We are taking on fundamental physics! Our guest on the next episode of the Rationally Speaking podcast is Peter Woit, a physicist in the Department of Mathematics at Columbia University and author of Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law. We will discuss the apparently peculiar state of theoretical physics (see also Lee Smolin’s The Trouble with Physics: The Rise of String Theory, The Fall of a Science, and What Comes Next) and the rather startling possibility that superstring theory — the best candidate in decades as the elusive “theory of everything” — may actually have been a colossal dead end for the physics community.
In the process, we will explore with Peter the meaning of theory in science, and what is the connection between theory, observation and experiment. As it turns out, superstring theory has not been able to make any empirically testable predictions, which supports the argument that perhaps it isn’t — as Peter puts it — “even wrong,” meaning that it just isn’t science. Then again, the same has been true for other scientific theories in the past, which have been kept alive for years on the grounds that they were appealing or made sense, and were then shown to in fact be correct (the Copernican theory being just one example).
Well this is tangential but I have to ask.
ReplyDeleteDoes the scientific community and more often the public at large, mistake coherency for universality?
Wanted to point out, in case, that "not even wrong" is a W. E. Paulis' answer to a request for an opinion about a paper. Deadly.Dr Woit wrote about it in the preface of his book, highlighting the meanings associated with it. Built on facts weblog also talked about it. Dr Pauli and Peter Lorre (the actor), at one stage of their careers, resemble each other.
ReplyDeleteWoit has a powerful argument. No one refutes that string theory has to date made testable predictions. His problem is that he has failed to date to make an argument as to why a unified theory should be abandoned. And, if we're not going to abandon the idea, then what is the alternative to string theory?
ReplyDeleteI'm good either way, but make an argument, either way.
If the consensus is currently to search for a unified explanation then string theory has at least consistent mathematics behind it. If a unified theory should be abandoned, fine let's start working on where the boundaries are.
I don't know if you've read Woit's book (if you haven't, I'd recommend it; it's good).
ReplyDeleteIn it, part of what he argues is that string theory has succeeded in monopolizing most of the resources in theoretical physics, starving other alternatives. I think the one he mentions is loop quantum gravity, but I seem to recall Smolin mentioning others in his book (my knowledge of the subject is restricted to popular science books, so unfortunately I can't name or explain them).
So there are alternatives, and a few people working on them. If you haven't heard of them, well, that's probably because string theory is significantly more popular, and has far more people working on it (by some accounts, simply because it's difficult to get a position working on anything but string theory), and despite that fact, there are no testable predictions to show for it.
String theory isn't the only game in town; it's just the most popular, and for apparently social, rather than scientific reasons.
And that's not even considering what people might have come up with if there weren't so much pressure for them to just work on string theory. If string theory is a dead end, then saying "it's mathematically consistent" is of no value. You may not be able to find the right theory by continuing to polish it. Woit and Smolin not personally knowing what the right direction is isn't an excuse to dismiss their arguments that we are directing everyone in what certainly appears to be the wrong direction, and we would be better served having more of them exploring. That's a variation of the old "unless you have an explanation of X, all the problems you've pointed out in my explanation don't matter. (Therefore, Calvinism. :))"
At least, that's what I understand the thrust of Woit and Smolin's arguments to be.
There is a popular notion that theoretical physics can be included in the domain of "science".
ReplyDeleteIn actuality, it is more aptly described as "science fiction" that happens to be predominantly written in the very simple language of mathematics rather than natural language.
That is why string theory, in common with quantum loop gravity and the various other (usually mutually exclusive) TOEs, are indeed "not even wrong"
Any of these fictional models that might happen to be testable have, of course, the opportunity to one day become "science" and become part of physical theory within that domain.
They have value but are not science.
There is thus an important distinction to be made between theoretical physics and physical theory.
The former is mathematical science fiction.
The latter comprising our best understanding of the ways of our universe within an evidential framework.