implies" and not "means". A process does not imply anything beyond its own definition.

      As I pointed out before if you are disaggregating the notion of time from space then you are using it in a non-standard form.

      But even so there are differences, for example time implies the concept of "duration" whereas process does not. Take a computation that is a set of discrete steps. The duration of a step is meaningless there, as is the duration between steps.

      Although the concept of time is often used in algorithmic information theory it merely means number of discrete steps and is expressed as a whole number, rather than duration which is expressed as a real number.

      So really there is nothing about the concept of "process" which implies "time" at all although the reverse may be true.

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    5. Hi Robin,

      I assure you I am not backtracking or making any new claim. It is more likely that you interpreted what I said initially incorrectly, although the fault may be mine for expressing myself poorly,

      Why a computational process cannot exist outside of time and space:

      I take "exist outside of time and space" to mean not taking place in time and not taking place in space. To establish my claim, I only have to show that either time or space is necessary for computation, not space-time specifically.

      I'm going to concentrate on time. Time as a concept does make sense, in my view, even without reference to space. All that is required is a structure where some events take place after others, with the past influencing the future but not the reverse. In other words, directed causality.

      >So can we agree that it is not impossible that there is a process that is not part of the space-time universe we observe???<

      I believe in the multiverse, so of course believe that processes can exist outside of the space-time we observe. My claim is that no process can be timeless, existing entirely outside of and independently of some kind of time, although the timeline of that process may have no relationship to time within our universe.

      >Or are you saying that the process of space-time is the only kind of process possible<

      I'm not sure I would describe space-time itself as a process.

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    6. Hi Robin,

      >A process does not imply anything beyond its own definition.<

      Then you simply don't understand what I mean by implies. The meaning of the word process depends on the concept of time even though it is not identical to the concept of time. The word "process" implies the existence of time in the same way that "disagreement" implies the existence of at least two different viewpoints.

      >duration which is expressed as a real number.<

      Not necessarily. There may be a natural discrete unit of time, the Planck time.

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    7. Hi DM,

      Yes, I do understand what "implies" means - however you may mean something else by it.

      It appears we are talking at cross purposes. When you said "space and time" I assumed you were referring to the space time of physics or time in the ordinary sense.

      I have never seen time expressed in natural numbers anywhere but I suppose you are free to use the term to cover any kind of directed sequence.

      If all you mean "time" is "process", then yes - of course it is trivially true that you cannot have a process without a process.

      Using your definition of time it is also true that nothing at all can happen outside of space and time. 'Cept maybe randomness.

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    8. Hi Robin,

      I wouldn't use time to describe any kind of directed sequence. It would have to have some kind of possibility of supporting causality.

      I do not mean that "time" is "process", I mean that time is necessary to support processes. Time is the medium in which processes take place. This is like the difference between "space" and "shape".

      I would agree that nothing at all can happen outside of time, the same way that nothing can have a shape or a location without space. But plenty of stuff can exist outside of time, for instance mathematical objects.

      For some Christians, God is such an object. I maintain that He cannot be. If God exists outside of our universe, that's OK, but he must then exist in some other kind of reality which has something very much like our concept of time.

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    10. Again, we are simply talking at cross purposes. You seemed to mean by "time" what I mean by "process". So we can never agree unless we agree our terms.

      Now I understand that by "time" you mean "any environment in which there can occur, at least locally, causally ordered sequences".

      Yes?

      This would be like our concept of time just as long as we adopt a concept of time as "any environment in which there can occur, at least locally, causally ordered sequences"

      I can only say that this is not really my concept of time.

      So can we agree that it is trivially true that processes cannot occur in any environment in which processes cannot occur? And perhaps recognise that we might attach different concepts to words like "time"

      Personally I don't think that the mind can be a computation anyway, for various reasons.

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    11. Hi Robin,

      Normally I'd be happy to accept different definitions of terms and move on, but I really do object to the implication that there's something funny with my definition of "time".

      I wouldn't precisely describe time as an environment but of a property of an environment. An environment that allows causally ordered sequences has time, but that environment might also have, for instance, space.

      When you say this "would be like our concept of time" you are, by that word "our", separating me from the rest of humanity and implying that I have my own weird idiosyncratic interpretation of time that bears little relation to "real" time. I don't see it that way. I don't think my attempt to define time is much different from the usual intuition. At least I don't intend it to be.

      "it is trivially true that processes cannot occur in any environment in which processes occur"

      I think you meant to balance your "nots" here? Processes can occur in any environment in which processes can occur, or processes cannot occur in any environment in which processes cannot occur. Indeed! And it is indeed trivial, and tautological, and obvious, which is why it seemed strange to me that you think that processes can occur outside time, seeing as in my view processes require time *by definition*.

      >And perhaps recognise that we might attach different concepts to words like "time"<

      Sure. If you specifically mean time in this universe, then I don't have any issue with the concept that God exists outside of time, as long as he has something analogous to time to work with instead.

      But doesn't this rather prove my point that there is nothing particularly "definite" about Massimo's original statement? We and others have got quite a bit of mileage out of trying to interpret what it might mean.

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    12. I see you removed your previous post and fixed a mistake, therefore making my commenting on that mistake unnecessary.

      Oh, for an edit button!

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    13. No I don't mean specifically time in this universe. I have already pointed out that my definition of time differs from yours by the concept of "duration". A causally ordered sequence need not involve duration at all in the sense that we mean "duration" about our time.

      If there is no fact of the matter about "duration of step" or "duration between steps" then a causally ordered sequence might have no duration at all.

      And if that sequence of steps included an algorithm equivalent to a conscious mind then that mind might experience a duration which has nothing whatsoever to do with any concrete entity.

      I don't say that your concept of time is idiosyncratic just that I have a different one. But it seems to me that the common conception of time includes the concept of duration - I could be wrong about that.

      You are right about Massimo's original statement not being definite and that is because modern cosmologists have not in any way increased our understanding of what it might mean to be "out of time" beyond the understanding of St Augustine or even when Plato suggested that something could be out of time.

      What we do have is that the concept, that time began to exist and that something caused it to begin to exist, is being taken seriously by scientists which must mean that either something exists out of time or that we have to expand our scientific notion of time.

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    14. If mind is a computation then I don't think that a God as envisaged by Christian religions can exist at all but it forces us to take as plausible the existence of any number of demiurges.

      In "A Universe from Nothing" Krauss responds to the question of why our laws of nature are such that they can give rise to a universe like ours, that if the laws are random then anything that is not explicitly ruled out must happen.

      A computation is not explicitly ruled out and a computer is a vastly simpler entity than a universe like ours and so, taking Krauss at his word, we must assume that independent computational processes vastly outnumber universes such as ours.

      If a mind is just a particular type of computational process then we can plausibly assume that minds existing outside of universes such as ours vastly outnumber such universes.

      If computationalism is true then such a mind would only have to design and think though a particular algorithm in order to create a Universe like ours.

      So given Krauss's premises and adding computationalism we would have to say that it may well be more probable that our universe was designed than not.

      Of course I am being a little tongue in cheek here.

      But if we ditch verifiability and falsifiability then there is not much (if anything) to choose between the above and standard multiverse conjectures.

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    15. Hi Robin,

      Sorry, I didn't recognise that "duration" constituted a difference. In any series of discrete steps, duration has a clear analogue in terms of number of steps. As I have mentioned, time in this universe may work in this way, as a sequence of discrete Planck time steps. We don't really know, but we do know that it seems to be nonsense to talk of durations shorter than this.

      Whether it turns out that our time really is discrete or really is continuous, I don't think we would throw out the concept of time altogether one way or another. If we are willing to accept that our universe may contain discrete time, then I see no reason to see my concept of time as that different to yours.

      >If there is no fact of the matter about "duration of step" or "duration between steps" then a causally ordered sequence might have no duration at all.<

      This confuses things somewhat. In any such "environment", a "step" would be the ultimate unit of time. Each step would have a duration of one step, by definition. If you made each step take twice as long then nothing would change, as no observer could possibly notice the difference.

      You may take Krauss's argument tongue in cheek, but I take it literally and I believe it, and it leads me to the opposite conclusion to yours.

      I take issue with the idea that a computer is simpler than a universe. In a way it must be, because it is contained in the universe, but in another it is much more complicated. The universe can essentially be defined by the laws of physics, which though currently not completely understood, are almost certainly much simpler than a computer. Simplicity can lead to complexity, and there are numerous examples of this (e.g. evolution, cellular automata).

      As it happens, I do believe that all possible mathematical structures do exist, however I think the number of demiurges that exist independently of any hosting universe is going to be absolutely dwarfed by comparison to relatively simple universes like ours which hosts conscious entities.

      So, I do believe it is possible in principle that this universe was designed by a tremendously complex Godlike mathematical being, but it is vastly more probable that the explanation is the simple laws of physics themselves.

      But even if the universe were designed by this math-God, as long as the laws of physics do describe accurately how the universe functions (i.e. no intervention from God), the universe would exist independently of that God anyway, so that God is unnecessary and irrelevant.

      I've thought about this a lot :)

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    16. Here is your mistake. You think that I am talking about lengths of time shorter than a unit of Planck time. That is because you cannot rid yourself of this notion of time.

      I am not. I am talking about there being no fact of the matter about a duration of a step or duration between steps. You could not not make any step twice as long because the very concept of duration is not required.

      Number of steps and duration are simply not equivalent terms. A unit of Planck time has a duration. We use real numbers to model duration.

      If you want to ignore the vast differences in these concepts then fine. Don't ask me to agree with it.

      You keep wanting to force this particular card, but you keep it.

      I will define something with only the concepts required for the definition and not more.

      Now I did not say that Krauss's argument was tongue in cheek, merely mine. I realise that Krauss was absolutely serious.

      You are simply incorrect about computers being more complex than the Universe. You appear to think that the existence of computers in the Universe implies they are more complex than the Universe. It does not follow.

      I can define the logic of the simplest universal computer in 32 bits. Try defining the Universe in 32 bits.

      So there is no question at all that a universal computer is vastly, vastly simpler than our universe and unquestionably the Universes like ours would be vastly, vastly outnumbered by computational processes that did not require universes like ours to support them.

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    17. Now of course improbability would not be an issue with a God as defined by the Abrahamic religions since it is defined as a necessarily existing entity and complexity implies improbability only in contingent beings.

      To Krauss's argument he says "no mechanism and no entity is required to fix the laws of nature to be what they are".

      No mechanism - except a stochastic process which assays the entire search space of "anything that is not forbidden".

      He arbitrarily stops the regress there. The question is - why a stochastic process which assays the entire search space of "anything that is not forbidden" rather than something else. After all there are infinitely many logically possible stochastic processes which would assay only a small uninteresting search space over and over again even if infinite in scope and duration.

      So you have got to ask how improbable that stochastic process would be. Maybe it is necessarily existing and so the improbability is not an issue.

      But that does seem to indicate that at least one thing needs to necessarily exist.

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    18. Incidentally, when the above appears, I misread your reasoning about the complexity of computers. All the same a universal computer is, as I sais, vastly, vastly simpler than a universe such as ours.

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    19. If you don’t believe me about the simplicity of computers consider your examples of complexity from simplicity - cellular automata and evolution.

      You probably have Conway’s Game of Life in mind for a cellular automaton. But Game of Life is in itself a universal computer.

      It can do any computation that any other possible computer can. And it is not even the simplest such computer.

      So your starting simplicity is already as complex as the most powerful computer possible.

      For evolution, even for a starting point, you need a self replicator. In The Grand Design Stephen Hawking says that it has been estimated that the simplest self replicator on Game of Life would be approximately 10 trillion squares (based on work by Von Neumann).

      So the simplest source of complexity we know if really is a computer. It is highly doubtful that there can be a simpler source.

      So the vast majority of Krauss’s search would turn up no complexity at all. Of the things that produce complexity, the vast majority would be computers.

      And the mechanism he describes would likely itself be more complex than the simplest universal computer.

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    20. Hi Robin,

      >You think that I am talking about lengths of time shorter than a unit of Planck time.<

      Not necessarily. But you do seem to think that time is a continuous quantity independent of the Planck time, which it probably isn't.

      > I am talking about there being no fact of the matter about a duration of a step or duration between steps. You could not not make any step twice as long because the very concept of duration is not required.<

      Agreed.

      >Number of steps and duration are simply not equivalent terms. A unit of Planck time has a duration. We use real numbers to model duration.<

      OK, here's where we part ways. We measure time in seconds for historical reasons and because we perceive time on scales much longer than a Planck time. If time is discrete, then a second is just some whole number of Planck times, approximately (5.4 x 10^44). In the same way that doubling the duration of a step makes no sense, doubling the duration of a Planck time likewise makes no sense because all of what happens in physics depends on the Planck time. Everything would take twice as long, including our perception of time, and we would notice no change. In fact, no change would have taken place at all. What you call the duration of the Planck time is actually the inverse of the duration of our arbitrary time unit, the second, as measured in Planck times. There's no reason an entirely analogous situation could not arise for observers in the kind of step-wise time environment we're discussing.

      >If you want to ignore the vast differences in these concepts then fine. Don't ask me to agree with it.<

      I'm not asking you to agree with it. I'm asking you to express the difference between your view and mine in terms I can understand. So far the two views of time seem equivalent to me.

      I think talking about the complexity of computers is a red herring. What is important is the complexity of algorithms or mathematical structures, because a universal computer is not much good to us if it doesn't have a program to run.

      For a Godless universe, the mathematical structure defining that universe is just the laws of physics. For a Godly universe, the mathematical structure defining that universe is an algorithm which computes the mind of God. It seems evident to me that the former is simpler than the latter, and that's my point.

      I of course don't agree that God is a necessary being, especially if he is defined as The One True God existing in all possible worlds. It is trivial to conceive of a world without Him and the ontological argument is very unconvincing.

      I hold to the Mathematical Universe Hypothesis, so there is no stochastic universe necessary to generate universes. All possible mathematical structures exist, including Krauss's demi-urges and universes supporting life. When I talk of probability I am really talking about the probability that our universe is Godly or Godless. Since Godly universes seem more special and less arbitrary to me, I imagine that Godless universes are vastly more common and so we are more likely to be in a Godless universe.

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    21. Hi Robin,

      The above post of mine was written before your latest was moderated. In that post I have made a few points that probably make much of your latest post irrelevant, in that I think the complexity of computers is beside the point and I reject the idea of a stochastic process producing universes (instead all universes simply exist).

      >So your starting simplicity is already as complex as the most powerful computer possible.<

      OK, so this is now beside the point. Nevertheless, I just want to point out that Conway's life in itself does not usually spontaneously produce a universal computer within it. Universal computers have to be designed and built by hand. In my view, they are more complex than the universe that contains them. It takes only a few words to describe the Conway's Life universe in terms of its rules. It takes a massive detailed diagram to describe a Conway's Life implementation of a Universal Computer.

      > In The Grand Design Stephen Hawking says that it has been estimated that the simplest self replicator on Game of Life would be approximately 10 trillion squares (based on work by Von Neumann).<

      It depends on what you mean by self replicator. There are plenty of simple self replicators, although I agree these would not evolve since they are entirely predictable and do not mutate.

      >the simplest source of complexity we know if really is a computer<

      The simplest source of complexity is not a computer. The Mandelbrot set for instance is described by extraordinarily simple rules but has breathtaking complexity.

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    22. A Mandlebrot set generator is more complex than the simplest computer and could not be implemented without a computer and in any case a fractal is *not*, by definition, any more complex than the program which generates it.

      Again, it is meaningless to talk about a Conway's Life implementation of a Universal Computer because Conway's Life *is* a Universal Computer.

      The logic that describes Game of Life is the logic that describes a universal computer.

      And as I pointed out before it is not even the simplest Universal Computer. The rules of the simplest Universal Computer could be described in, as I said before, 32 bits - it is a simple binary gate.

      As you said, computers such as Life require programs - but there are no simple rules that create complexity without a cost.

      Any simple rules that create complexity either have to be programmed or else involve a massive amount of trial and error - mostly error before they will produce complexity.

      That is the point of Krauss's stochastic search - to find complexity amid the noise.

      Do you think that you can dispense with the noise?

      If you say that all Universes simply exist, how does that not involve starting with maximal complexity?

      And it is not true to say that Universal Computers have to be designed and built by hand. You can implement the logic of a TM and therefore you are a Universal Computer - and you were not designed and built by hand.

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    23. Hi Robin,

      I didn't say a Mandelbrot set generator. I said the Mandelbrot set.

      I think I see one potential source of confusion. You imagine that a computational process needs a physical computer in order to exist. I disagree. For a self-contained mathematical object to exist outside of our universe, it needs no physical computer. It is identical to the 'laws of physics' of it's 'universe'. The Mandelbrot set is a wonderful example of staggering complexity arising from very simple rules.

      >Again, it is meaningless to talk about a Conway's Life implementation of a Universal Computer because Conway's Life *is* a Universal Computer.<

      No it isn't, not without distorting terms beyond meaning. By that logic, the universe is a computer, your brain is a computer, a bag of atoms is a computer and in fact anything with which you could conceivably build a turing machine is a computer. When Conway's Game of Life was shown to be Turing complete, that meant designing and creating an elaborate structure within it. Here is an example.

      >The logic that describes Game of Life is the logic that describes a universal computer.<
      Just wrong.

      > it is a simple binary gate.<
      A binary gate is not a universal computer.

      >Any simple rules that create complexity either have to be programmed or else involve a massive amount of trial and error - mostly error before they will produce complexity.<

      Ok, so why not embrace that and accept a staggering amount of error? In any case, if all possible mathematical structures exist, then it doesn't matter how many are uninteresting. Complex, apparently designed structures are inevitable needles in the haystack.

      >If you say that all Universes simply exist, how does that not involve starting with maximal complexity?<

      Because complexity is not the same as "amount of stuff". More "stuff" is often less complex than less stuff. Which is more complex, a block of marble, or 100 intricate statues carved from it? Which would take more bits to communicate to you: the entire range of numbers between 10^6 and 10^9 or 1,000 specific such numbers, randomly selected?

      The idea that all possible mathematical structures exist is the block of marble. It is not maximal but minimal complexity. If there were a distinction between the real mathematical structures and the unreal mathematical structures that would be a more complex situation, needing either to enumerate which structures are real or define some rule to distinguish them.

      >You can implement the logic of a TM and therefore you are a Universal Computer - and you were not designed and built by hand.<

      I didn't say all computers have to be built by hand. I said that Conway's Life doesn't spontaneously produce Turing machines unaided and so is not itself a Universal Computer. The fact that I evolved is just an example of complexity arising from simple rules.

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    24. Hi Disagreeable Me,

      You are just plain wrong. Conway's Game of Life *is* a Universal Computer. It has been proven to be universal - it can do any computation that any computer can.

      It would be just as meaningful for you to say that a Turing Machine is not a Universal Computer because it does not spontaneously generate lambda calculus or a universal register machine.

      And there are simpler universal computers than GoL.

      And yes, a two input binary gate with just the right set of rules *is* a universal computer and has been proven to be so.

      The stunning simplicity of a universal machine is hard to accept but it really is the case.

      Now to the Mandelbrot set. The confusion is all yours. I said that a Mandelbrot set is no more complex than a Mandelbrot set generator.

      So it is simply not an example of a few rules producing complexity. It is merely an example of a few rules producing intricacy.

      You are making the mistake of which you accuse me. Complexity is not simply more stuff.


      DM said: "Ok, so why not embrace that and accept a staggering amount of error? "

      I never said we shouldn't. But don't pretend it does not cost anything in terms of complexity. Don't pretend it comes for free.

      As to your conjecture - if every "mathematical structure" existed then the block of marble would exist and every figure cut from it would exist and every single figure that could possibly be cut from the marble would exist.

      This would not be complex if there was some simple operation which could generate all of these things.

      If so then that same operation would have to generate itself or else it would represent some minimal level of complexity. I am assuming that you can see the problem with the former.

      So essentially you have just altered Krauss stochatic process to an enumeration and that enumeration represents the complexity of your proposal.

      So where does that complexity come from?

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    25. By the way:

      Disagreeable Me wrote: "Universal computers have to be designed and built by hand. In my view,"

      Disagreeable Me wrote: "I didn't say all computers have to be built by hand."

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    26. Hi Robin,

      >Conway's Game of Life *is* a Universal Computer. It has been proven to be universal - it can do any computation that any computer can.<

      Nope. It has been proven that you can build a universal computer in Conway's life. That's not to say that it *is* a universal computer, any more than it *is* a glider or it *is* a replicator or it *is* a spaceship.

      Game of Life *is* a universal computer in the same way that a random collection of quarks and electrons are a computer. You can use them to build a computer but they are not themselves the computer in their default state.

      This is a semantic debate only, surely. I just reject what you mean by "is a computer" because it's practically meaningless and ignores the difference between something that can actually do calculations by default and something that can be used to build something that can do calculations. I don't think there is any empirical disagreement, is there?

      >It would be just as meaningful for you to say that a Turing Machine is not a Universal Computer because it does not spontaneously generate lambda calculus or a universal register machine.<
      A Turing Machine is ready to do calculations by default. All it needs is a program. The Game of Life needs an elaborate and complex structure to be designed and then it still needs a program.

      >And yes, a two input binary gate with just the right set of rules *is* a universal computer and has been proven to be so.<

      I think this is confused. I think you are possibly alluding to the fact that it has been shown that NAND gates are all you need to build any digitial logic circuit, but a single NAND gate is not a universal computer. It's a component, many of which can be used to build a universal computer. What you have said is analogous to claiming that an atom is a universal computer because computers are built of atoms. If that's not what you're talking about then a reference would be helpful for me to understand you.

      >I said that a Mandelbrot set is no more complex than a Mandelbrot set generator.<
      I'm not so sure about that. The Mandelbrot set is arguably more complex than some of the quite short programs that can generate it.

      >So it is simply not an example of a few rules producing complexity. It is merely an example of a few rules producing intricacy.<

      Hmm, you might be right. Can you distinguish between complexity and intricacy so I can mull this over? It might be that it is a bad example.

      >This would not be complex if there was some simple operation which could generate all of these things.<

      No such operation is needed. On mathematical Platonism, all of these things simply exist. They couldn't not exist.

      You quoted me out of context. I'll assume this was down to a misunderstanding rather than deliberate misrepresentation.

      "Conway's life in itself does not usually spontaneously produce a universal computer within it. Universal computers have to be designed and built by hand."

      Clearly, in context, what I meant was "universal computers [in Conway's Game of Life] do not appear spontaneously but have to be built by hand. Now, universal computers might evolve in the GoL the way I evolved in this universe, but it seems unlikely, and you'd need to come up with some plausible mechanism for this evolution to get started spontaneously to change my mind.

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    27. A Mandelbrot set is no more complex than the program which generates it by any known definition of complex.

      And you are completely wrong and hopelessly confused about universality.

      Game of Life is universal. It does do calculations by itself. It runs programs directly.

      Your confusion is that GoL can and does run programs.

      It just could not run a program designed for a Turing Machine without first implementing a Turing Machine.

      Similarly A Turing Machine could not run a program designed for a universal register machine unless it first implements a universal register machine.

      That does not mean that it is not a universal computer.

      A cellular automaton which was not a universal machine could not implement a TM or a universal register machine or any of the other equivalent accepted definitions of universal computation, *no matter what program you gave it"

      That is the difference. The game of life is a universal computer.

      Now I did not say that any logic gate was a universal computer I very explicitly stated that I was not saying that. I said that a two input logic gate which used a particular rule was universal (Wolfram's Rule 110).

      And really, if you can't accept that then you are just talking complete nonsense.

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    28. Oh, and by the way, not every Turing Machine is a universal computer.

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    29. And I should point out that, without that enumeration then technically you are back to the maximally complex necessarily existing entity like the Abrahamic God.

      From there on I guess that we just have to work out the probability between being in one of the infinitely many god created versions of this universe and the infinitely many non-god created versions of it.

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    30. Hi Robin,

      >A Mandelbrot set is no more complex than the program which generates it by any known definition of complex.<

      Would you therefore say the Mandelbrot set is no more complex than the equation that defines it? I would not. Complexity has a meaning related to intricacy and number of parts working together in consistent yet not entirely predictable ways. The equation of the Mandelbrot set itself is very simple. It can be expressed with only 10 symbols. The intricacy and surprising patterns, whorls and curlicues we see in the set cannot be so easily described. The complexity only arises when we explore what the equation entails, that's what I mean by more complex.

      Yes, that complexity arises from the simple equation, so in a sense the set IS that equation, and so can be no more complex than it on that interpretation. But by that logic a human brain is no more complex than the laws of physics which gave rise to it, which to me seems untrue.

      >Your confusion is that GoL can and does run programs. <
      It doesn't meaningfully run programs without first building a machine within it out of live and dead cells. It just evolves according to the rules of the GoL, which are not generally useful for computation without some design work first. If you think I'm wrong then a reference would be appreciated.

      >Similarly A Turing Machine could not run a program designed for a universal register machine unless it first implements a universal register machine.<

      Of course. No machine can run a program that was not written in a language it understands. A universal computer is any machine that can run a program written in a language for it. I suppose I can see how you could construe the GoL as a computer by counting the cells making up a computer within GoL as a part of the programming language, but again, that seems to be like saying that a bag of atoms is a computer because computers can be made of atoms. Perhaps you could tell me whether you think a bag of atoms is a computer and if not explain the difference between this and the GoL.

      >A cellular automaton which was not a universal machine could not implement a TM or a universal register machine<

      This is the problem. You're saying it *is* a universal machine and I'm saying it can *implement* a universal machine. Here you seem to be making both claims. Again, do you think there is any empirical difference between us or do we have different semantics?

      >I very explicitly stated that I was not saying that<
      But you didn't explicitly state what it was you did mean, leaving me to guess.

      Woflram's Rule 110 is indeed a universal computer, but it is not a two input logic gate and I don't know where you get the idea that it is. Every step of the computation can take essentially infinite inputs across infinite cells, and locally every cell takes three inputs.

      > not every Turing Machine is a universal computer.<

      My bad. When I say Turing Machine I mean Universal Turing Machine.

      >without that enumeration then technically you are back to the maximally complex necessarily existing entity like the Abrahamic God.<

      I have said I believe all possible mathematical structures exist, so I'm not "without that enumeration".

      >we just have to work out the probability between being in one of the infinitely many god created versions of this universe and the infinitely many non-god created versions of it.<

      OK, as long as you remember that two infinities are not necessarily the same. There are infinitely many integers divisible by a million and infinitely many integers divisible by two, but an arbitrary integer is much more likely to be divisible by two than a million. Similarly, as the laws governing a Godless universe are much simpler than the laws governing a Godly universe, an arbitrarily chosen universe is much more likely to be Godless.

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    31. You admit that Rule 110 is a universal computer but not Game of Life? Very peculiar But you have at least admitted that there is a very simple universal computer and our only disagreement is whether or not we consider the cell's current state as an input which is just semantic - two or three input depending on this definition.

      Rule 110 is obviously simpler than GoL and so our discussion of GoL is irrelevant. Nonetheless you say that the GoL evolves according to the rules of the GoL. The same can be said of any automaton including a Turing Machine.

      So would you then say that a Turing Machine is not a universal computer because it evolves according to the rules of a Turing Machine?

      Of course not.

      And how do you think that you can even emulate TM on GoL? By first giving it a program.

      The fact the GoL can implement a Turing Machine does not imply that it *must* implement a TM in order to do any calculation. That only serves as a proof that GoL is universal.

      A universal machine is an automaton that is capable of doing any calculation that any other machine can - and GoL satisfies that criterion.

      And you ask me to explain the difference between a mathematical description of an automaton that can, given the right program, can do any calculation whatsoever and a bag of atoms?

      The fact that you even ask the question seems to indicate that it is useless even trying to explain the answer.

      You have simply made a category error. The more meaningful question is the difference between GoL and the rules by which atoms work. The answer is that it depends upon whether those rules are universal. And I don't think anybody knows that.

      But never mind - you refuse to admit that a particular cellular automaton is a universal computer, but you have admitted that a simpler cellular automaton is a universal computer

      Let's go with that.

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    32. So you claim that the rules governing a Godless Universe are much simpler than the rules governing a Godly Universe.

      On what do you base that?

      You have admitted that the simplest universal computer is one where the logic can be described in 32 bits.

      In your conjecture there are infinitely many of these with infinitely many programs.

      We don't know the base complexity of the simplest rules that can create a natural universe. I doubt that they are simpler entities than Rule 110 but I don't know that and neither do you.

      Personally I doubt whether anything simpler than Rule 110 will be capable of generating any sort of complexity. We do not have any examples of this.

      However we do know that your conjecture will, by definition, imply demigods capable of understanding the mathematics underlying our universe and therefore creating one because this is logically possible.

      We also know that it is logically possible that they will create arbitrarily many of these universes and therefore this will happen in your conjecture.

      We also know that they will be capable of creating arbitrarily many other digital demigods and therefore this will happen under your conjecture and of course it is logically possible that each spawned demigod will spawn arbitrarily many other demigods and arbitrarily many other universes.

      If everything that can happen does happen in your conjecture then this will happen.

      So the question of the relative complexity is subsumed by the fact that once we have our first digital demigod then there is zero improbability involved in any subsequent demigod or demigod-created universe.

      Thus they will definitely outnumber natural universes.

      So, under your conjecture, we should expect to be living in a digital-demigod created universe and hope that it is not one that really is going to send to hell for not praying at it (since under your conjecture such universes must exist).

      And since the rules of a digital-demigod created universe will be entirely under the control of the digital demigod then it can alter those rules as it pleases and therefore there can be miracles in those universes.

      If you are right there will definitely be universes that are just like ours except that our heads will grow twice as big every second Thursday and return to normal size at exactly 7.26 that evening.

      Luck, then, that we don't live in that universe.

      And there will be a universe that is just like ours except that, tomorrow at 2.33 pm Mothra will destroy Seattle and then Seattle will reassemble itself next day.

      Under your conjecture that universe definitely exists and the people in that universe will be conscious just like you and me.

      Do you agree?

      Delete
    33. So, under the Mathematical Universe Hypothesis it is vastly unlikely that I am not living in a universe created by a digital demigod who could alter the perceived laws of physics at will.

      So we have to think about the kinds of miracles that could conceivably happen to me. Too large to number, almost anything could happen. They will certainly outnumber the ways that my day could go if the apparent laws of physics continued to apply.

      So the number of universes where miraculous events are an every day occurrence vastly outnumber those where they are not.

      So it is vastly unlikely that I will get through today. or any day for that matter, without many miraculous events happening to me.

      But I get through every day without any event happening that was not according to the perceived laws of physics.

      So the Mathematical Universe Hypothesis is false.

      If Max Tegmark’s reasoning behind this hypothesis is sound then the external reality hypothesis is also false.

      Personally I think it is his reasoning that is false.

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    34. Hi Robin,

      It's great to have an opponent in discussing ideas like the MUH specifically, as I don't think it's empirically testable and so the only way to test the idea is to have a discussion with someone who disagrees.

      I think one thing that is true of me is that I will argue about anything if I see a problem with it, whether or not it supports my cause. So don't be too surprised to see me arguing against the complexity of one specific computer but for it in another, it depends on how I see that case.

      I agree there is a certain inconsistency in my interpretation of Rule 110 as a computer and not of the GoL. I think this comes down to the fact that it is much more natural to interpret it this way because it is possible to do computation with Rule 110 by entering a program coded as a sequence of ones and zeros. It is not really possible to do that with GoL without first constructing an elaborate structure. Nevertheless, this structure is also composed of ones and zeros so it's hard to make a case that the difference is substantial. Nevertheless, I think it is certainly an unusual view to regard the GoL as a whole as a computer. But OK, let's shelve that and I will admit that the GoL can be considered to be a computer.

      >the difference between a mathematical description of an automaton that can, given the right program, can do any calculation whatsoever and a bag of atoms<

      However I do want you to understand where I'm coming from. I don't think the difference is as obvious as you seem to think. GoL can compute anything given the right structure and program. A bag of atoms can compute anything if they are arranged properly first. By default, neither are much use, but given some work each can be used to build a computing engine. To me the analogy seems reasonably clear, although perhaps it would be more direct if I said that this universe is a universal computer because it is possible to do computations in it. Now this analogy I think is perfect.

      >The more meaningful question is the difference between GoL and the rules by which atoms work. The answer is that it depends upon whether those rules are universal.<

      Well, they are universal. Obviously. Because the rules by which atoms work can be used to drive a physical computer.

      Anyway, what does it get you to show that there is a very very simple computer? OK, it contradicts what I said earlier, which was "The universe can essentially be defined by the laws of physics, which though currently not completely understood, are almost certainly much simpler than a computer.". When I said this, I was thinking of a physical computer, made of trillions of atoms arranged in a very specific way. I do view this physical object as more complex than the laws of physics of the universe. I agree with you that a mathematical abstraction of a computer is much simpler than the laws of physics.

      So, we are agreed that (logical) computers are simple. Indeed, let's go with that.

      Delete
    35. >So you claim that the rules governing a Godless Universe are much simpler than the rules governing a Godly Universe.<

      The "laws of physics" for a Godless universe are much like those in our universe. Sure, there will be lots of arbitrarily complex universes with very complex laws of physics, but for reasons I won't discuss right now (unless you're interested) I think they are unlikely to support life. So take this universe as a sample of what a typical life-supporting universe might be like.

      The "laws of physics" for a universe created by and interacting with a God who did not evolve but simply exists of his own nature must account for that God. Now, instead of defining physical constants and the relationships between matter and energy, the "laws of physics" instead must comprise an algorithm corresponding to a perfect, infinitely intelligent, infinitely benevolent mind. This may just be my intuition talking, but I think such an algorithm is likely to be more complicated than the equations of the physics of this universe.

      >You have admitted that the simplest universal computer is one where the logic can be described in 32 bits.<

      Actually I think you'll find it only needs 8 bits. You don't need to specify the input combinations, they are implied by the ordering of the output bits.

      >In your conjecture there are infinitely many of these with infinitely many programs.<

      Well, OK, but I don't think you need the computers. I think you only need the programs. A computer is a way to process a program. But if the program *is* the universe then no computer is necessary. The mathematical structure of the program is all you need to define what happens in that universe. But yeah, infinitely many programs...

      >Personally I doubt whether anything simpler than Rule 110 will be capable of generating any sort of complexity.<
      You're probably right.

      >your conjecture will, by definition, imply demigods capable of understanding the mathematics underlying our universe and therefore creating one because this is logically possible.<
      Yup.

      >it is logically possible that they will create arbitrarily many of these universes and therefore this will happen in your conjecture.<
      Yup

      >each spawned demigod will spawn arbitrarily many other demigods and arbitrarily many other universes.<
      Yup.

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    36. >So the question of the relative complexity is subsumed by the fact that once we have our first digital demigod then there is zero improbability involved in any subsequent demigod or demigod-created universe.<

      Well, kind of, in that the existence of all these options is necessary, so therefore no improbability. But the chance that any individual observer exists in a Godly universe is still near zero, because there are vastly more ways for a universe to be Godless than Godly, because of the relative complexity of those universes.

      >Thus they will definitely outnumber natural universes.<

      Nope.

      Back to my number analogy. This is how I see your argument:

      For every number which is a multiple of a million, there are an infinite number of multiples of that number, and for each of those multiples, an infinite number of multiples ad infinitum. So, once we have our first number that is a multiple of a million, then there is zero improbability of there not being other numbers that are a multiple of a million. Therefore, for any arbitrarily chosen number, it is almost certainly a multiple of a million.

      >If you are right there will definitely be universes that are just like ours except that our heads will grow twice as big every second Thursday and return to normal size at exactly 7.26 that evening.<

      I'm not so sure about that. That implies an absolute concept of time, which according to relativity is problematic. The universe you describe is probably incoherent. You would also need to describe precisely what distinguishes a human head from any other arbitrary lump of matter. In short, you don't really get to let your imagination run wild and suppose that any kind of crazy universe exists because humans are good at imagining logically incoherent scenarios.

      >And there will be a universe that is just like ours except that, tomorrow at 2.33 pm Mothra will destroy Seattle and then Seattle will reassemble itself next day.<

      Maybe, but again, probably incoherent. How does the universe distinguish Seattle from other aggregations of matter in order to spontaneously reassemble itself? It seems unlikely that this scenario can be decomposed easily to a set of equations the way our universe can be.

      Finally, I would like to point out one subtlety in how I view things. Somewhere out there in the mathematical multiverse there is a creator being who has created a universe just like ours. As long as he doesn't interact with the universe, then that universe is identical to ours. In my view, this means that it *IS* our universe. But this doesn't mean that our universe has a creator any more than Mandelbrot created the Mandelbrot set. He discovered it. And in fact there must be an infinite number of 'creators' who 'discovered' our universe, so our universe can have no single creator, (as long as there are no miracles). I say that not to refute any of your points in particular but just to explain something important about my view.

      Delete
    37. [Massimo: this is a repost as I fear that since previous comments turned up but this did not that it did not submit properly. Please delete this if it is a double post]

      >So the question of the relative complexity is subsumed by the fact that once we have our first digital demigod then there is zero improbability involved in any subsequent demigod or demigod-created universe.<

      Well, kind of, in that the existence of all these options is necessary, so therefore no improbability. But the chance that any individual observer exists in a Godly universe is still near zero, because there are vastly more ways for a universe to be Godless than Godly, because of the relative complexity of those universes.

      >Thus they will definitely outnumber natural universes.<

      Nope.

      Back to my number analogy. This is how I see your argument:

      For every number which is a multiple of a million, there are an infinite number of multiples of that number, and for each of those multiples, an infinite number of multiples ad infinitum. So, once we have our first number that is a multiple of a million, then there is zero improbability of there not being other numbers that are a multiple of a million. Therefore, for any arbitrarily chosen number, it is almost certainly a multiple of a million.

      >If you are right there will definitely be universes that are just like ours except that our heads will grow twice as big every second Thursday and return to normal size at exactly 7.26 that evening.<

      I'm not so sure about that. That implies an absolute concept of time, which according to relativity is problematic. The universe you describe is probably incoherent. You would also need to describe precisely what distinguishes a human head from any other arbitrary lump of matter. In short, you don't really get to let your imagination run wild and suppose that any kind of crazy universe exists because humans are good at imagining logically incoherent scenarios.

      >And there will be a universe that is just like ours except that, tomorrow at 2.33 pm Mothra will destroy Seattle and then Seattle will reassemble itself next day.<

      Maybe, but again, probably incoherent. How does the universe distinguish Seattle from other aggregations of matter in order to spontaneously reassemble itself? It seems unlikely that this scenario can be decomposed easily to a set of equations the way our universe can be.

      Finally, I would like to point out one subtlety in how I view things. Somewhere out there in the mathematical multiverse there is a creator being who has created a universe just like ours. As long as he doesn't interact with the universe, then that universe is identical to ours. In my view, this means that it *IS* our universe. But this doesn't mean that our universe has a creator any more than Mandelbrot created the Mandelbrot set. He discovered it. And in fact there must be an infinite number of 'creators' who 'discovered' our universe, so our universe can have no single creator, (as long as there are no miracles). I say that not to refute any of your points in particular but just to explain something important about my view.

      Delete
    38. Lets deal with fhe time and matter thing. Of course there is no absolute time, I can't see where you are getting that from. There is no time at all, only a mathematical construct which certain observers interpret as time. Same with matter. A pure algorithm is not going to be constrained by relativity. Why would it?

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    39. So let’s deal with the probability thing.

      The trouble is that you have said nothing new. You are still relying on that unsupported assumption about the simplicity of universes.

      I have moved on and am showing that, even if you were right about that, you would still be behind the eight ball.

      Here is what we are comparing:

      1. Infinitely many ways to start a some sort of a natural universe
      2. Infinitely many ways to start each specific digital universe

      So they are not really equal.

      And I am understating it. For a start, for each universal computer there will be infinitely many mathematically distinct strings which are equivalent algorithms for each specific universe.

      Any algorithm can run on top of a continuous system so there can be infinitely many machines with different trigger ratios (and since these are continuous this will be an uncountable infinity).

      And for each trigger ratio there can be an infinite variation of local fluctuations, again uncountable.

      There are just too many distinct mathematical structures which can implement any particular algorithm for the natural universe to compete.

      So let’s take an example - this universe we are both observing and having this discussion in. Under MUH there is, with a probability of 1, an uncountable infinity of uncountable infinities of infinitely many mathematically distinct digital demigods dedicated to the task of creating arbitrarily many universes of the type we are observing in order that we can have this discussion and arbitrarily many more digital demigods dedicated to the same task.

      And there are multipliers in the variations we can’t see, like teapots orbiting Aldebaran or sugar bowls orbitting Proxima Centauri.

      So yes, it really is overwhelmingly improbably under MUH that we are in a natural universe.

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    40. The next issue is whether or not the digital demigods can create miracles in their universes.

      Your objection appears to be that the miracles would contravene natural laws like relativity.

      But that is rather the point of miracles.

      The created universe does not need to be self consistent as it has a mind doing the adjustments.

      Why would enlarging heads every second Thursday require an absolute concept of time?

      Why would demolishing and reassembling Seattle cause a problem?

      If I create a simulation of a world and make it act according to some laws of physics then I can easily remove a building and replace it with another and the world will continue with the new physical configuration. I didn’t need to calculate any equations by which this worked - I just erased the building, replaced it with another and bob’s your uncle.

      The digital demigod might have a rather more complex set of adjustments to make but it would really be under much the same principle. There is no need for him to derive a set of equations to describe the reconstruction of Seattle - he can just make it happen in any crazy order, make adjustments to the sense data reaching the people and there you are.

      Time and matter are nothing but numbers in the digital demigod universe and he just needs to replace them all with different numbers.

      So, yes, under MUH a digital demigod can and will create a universe which instantiates any crazy state of affairs that our minds can envisage and quite a lot besides.

      He can make Godzilla appear in Central Park, New York tomorrow in red hot pants, a bowler hat and dancing the macarena. And under MUH, in an uncountable infinity of uncountable infinities of infinitely many infinities of universes, a digital demigod does just that.

      Delete
    41. Hi Robin,

      My comment about absolute time was only directed at your postulation of a universe where some global event happens at regular intervals, which I understood was supposed to be a brute law of nature. If it's happening at the whim of a demigod I agree such a universe could exist. The same goes for my comments about what constitutes a head and what constitutes Seattle. All of these things are possible in a universe governed by a capricious mind, but probably not in a universe governed by simple laws.

      My view is that all universes which appear the same are the same universe. If there are two algorithmic strings which lead to identical universes in every way, then those are the same universe. Mathematical objects are built out of structure and relations, not mathematical notation. programming languages or machine code. Any two structures which are isomorphic are the same structure.

      Also, I do not think any mathematical universe needs a computer to run it. That computer would need some sort of reality to exist in, so why not let the buck stop at the universe itself. So, talking of registers and trigger ratios is beside the point. All we need to discuss is the mathematical relations of the universe itself.

      Now, with that said, perhaps you can understand while though I acknowledge that there are an infinite multitude of possible beings who could have designed this universe, as long as they do not intervene I regard them as not being part of this universe. They did not create it, they merely discovered the mathematical object describing it the same way any mathematician does when discovering any mathematical object. This universe exists independently of them and does not exist because of them.

      If they intervene, then this universe is no longer accurately described by the laws of physics, but is instead ultimately derived from the mathematical object describing the mind of a specific demigod.

      My contention is that an arbitrarily chosen mathematical object is much more likely to support conscious life through relatively simple laws of physics than it is to correspond to the mind of a digital demigod, because the latter is much more complex (perhaps "special") and less arbitrary than the former. Any algorithm describing a conscious mind is so complex, so intricate, so apparently designed or evolved, that it is inconceivable that an arbitrarily chosen mathematical object could describe it. Simple laws, on the other hand, often lead to complexity in surprising ways, and these are not particularly sensitive to how the original laws are chosen. Numerous cellular automata and other mathematical constructs demonstrate that there exists an inexhaustible supply of entirely different sets of rules that produce complexity and spontaneous organisation. Therefore I believe that universes determined by conscious minds exist in negligible quantities compared to those determined by simple laws.

      Delete
  24. Massimo

    > The job of philosophy of science, as I see it, is to make sense of science and occasionally to criticize its methods or findings, especially but not only when they have social consequences. <

    To make sense of science? As in asking meta-questions about the nature of its claims, its language, its methods, etc.?

    This seems okay to me, and it is something which is appropriately done both by active scientists and by scientifically-trained outsiders (who may or may not see themselves as philosophers).

    > ... to criticize its methods or findings... <

    I can imagine cases where the methods of a social science may be usefully criticized by someone without specialist training in that particular social science, but this is not the case with a mature science like physics. In such cases only those trained in the science in question have the knowledge to criticize its methods or findings with any authority. So for example (as you admit) your views on string theory don't have any special authority, whereas your views on questions of biology would (presumably) carry more weight.

    Your earlier reference to public funding is unexceptionable: ideally we all should have a say on how tax monies are spent. But the reference to "social consequences" takes us into ethics, and I am not prepared to cede any privileges to philosophers in that area. (Meta-ethics maybe, but not applied ethics.)

    In general I would say that your defense of philosophy on this site and elsewhere is not particularly effective, mainly because it can all too easily be interpreted in psychological and personal terms – i.e. as being associated with a personal desire to exert influence on public policy questions and more generally on the way other people think and act. A more Machiavellian operator would try harder to disguise these motivations!

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  25. The whole notion of “falsifiability” is meaningless in mainstream physics.

    The particle does not always travel through a single slit in a double slit experiment.

    How do you falsify the above statement? You place detectors at the entrances, throughout or at the exits to the slits.

    When you do this the particle is always detected entering, traveling through and exiting a single slit.

    The notion the particle does not travel through a single slit is refuted by the evidence. It’s been falsified.

    So, what does mainstream physics do? They ignore the physical evidence which refutes the notion the particle does not travel through a single slit and state that something else occurs when you don’t detect the particle.

    What is that something else? Well, now mainstream physics can make up all sorts of stuff about a multiverse or many worlds or whatever nonsense it wants because you can’t falsify made up nonsense.

    The notion the particle does not travel through a single slit is falsified by the physical evidence.

    Physics is supposed to be about understanding what occurs physically in nature and the evidence which supports what we think is occurring physically in nature.

    In a boat double slit experiment the boat travels through a single slit and the bow wave passes through both. If the boat is moving fast enough the bow wave will create wave interference upon exiting the slits which will alter the direction the boat travels. If you place pilings at the exits to the slits in order to detect the boat the boat will get knocked around by the pilings, lose its cohesion with its bow wave, and continue on the path it was traveling.

    Is the question the boat does not always travel through a single slit falsifiable?

    When you place pilings at the entrances to the slits the boat is always detected entering a single slit. When you placing pilings anywhere within the slits the boat is always detected within a single slit. When you place pilings at the exits to the slits the boat is always detected exiting a single slit.

    The question the boat does not always travel through a single slit has been falsified.

    Now, just because when you place a screen in front of you so you can’t see the boat double slit experiment and the boat makes an interference pattern on the shore when it is not detected is not evidence the boat did not travel through a single slit. It is indirect evidence it is the bow wave which passes through both slits.

    Most of the nonsense associated with mainstream physics goes away when you understand aether has mass which physically occupies three dimensional space and is physically displaced by the particles of matter which exist in it and move through it?

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    Replies
    1. That's pretty good. I've always thought (since high school I'd say) that physics (and, to a somewhat lesser degree, mathematics) is nonsense that sometimes works. It's all models and games anyway.

      Delete
    2. It's not physics and mathematics which is nonsense in and of itself. I think the issue is that most physicists are conceptually deficient mathematicians who can't stop themselves from making stuff up.

      The main problem with mainstream physics is when they went the Copenhagen route instead of the de Broglie wave mechanics/double solution route and also decided to do away with the aether.

      'New 'Double Slit' Experiment Skirts Uncertainty Principle'
      http://www.scientificamerican.com/article/new-double-slit-experiment-skirts-uncertainty-principle/

      "Intriguingly, the trajectories closely match those predicted by an unconventional interpretation of quantum mechanics known as pilot-wave theory, in which each particle has a well-defined trajectory that takes it through one slit while the associated wave passes through both slits."

      'Quantum mechanics rule 'bent' in classic experiment'
      http://www.bbc.co.uk/news/science-environment-13626587

      'For his part, Professor Steinberg believes that the result reduces a limitation not on quantum physics but on physicists themselves. "I feel like we're starting to pull back a veil on what nature really is," he said. "The trouble with quantum mechanics is that while we've learned to calculate the outcomes of all sorts of experiments, we've lost much of our ability to describe what is really happening in any natural language. I think that this has really hampered our ability to make progress, to come up with new ideas and see intuitively how new systems ought to behave."'

      Aether has mass, physically occupies three dimensional space and is physically displaced by particles of matter.

      A moving particle has an associated aether displacement wave. In a double slit experiment the particle travels through a single slit. It is the associated wave in the aether which passes through both. As the aether wave exits the slits it creates wave interference. As the particle exits a single slit the direction it travels is altered by the wave interference. This is the wave piloting the particle of pilot-wave theory. Strongly detecting the particle causes a loss of coherence between the particle and its associated wave in the aether.

      What waves in a double slit experiment is the aether.

      'Interpretation of quantum mechanics by the double solution theory - Louis de BROGLIE'
      http://aflb.ensmp.fr/AFLB-classiques/aflb124p001.pdf

      “When in 1923-1924 I had my first ideas about Wave Mechanics I was looking for a truly concrete physical image, valid for all particles, of the wave and particle coexistence discovered by Albert Einstein in his "Theory of light quanta". I had no doubt whatsoever about the physical reality of waves and particles.”

      “any particle, even isolated, has to be imagined as in continuous “energetic contact” with a hidden medium”

      The hidden medium of de Broglie wave mechanics is the aether. The “energetic contact” is the state of displacement of the aether.

      "For me, the particle, precisely located in space at every instant, forms on the v wave a small region of high energy concentration, which may be likened in a first approximation, to a moving singularity."

      A particle is a moving singularity which has an associated aether displacement wave.

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    3. Hi Mike,

      You seem awfully certain that this is the right interpretation. Why is that? It does seem to me to have some problems.

      In particular, it seems to assume that both the wave and the particle exist as distinct entities. Why do we need the particle at all if the wave explains everything we observe?

      Also, doesn't assuming that the aether exists pose a problem for relativity in that it implies that there is a privileged frame of reference (i.e. being at rest with respect to the aether)?

      For your particular argument, I would make a number of points.

      >How do you falsify the above statement? <

      You falsify it by showing that it does travel through a particular slit in the case where we had previously assumed that it goes through more than one, i.e. when we observe an interference pattern. Observing it passing through a slit without showing an interference pattern does not falsify the original proposition.

      >If you place pilings at the exits to the slits in order to detect the boat the boat will get knocked around by the pilings, lose its cohesion with its bow wave, and continue on the path it was traveling.<

      I think this analogy fails. Of course it is possible to detect a bow wave without causing the boat to lose cohesion. In QM, any observation no matter how subtle at a particular slit means no interference whatsoever. This simply isn't true of the boat. That doesn't mean that your interpretation is incorrect, it only means that the analogy is relatively useless.

      >Is the question the boat does not always travel through a single slit falsifiable?<

      Yes, because it's possible to observe the boat going through a single slit while preserving the interference pattern.

      >Aether has mass, physically occupies three dimensional space and is physically displaced by particles of matter.<

      If it has mass and is physically displaced then I would have thought that it must to some extent resist the passage of particles through it, as it takes force to displace something with mass.

      None of this is to say I am certain you are wrong, but I don't see how your confidence is justified, in particular since this is such a minority view among physicists.

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    4. > In particular, it seems to assume that both the wave and the particle exist as distinct entities.

      "The word 'ether' has extremely negative connotations in theoretical physics because of its past association with opposition to relativity. This is unfortunate because, stripped of these connotations, it rather nicely captures the way most physicists actually think about the vacuum. . . . Relativity actually says nothing about the existence or nonexistence of matter pervading the universe, only that any such matter must have relativistic symmetry. [..] It turns out that such matter exists. About the time relativity was becoming accepted, studies of radioactivity began showing that the empty vacuum of space had spectroscopic structure similar to that of ordinary quantum solids and fluids. Subsequent studies with large particle accelerators have now led us to understand that space is more like a piece of window glass than ideal Newtonian emptiness. It is filled with 'stuff' that is normally transparent but can be made visible by hitting it sufficiently hard to knock out a part. The modern concept of the vacuum of space, confirmed every day by experiment, is a relativistic ether. But we do not call it this because it is taboo." - Robert B. Laughlin, Nobel Laureate in Physics, endowed chair in physics, Stanford University

      "any particle, even isolated, has to be imagined as in continuous “energetic contact” with a hidden medium ... If a hidden sub-quantum medium is assumed, knowledge of its nature would seem desirable. It certainly is of quite complex character. It could not serve as a universal reference medium, as this would be contrary to relativity theory." - Louis de Broglie, Nobel Laureate in Physics

      "According to the general theory of relativity space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense." - Albert Einstein, Nobel Laureate in Physics

      The relativistic ether referred to by Laughlin is the hidden sub-quantum medium referred to by de Broglie is the ether which propagates light referred to by Einstein.

      >Why do we need the particle at all if the wave explains everything we observe?

      We observe the particle.

      >In QM, any observation no matter how subtle at a particular slit means no interference whatsoever.

      Incorrect.

      'New 'Double Slit' Experiment Skirts Uncertainty Principle'
      http://www.scientificamerican.com/article/new-double-slit-experiment-skirts-uncertainty-principle/

      "Intriguingly, the trajectories closely match those predicted by an unconventional interpretation of quantum mechanics known as pilot-wave theory, in which each particle has a well-defined trajectory that takes it through one slit while the associated wave passes through both slits."

      'Quantum mechanics rule 'bent' in classic experiment'
      http://www.bbc.co.uk/news/science-environment-13626587

      'For his part, Professor Steinberg believes that the result reduces a limitation not on quantum physics but on physicists themselves. "I feel like we're starting to pull back a veil on what nature really is," he said. "The trouble with quantum mechanics is that while we've learned to calculate the outcomes of all sorts of experiments, we've lost much of our ability to describe what is really happening in any natural language. I think that this has really hampered our ability to make progress, to come up with new ideas and see intuitively how new systems ought to behave."'

      >If it has mass and is physically displaced then I would have thought that it must to some extent resist the passage of particles through it, as it takes force to displace something with mass.

      Resistance, yes. Friction; no.

      The aether is, or behaves similar to, a supersolid.

      Delete
    5. >We observe the particle.<

      Not necessarily. How do you know you are not observing a wave?

      >Resistance, yes. Friction; no.<

      If there is resistance, then should we not observe particles decelerating as they pass through the aether? Otherwise what do you mean by resistance?
      >>In QM, any observation no matter how subtle at a particular slit means no interference whatsoever.

      Incorrect.<

      I don't think the experiment you cited shows me to be incorrect. They were not making measurements at the slits but at some distance from the slits, and they were not able to find the momentums of individual photons but averages for large groups of photons.

      Delete
    6. 'Double slit' experiments have been performed with C-60 molecules. That's 60 interconnected atoms. If you choose to believe those 60 interconnected atoms are detected as a wave then it is impossible for me to have a conversation with you.

      By resistance, I mean it requires energy for the particle to displace the aether. The aether returns to the particle the same amount of energy as the aether fills-in where the particle had been and 'displaces back'.

      Q. Is the particle displacing the aether or is the aether displacing the particle?
      A. Both are occurring simultaneously with equal force.

      In the experiment I referred to they were making weak measurements all over the place.

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    7. > If you choose to believe those 60 interconnected atoms are detected as a wave then it is impossible for me to have a conversation with you.<

      My understanding is that all of quantum physics and indeed all of physics is compatible with the idea that particles are actually waves. I am not competent to get into the details of how this works. If forced to speculate from my ignorance, I would imagine that a C-60 molecule is a structure composed of waves.

      >they were making weak measurements all over the place.<

      They were not making measurements at the slits.

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    8. Just to elaborate on one point, quoting myself:

      >I would imagine that a C-60 molecule is a structure composed of waves.<

      I would also imagine that the whole ensemble could be treated as a single wave while it's not interacting with anything.

      But again, I'm ignorant. The point is that yours is such a minority view, doubted by the vast majority of physicists who really do understand this stuff. As such, I think your certainty is likely to be unjustified even if you happen to be right.

      Delete
    9. When you detected an atom you are detecting a particle. When you detected a 60-molecule you are detecting 60 atoms, you are detecting 60 particles.

      The point of the experiment is that they were making weak measurements of the location of the particle and the interference pattern was still created.

      Delete
    10. If a C-60 molecule was propagating as a physical wave in a double slit experiment then when you placed detectors within the slits you would detect a certain number of atoms within each slit. This does not happen. The C-60 molecule is always detected as a single entity, as all 60 atoms.

      To simply suggest a C-60 molecule propagates as a wave is refuted by the evidence.

      This is why mainstream physics is making up all sorts of nonsense such as many worlds.

      In a double slit experiment the C-60 molecule is always detected as a single entity, as 60 interconnected atoms, because it always exists as a single entity, as 60 interconnected atoms.

      The point of this thread is to discuss falsifiability. Sean Carroll is suggesting we do away with falsifiability. He is suggesting this because mainstream physics is so completely fucked up and can't even understand the reason why the particle is always detected as a single entity, as a particle, is because it always exists as a particle.

      There is evidence of the aether every time a double slit experiment is performed; it's what waves.

      Delete
    11. Hi Mike,

      Here is how I understand the experiment.

      They placed the detectors not at the slit but at various locations past the slits where the particles could still have passed through either/both slits. The interference pattern they observed was co-located with the detector, not elsewhere. At no point did they detect particles at the slits themselves while still seeing an interference pattern.

      The paths they traced out were not for individual particles but extrapolated from measurements conducted at many points in space after the slits. These paths agreed with your interpretation of Quantum Mechanics, but also, crucially, with what is predicted by all the other interpretations given this experimental procedure. These paths are predictable from the equations alone and no particular interpretation is needed. It cannot be taken then as evidence for your interpretation.

      >When you detected an atom you are detecting a particle.<

      Well, not a fundamental particle. An atom is composed of quarks and electrons. I'm not sure it itself is a particle any more than a C60 molecule or a cat.

      >If a C-60 molecule was propagating as a physical wave in a double slit experiment then when you placed detectors within the slits you would detect a certain number of atoms within each slit.<

      I don't think this is right at all. Are you saying we should expect to see, e.g. 40 atoms in one slit and 20 in another? I really wouldn't think so, as in quantum mechanics we consider all the different ways things could go (e.g. passing through slit 1 or slit 2) with probability amplitudes for each way. The molecule spontaneously separating into a group of 40 atoms and 20 atoms and then recombining is not likely at all. The atoms are bound, or entangled or something (not sure what the correct terminology is). You don't consider them separately because they are interacting with each other as a single system.

      >To simply suggest a C-60 molecule propagates as a wave is refuted by the evidence.<

      No it isn't. We see an interference pattern. That's a wave effect.

      >nonsense such as many worlds.<

      Explain why you think it is nonsense? What about it is so self-evidently false, other than the fact that it is unintuitive?

      >because it always exists as a single entity, as 60 interconnected atoms.<

      Sure, 60 interconnected atoms which can go every possible path simultaneously between (observations/interactions), so through two slits at once.

      > the reason why the particle is always detected as a single entity, as a particle,<

      Because that's what the equations predict. We observe it as a single particle but that doesn't mean it is, or that it always is. In objective collapse theories the wavefunction collapses to a single particle. The MWI more elegantly proposes that it doesn't collapse. The particle continues to exist in a multitude of states, but when we observe it we also split into a multitude of states each observing the particle differently. It's a beautiful and relatively simple idea.

      >There is evidence of the aether every time a double slit experiment is performed; it's what waves.<

      I may agree that aether of some form exists. You could for example trivially define aether so as to mean the fabric of space, including all the various fields permeating it. That is indeed what waves. There are no electrons, just waves in the electron field which look like particles to us because of our limited ability to perceive reality directly.

      By your own example, you don't need a boat to have a wave. If everything we see can be explained by reference to waves, since all we can detect directly are the waves (as must be the case if we are detecting interference patterns), then there's no need to imagine that there is a boat at all.

      Delete
  26. Sean Carroll's tag line is, “in truth, only atoms and the void”.

    The idea which is ready for retirement is the notion of, “in truth, only atoms and the void”.

    In truth, not only is there an aether, it has mass.

    There is no such thing as non-baryonic dark matter anchored to matter. Matter moves through and displaces the aether.

    What is referred to as the the Milky Way’s dark matter halo is the state of displacement of the aether.

    What ripples when galaxy clusters collide is what waves in a double slit experiment; the aether.

    Einstein’s gravitational wave is de Broglie’s pilot-wave; both are waves in the aether.

    ReplyDelete
  27. In the SciAm article ("New 'Double Slit' Experiment Skirts Uncertainty Principle"):

    David Deutsch of the University of Oxford, UK, is not convinced that the experiment has told us anything new about how the universe works. He says that although "it's quite cool to see strange predictions verified", the results could have been obtained simply by "calculating them using a computer and the equations of quantum mechanics".

    "Experiments are only relevant in science when they are crucial tests between at least two good explanatory theories," Deutsch says. "Here, there was only one, namely that the equations of quantum mechanics really do describe reality."

    According to Deutsch there is just one concrete model (theory) that is even being considered: What he calls the equations of quantum mechanics. So there could be two different computer programs (interpretations) that simulate this model, but as long as the numerical calculations (predictions) come out the same, there's nothing more to say scientifically.

    ReplyDelete
    Replies
    1. Of course there is more to say scientifically. Either the particle always travels through a single slit or it doesn't.

      There is zero evidence the particle does not always travel through a single slit.

      The interference pattern created in a double slit experiment is not evidence the particle did not travel through a single slit. The interference pattern is indirect evidence the associated wave in the aether passed through both.

      Equations do not describe reality. Mathematical equations help determine if what is hypothesized is correct or not.

      All of the evidence is evidence aether has mass which physically occupies three dimensional space and is physically displaced by the particles of matter which exist in it and move through it.

      Delete
    2. "the equations of quantum mechanics really do describe reality."

      Not physical reality.

      Delete
    3. Quantum mechanics describes probability and the equation describes certainty, the absolute. =

      Delete
    4. Quantum mechanics describes probabilities and the equations predict the probability of any particular result; neither of which have anything to do with describing what occurs physically in nature.

      de Broglie's double solution theory describes the probabilities, defines the equations which predict the probability of any particular result and describes what occurs physically in nature.

      'Interpretation of quantum mechanics by the double solution theory - Louis de BROGLIE'
      http://aflb.ensmp.fr/AFLB-classiques/aflb124p001.pdf

      “When in 1923-1924 I had my first ideas about Wave Mechanics I was looking for a truly concrete physical image, valid for all particles, of the wave and particle coexistence discovered by Albert Einstein in his "Theory of light quanta". I had no doubt whatsoever about the physical reality of waves and particles.”

      “any particle, even isolated, has to be imagined as in continuous “energetic contact” with a hidden medium”

      The hidden medium of de Broglie wave mechanics is the aether. The “energetic contact” is the state of displacement of the aether.

      "For me, the particle, precisely located in space at every instant, forms on the v wave a small region of high energy concentration, which may be likened in a first approximation, to a moving singularity."

      A particle is a moving singularity which has an associated aether displacement wave.

      In a double slit experiment the particle travels a well defined path which takes it through one slit. The associated wave in the aether passes through both. As the aether wave exits the slits it creates wave interference. As the particle exits a single slit the direction it travels is altered by the wave interference. This is the wave piloting the particle of pilot-wave theory. Detecting the particle strongly exiting a single slit destroys the coherence between the particle and its associated wave in the aether.

      Delete
    5. There is only one equation that truly matters, One that unites everything, an equation that defines is, that defines truth, a single simple equation for absolute: The equation is =

      Delete
    6. Which has nothing to do with describing what occurs physically in nature.

      Aether has mass which physically occupies three dimensional space and is physically displaced by particles of matter.

      There is no such thing as non-baryonic dark matter anchored to matter. Matter moves through and displaces the aether.

      What is referred to as the Milky Way's dark matter halo is the state of displacement of the aether.

      Displaced aether pushing back and exerting inward pressure toward matter is gravity.

      More correctly, the state of displacement of the aether is gravity.

      A moving particle has an associated aether displacement wave. In a double slit experiment the particle travels through a single slit and the associated wave in the aether passes through both.

      Delete
    7. The equation of nature is self-evident but for many or most it has yet to be seen. As for waves and particles, they are one or the same.
      And the speed of dark matter equals the speed of light.
      =

      Delete
    8. Then explain what occurs physically in nature in a double slit experiment.

      Can't, can you?

      In a double slit experiment the particle travels a well defined path which takes it through one slit. The associated wave in the aether passes through both. As the aether wave exits the slits it creates wave interference. As the particle exits a single slit the direction it travels is altered by the wave interference. This is the wave piloting the particle of pilot-wave theory. Detecting the particle strongly exiting a single slit destroys the coherence between the particle and its associated wave in the aether.

      Double slit experiments have been performed with C-60 molecules. That's 60 interconnected atoms. When a double slit experiment is performed with C-60 molecules the complete molecule, all 60 atoms, are always detected as a single entity. The C-60 molecule is always detected as a single entity because it always exists as a single entity. It is the associated wave in the aether which passes through multiple slits.

      Delete
    9. Waves and particles are not one or the same. When a double slit experiment is performed with a C-60 molecule the C-60 molecule is always detected as a single entity because it always exists as a single entity.

      'Interpretation of quantum mechanics by the double solution theory - Louis de BROGLIE'
      http://aflb.ensmp.fr/AFLB-classiques/aflb124p001.pdf

      “When in 1923-1924 I had my first ideas about Wave Mechanics I was looking for a truly concrete physical image, valid for all particles, of the wave and particle coexistence discovered by Albert Einstein in his "Theory of light quanta". I had no doubt whatsoever about the physical reality of waves and particles.”

      “any particle, even isolated, has to be imagined as in continuous “energetic contact” with a hidden medium”

      The hidden medium of de Broglie wave mechanics is the aether. The “energetic contact” is the state of displacement of the aether.

      "For me, the particle, precisely located in space at every instant, forms on the v wave a small region of high energy concentration, which may be likened in a first approximation, to a moving singularity."

      A particle is a moving singularity which has an associated aether displacement wave.

      In a double slit experiment the particle travels a well defined path which takes it through one slit. The associated wave in the aether passes through both. As the aether wave exits the slits it creates wave interference. As the particle exits a single slit the direction it travels is altered by the wave interference. This is the wave piloting the particle of pilot-wave theory. Detecting the particle strongly exiting a single slit destroys the coherence between the particle and its associated wave in the aether.

      If you disagree with the above then explain what occurs physically in nature in a double slit experiment.

      Delete
    10. Hi Mike,

      I see you are new here. You are unlikely to get a coherent answer from MJA. MJA never offers any contributions apart from meaningless deepities about the concept of equality.

      MJA:

      ==, equals, =, ==== - is ===.

      Delete
  28. @Massimo Pigliucci: “This [Multiverse is a great way to solve the fine-tuning problem] is dangerously close to being circular reasoning.”

    Amen!

    But, I think that there is a mentality issue in addition to the circular reasoning. Most of physicists believe that physics is now having only ‘one’ last door not opened. Yet, there is no sign of any linkage between the Standard Model to the rising of life. And, there is no hint of any kind that that link will be found behind this last unopened door. That it, without coming up a way out, physics must accept the defeat and surrender to the Almighty God. Thus, the Nature was declared as un-nature, being only a ‘happenstance’ among the multiverse. In a sense, this (fine-tuning and multiverse) is not exactly a circular reasoning but is a super smart way of weaseling out from the total defeat.


    Of course, this weaseling can be falsified with three points.
    First, for the S-multiverse as a ‘fact’, it has produced a special universe which we are living in. For the S-multiverse-theory, it has failed to describe that ‘fact’, as being unable thus far to find out how ‘this’ universe came about from the S-multiverse fact. That is, the S-multiverse-theory is useless and nonsense.


    Second, there are three types of multiverse.
    1. With different initial and boundary condition for each universe,
    2. With different physics laws in each universe,
    3. With different nature constants in each universe.

    While all three cases should be addressed, I will show only the case 3 (about the nature constants). If the nature constants of ‘this’ universe is not bubble dependent, there is no reason for the nature constants of the other universes to be bubble dependent. The best constant candidate for this discussion should be Alpha as it is the ‘lock’ of three other constants {e (electric charge), c (light speed) and ħ (Planck constant)}. The following equation for Alpha is clearly not bubble dependent.

    Beta = 1/alpha = 64 ( 1 + first order mixing + sum of the higher order mixing)
    = 64 (1 + 1/Cos A(2) + .00065737 + …)
    = 137.0359 …
    A(2) is the Weinberg angle, A(2) = 28.743 degree
    The sum of the higher order mixing = 2(1/48)[(1/64) + (1/2)(1/64)^2 + ...+(1/n)(1/64)^n +...]
    = .00065737 + …

    Its underlying physics is available at http://prebabel.blogspot.com/2013/12/the-great-divide_1900.html . In one word description, it is about ‘sharing’ or mixing. That is, if we view this universe as a ‘pie’, Alpha is the governing rule for how to share this pie.

    On January 5, 2014, Amir Mulic published a new Alpha formula (4π^3+π^2+π). Although Amir Mulic gave it an M-string interpretation, that formula is still purely numerological. Yet, when it is rewritten with the following equation, the physics significance is now all clear.

    Let 2 π = the circumference of a unit disk (with radius = 1) = Pie
    π = half Pie = HPie
    Then, his formula can be written as,
    (1/α) = (1/2) {Pie * [(Pie + 1/Pie)^2 + (HPie – 1/HPie) – ((1/Pie) – 1)^2]} … equation A

    The equation A above is the topological (static) description of the three points above
    (Pie + 1/ Pie), type 1 mixing (division); (Pie + 1/ Pie)^2, the first order mixing
    (HPie – 1/HPie), type 2 mixing (division), the second order mixing
    [(1/Pie) – 1]^2, the ‘remainder’ (indivisible) of the division

    So, equation A = (1/2) Pie * (the first order mixing + the second order mixing - the ‘remainder’ of mixing)

    Thus, Amir Mulic’s formula (4π^3+π^2+π) also is about the ‘pie’ sharing, totally bubble-independent.


    Third, when we show that the laws of ‘this’ universe does give rise to life, then this ‘happenstance’ argument is falsified. The discussion of this is also available in the above link.

    Thus, although by definition that the other universes are unobservable from this universe, the theory of multiverse can still be falsified.

    ReplyDelete
    Replies
    1. Hi Tienzen,

      You say "Amen" to the idea that the multiverse is circular reasoning, then you later recant and say that it isn't, it's clever weaseling instead. Which is it?

      Your numerological account of the fine structure constant seems to me to be arbitrary and post hoc, not to mention inaccurate. The known decimal digits of the inverse of the fine structure constant are 137.03599907. Amir Mulic's formula comes out as 137.036303776. Close, but no cigar.

      As for the first derivation, your own formula for the sum of the higher order mixing gives not 0.00065737... but 0.000656181540339...

      Also, the Weinberg angle is just another magic number. You have offered no derivation of this, and your whole formula depends on it. Without an explanation of the Weinberg angle, all you have done is found a possible mathematical relationship between the Weinberg angle and the fine structure constant. The precise value of the Weinberg angle is not known, but it is approximately 28 degrees +/- a couple of degrees.

      Anyway, taking your value of the Weinberg angle and the correct value for the expansion of the higher order mixing, we get 137.03590239399... again, close but no cigar. Taking instead your value for the expansion of the higher order mixing, we get 137.03597845541... Still no cigar.

      You end each version of your formula with + ...

      What does that ellipsis represent? Is it just to give you wiggle room so as to allow you to derive a number close to the actual value without having to be precise?

      If you look at the Wikipedia page, you'll find an example from James Gilson of a numerological formula that gives a much much more accurate result (though still too inaccurate to work).

      How do you account for the fact that you and Amir Mulic and James Gilson and others have all proposed completely different derivations for the constant? Doesn't this just go to show that a numerological approach will always find multiple ways of getting at just about any number, thereby confirming that it's useless as a predictor of constants?

      And even if you do find a formula that gets it right, why should this constant be determined by your formula and not some other? Haven't you now simply replaced the question "why this constant" with "why this formula?". Why could there not be other universes defined by other formulae and other laws of physics? You have falsified nothing!

      Delete
    2. Thanks for your comment:

      @Disagreeable Me: “You say "Amen" to the idea that the multiverse is circular reasoning, then you later recant and say that it isn't, it's clever weaseling instead. Which is it?”
      I do not see any problem for ‘Amen’ on Prof. Massimo Pigliucci’s great statement while I have some additional opinions.

      @Disagreeable Me: “Also, the Weinberg angle is just another magic number. You have offered no derivation of this, …”
      Very important point. The problem is that you have made a conclusion before doing any research. I have provided a ‘link’ in my last comment. Obviously, you did not review it. Not only Weinberg angle is derived with the same ‘physics’ of Alpha, but also the Cariboo angle. These derivations are available at http://prebabel.blogspot.com/2012/04/alpha-fine-structure-constant-mystery.html .

      The ‘measured’ Alpha depends on the system’s energy and momentum, ranging from 128 (at 90 Gev) to 137+ (at low energy). Only my formula (with Weinberg angle) can produce both numbers, while Mulic’s formula is only a ‘topological’ representation.

      @Disagreeable Me: “You end each version of your formula with + ...”
      No, not for the wiggle room. ‘+’ is very important in this physics, more fundamental than quantum principle. Of course, I have discussed it in detail, but I will not go into it here as you can find it online if you are interested. For a short answer, there is more ‘processes’ in this universe in addition to the ‘static’ (topological) structure of this universe.

      Delete
    3. Hi Tienzen,

      You're right that I missed your derivation of the Weinberg angle, and also that I made some false assumptions and had some confusion of my own. It's not true that I did *no* research, in fact I invested more time in looking into your work than I really had available.

      I don't have time to investigate this further right now but I may come back to you now that I see that I have been too hasty.

      I suspect my final answer is going to be of a similar character, however. If you have managed to derive an approximately correct value for alpha, how do you know that your derivation is the correct one as opposed to all the other possible numerological derivations? Can you justify your deriviation with an a priori argument and if not then how do you know there could not be other universes with other formulae for alpha?

      Delete
    4. This is Prof. Pigliucci’s blog. That is, I should not say too much here. But, for the issue of ‘falsifiability and multiverse’, I would like to beg the permission from the great professor one more time. Then, I will not make any further comment on these issues here anymore.

      First, I made a typo in my last comment. It is ‘Cabibbo’, not ‘Cariboo’.

      @Disagreeable Me: “Can you justify your derivation with an a priori argument and if not then how do you know there could not be other universes with other formulae for alpha?”

      Again, this is a very important point. I will answer it with two points.
      First, my Alpha-formula above (with the Weinberg angle) is based on a new physics ‘concept’ which has two points.
      1. The essence of ‘this’ universe is about two ‘infinities’ (countable and uncountable). Then, both infinities must concretize to form a ‘finite’ material universe. The ‘uncountable-infinity to finite’ concretization process becomes a circle (π or ‘pie’), see "Multiverse bubbles are now all burst by the math of Nature (http://prebabel.blogspot.com/2013/10/multiverse-bubbles-are-now-all-burst-by.html )”. Then, the countable-infinity becomes a trisected ‘angle’ which generates 64 kids, (also see the above link).
      2. Then, this pie (the highest infinity) is ‘divided’ (or shared) by 64 kids (of this ultimate infinity) which consist of two groups; one group (16 kids) takes the energy (dark energy), the other (48 kids) takes the landmass as landlords. See “Pimple Model; BARKED UP THE WRONG TREES (M-THEORY AND SUSY); (http://tienzengong.wordpress.com/2013/09/19/barked-up-the-wrong-trees-m-theory-and-susy/ )” and “DARK ENERGY, MYSTERY NO MORE! (http://tienzengong.wordpress.com/2013/09/25/dark-energy-mystery-no-more/ )”. Thus, the numbers (64, 48 and 24) play the key roles in my Alpha-formula. The whole point is about the ‘dividing’ (or sharing) the pie. If you read the two links above, you will see that the Planck (CMB) data is wholly accounted for by this physics. Then, Neff = 48/16 = 3 (no more, nor less). Of course, the ‘string unification’ (the reproducing the particle zoo of Standard Model) is also completed.

      That is, my Alpha formula is not a numerological construct, and it is absolutely independent on the bubble. Now, Mulic’s formula also describes a ‘pie’-sharing picture. With two witnesses, it passes the requirement in the Jewish law described in Bible.

      Second, if we can show that life of ‘this’ universe is ‘given’ by the physics laws of ‘this’ universe, then it is not rising with ‘happenstance’. That is, the multiverse argument is not ‘needed’. The life has, at least, three attributes.
      a. An information system, that is, it needs a computing device (abacus, counting straws or a Turing computer).
      b. Individuality, needing a ‘four’ color system (such as, A, G, T, C).
      c. Immortality, needing a ‘seven’ color system (such as, A, G, T, C, M(male), F(female), K(kids)).

      In fact, all these ‘three’ are produced by the Alpha-physics. Of course, I should not discuss them here. With these two (first and second), we can comfortably throw away the Simultaneous-multiverse.

      Delete
    5. Hi Tienzen,

      I have had another look, and the promised derivation of the Weinberg angle is not to be found, at least not in detail. It seems to depend on the derivation of a "unit angle" you refer to as A[0] which is only defined on page 36 of your book Super Unified Theory which I don't have access to and do not intend to purchase.

      But even given this angle your formula for deriving the Weinberg angle and the Cabibbo angle seems entirely arbitrary to me.

      Take your formula for the Cabibbo angle for example:

      A(1) = [360 - 24 * A(0)]/24 = 13.5211574853

      Why not something simpler? Why not simply A[0] * 9 = 13.3095826... , which actually gives a result *closer* to the measured Cabibbo angle than your formula?

      If alpha can vary, depending on energy, then that suggests to me that it's not a very good candidate for a constant that ought to be derived from first principles. Any vaguely approximate formula, especially one with a parameter that can be adjusted, as A[0] seems to be for you, can produce a range of appropriate values.

      But I think alpha can be taken to be a precise constant, if the alpha we are talking about is the low-energy alpha, which is known to many decimal places. If you have found a true formula, you ought to be able to predict this value precisely, to an arbitrary number of decimal places. Future more precise physics experiments could therefore potentially falsify your formula, making your formula unambiguously scientific.

      Finally, I am not at all satisfied with your explanation of "+ ...". A link explaining it would be helpful, or else could you at least let me know if you yourself know how to expand this into a concrete value.

      Delete
    6. Hi Tienzen,

      You seem to have constructed an extremely elaborate edifice of theory based on what seem to me to be entirely arbitrary conjectures. Honestly, it is not sufficiently apparent that you are onto anything to make it worthwhile spending months researching the physics and your articles in order to make more sensible comments.

      For instance, I have no idea how you came to chose the special numbers 64, 48 and 24, especially seeing as you use these numbers the context of angles where the more natural unit is radians. 64 degrees is 16pi/45 radians, which is not a particularly round number at all.

      I also have no idea why you think that the three most important properties of life are information, individuality and immortality, or why you associate individuality with the number 4 and immortality with the number 7.

      A problem with your writing is that you seem to assume that a lot of this stuff is self-evident, whereas to someone approaching your work for the first time it is indistinguishable from nonsense.

      Delete
    7. Truly, this is not a place to discuss my opinion. Yet, your questions do relate to the blog article “falsifiability and multiverse”. Thus, I will beg the great professor the kindness one more time.

      Of course, staying on the topic first. In order to falsify multiverse, one more place is very important. Where is the ‘boundary’ of ‘this’ universe? When this universe expands, where does it expand into? If this universe does not bump into the boundaries of the ‘other’ universes, then
      1. The boundary of this universe is ‘independent’ of bubbles, and it should be the same for the other universes.
      2. The other universes are irrelevant to this universe, and vice versa. That is, the multiverse or not is no issue at all.
      For the detailed discussion of this is available at http://prebabel.blogspot.com/2013/11/why-does-dark-energy-make-universe.html .

      Now, let me answer your critiques.
      “But even given this angle your formula for deriving the Weinberg angle and the Cabibbo angle seems entirely arbitrary to me. … If alpha can vary, depending on energy, then that suggests to me that it's not a very good candidate for a constant that ought to be derived from first principles. … For instance, I have no idea how you came to chose the special numbers 64, 48 and 24, ... to be entirely arbitrary conjectures.”

      Alpha varies by ‘measurement’, not by definition. In the Alpha-physics, Alpha is much, much more than a ‘coupling’ constant. It is a “lock” which locks the three most ‘fundamental’ nature constants {e (electric charge), c (light speed) and ħ (Planck constant)}. After these nature constants are firmly ‘locked’, the universe is allowed to roam free. The following concept is not an arbitrary conjecture although it could be viewed as a conjecture.
      a. Nature’ essence: two infinities.
      b. The creation of the material universe: infinities concretizations.
      c. The structure of this universe: the sharing of this concretized pie.

      The way of sharing (the unit angle and the numbers of 64, 48 and 24) is described in
      A. http://prebabel.blogspot.com/2012/04/48-exact-number-for-number-of.html
      B. http://www.prequark.org/think04.htm#A09

      “If you have found a true formula, you ought to be able to predict this value precisely, to an arbitrary number of decimal places.”
      My Alpha equation can give any number from 128+ to 137+ to any arbitrary number of decimal places. What do you talking about?

      “Finally, I am not at all satisfied with your explanation of "+ ...". “
      This is truly ‘the’ issue, and I cannot go into it here. You can begin with http://www.prequark.org/Fermat.htm

      “.. whereas to someone approaching your work for the first time it is indistinguishable from nonsense.”
      Indeed, so far it is. It took me 20 years to come up my Alpha formula. If I saw such a ‘numerological’ formula before I did my own, I will definitely not see it as nonsense even if it were purely ‘numerological’.

      Delete
    8. As far as I can tell Massimo is pretty tolerant of digressions, so I wouldn't worry about it.This comment thread is mostly dead anyway.

      >Where is the ‘boundary’ of ‘this’ universe? When this universe expands, where does it expand into?<

      There are many different kinds of multiverse. The explanation of this question depends on what you mean. This paper outlines my view. I'm agnostic on mutliverse level 2, but I definitely believe in levels 1 and 4 and am pretty confident of 3.

      http://space.mit.edu/home/tegmark/multiverse.pdf

      But no, I don't imagine that space is expanding "into" anything. That presupposes some kind of external space. I even suspect that space is infinite in extent, and its expansion does not so much represent an increase in volume as a reduction in density as everything flies apart from everything else.

      I don't have time to digest your links right now but may come back to them later.

      >My Alpha equation can give any number from 128+ to 137+ to any arbitrary number of decimal places. What do you talking about?<

      There is a precisely measured value for 1/alpha of 137.03599907... This represents the value of alpha at low energies. If your derivation is correct, you should be able to precisely calculate the lower bound for alpha, corresponding to this number. Similarly, you should be able to derive the upper bound for alpha, corresponding to 128. We can't measure the upper bound accurately yet, but you should be able to predict it.

      >If I saw such a ‘numerological’ formula before I did my own, I will definitely not see it as nonsense even if it were purely ‘numerological’.<

      I'm not saying it is nonsense, I'm saying it is indistinguishable from nonsense to me and I suspect anyone else who reads it. It's a tangled mess of links to pages on various different websites and books, and prima facie it seems implausible. Even if you are right, you cannot expect anyone to take you seriously with the information presented in the way it is. Come up with some evidence that you are on the right track first, to make it worthwhile for someone to invest the time necessary to understand you. Make a falsifiable prediction that passes a test. For example, accurately predict the lower bound for alpha.

      Delete
  29. Max Tegmark pushes back against his 'multiverse theory' skeptics ("Can't be falsified!") in a SciAm blog post yesterday:

    Are Parallel Universes Unscientific Nonsense? Insider Tips for Criticizing the Multiverse

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    Replies
    1. @Philip Thrift:

      Thanks for link.

      Max Tegmark’s position is quite fair with his statement “If any of the attacks succeed, the corresponding multiverse evidence is discredited. Conversely, if all the attacks fail, then we’ll be forced to take parallel universes more seriously whether we like them or not – such are the rules of science.”

      But, I think that his argument can still confuse people as some theories being discussed are quite complicated and are not truly understood by the laypersons. Thus, I would like to clarify them here. He really talked about two issues here
      1. Four levels of multiverse.
      2. Is space a continuum? Most of layperson might misses this crucial point.

      There is nothing wrong with his four level description, but it can be very misleading. Thus, I will try to use a three categories description.
      a. With different initial and boundary condition for each universe,
      b. With different physics laws in each universe,
      c. With different nature constants in each universe.

      This new classification is, in fact, more encompassing than the four level one, as it encompasses the cycling universes (with the same physics laws and nature constants but with different initial and boundary conditions). Then, for the level I, I will not see it as a different universe if it simply has an “event horizon”. If it is ‘infinite’ in size, then it could be viewed as a kind of multiverse as the current physics laws (especially the Standard Model) are unable to describe such an infinite size universe. So, we can reduce this issue one step further.
      A. C-multiverse (cycling universes, with different initial and boundary condition but with the same physics laws and nature constants): it is the consequence of Alpha-physics, and the ‘inflation’ is the accrued result of all the previous universes before ‘this’ big bang. That is, I am the proponent of this C-multiverse.
      B. S-multiverse (simultaneous universes or parallel universes, with different physics laws and nature constants): although by definition, this S-multiverse is unobservable from ‘this’ universe, it can still be falsified with four points.


      In fact, Max Tegmark has mentioned one very important pathway, “… A third line of attack is to give a compelling explanation for the observed fine-tuning of physical constants that doesn’t rely on a Level II multiverse.” My previous comments in this thread is about this. Yet, I would like to summarize it in a better understandable way.

      First, S-multiverse ‘theory’ is a ‘failed’ theory, as it is unable to produce the known (this) universe from it thus far.

      Second, its argument (the only explanation for the rising of ‘life’, etc.) is useless, not needed.

      Third, we need one example to show that its argument is wrong. That is, the nature constants of ‘this’ universe are not bubble-dependent.

      Fourth, it has no relevancy to ‘this’ universe, as it has no impact of any kind on this universe since the boundary of this universe is not in contact with any other S-multiverses.

      Is S-multiverse already falsified? This is not truly important. But, the four points above show a clear pathway of how to falsify the S-multiverse.

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