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String theory has completely dominated the field of theoretical high energy physics for decades. There have been some notable contrarians, e.g., Smolin and Woit with their books. But those haven't changed the fact that it has been very hard to get a faculty position in theoretical hep for decades without being a string theorist. It is only the last few years that has changed. In other words, it's not a biased view that string theory has completely dominated the field for more than 30 years.

Btw, the reason we aren't reading Feynman's take is that he died in 1988, not that he's too busy doing physics. He was very successful in doing both high quality physics and expanding his popular reach.

That's just not true. Look at the statistics for hiring faculty in theoretical high energy physics [1]. String theory was never more than half, and usually much less than that. (It is true, though, that for a while they had a near monopoly on pop physics. But that's totally different from physics.)

[1] http://www.particle.physics.ucdavis.edu/rumor/doku.php?id=st...

His statement can be true if you restrict it to "quantum gravity" jobs (of which string theory is one of many approaches, abeit the overwhelmingly most popular one). The other jobs you're talking about just don't try to answer the questions that string theory purports to addresses.

Despite its drawbacks string theory may actually be our best theory of quantum gravity, perhaps even enough to justify its hiring ratio relative to other quantum gravity theories. Maybe string theory has been treated in a balanced way all along.

Maybe, or maybe not. My personal opinion is that even thirty years ago it seemed stupid to bet almost all resources on a theory that was too complex for anyone to even produce any testable predictions. And I think it is even more stupid now, when the main result of the theory seems to be that it's not possible to use it for any prediction (10^500 possible universes, it's not possible to say which one).

Unless you mean "almost all PBS physics documentary budget dollars," I don't think almost all resources were bet on it.

From the money available for fundamental questions like quantum gravity and beyond standard model physics, almost all resources were bet on it.

It's kind of cute how some people now are trying to rewrite history when it is more and more obvious that it was a dead end.

There has to be a couple of orders of magnitude difference between "funders thought it was the best bet for quantum gravity," and "it was all physicists did for thirty years, full stop."

I, nor anyone else I saw (I haven't read all comments), have claimed that that was what physics did for thirty years. If you read my comments you'll see that I have been quite careful to qualify my statements when it hasn't been blaringly obvious from context.

That is like understanding programming jobs as embedded Erlang. The thing is, that journalists really like to write about quantum gravity, but almost all theoretical physicist work on something else. (Roughly in the same sense that most lawyers don't work at the White House.)

I'm well aware of the distribution of theory jobs and what journalists like to write about. The point is that phenomenologists (and relativists, etc.) are necessary regardless of how dominant strings is. "All theory jobs" was simply a mistaken choice of category.

Im a physicist, and whilst Im an experimentalist, I work in the same departments as theorists and I don't know a single string theorist. I heard of one, once. A friend od a friend, but I never met them. Most high energy physicists seem to be working on supersymmetry.

I've been hearing good things about the super-asymmetry research from CalTech that was confirmed by Fermilab.

A good rule of thumb is that if you hear ”confirmed” and ”symmetry” together, the conversation isn’t about supersymmetry.

In this case, I believe that when someone talks about super asymmetry they're probably referencing this:

https://www.livescience.com/64557-the-big-bang-theory-super-...

So one person got the joke at least.

But we've already found half the particles!

I am not a physicist, but I listen to a lot of technical lectures from the institute of advanced study and other universities that post their colloquia on youtube, and the impression I've gotten is that string theory has pretty much fused with quantum field theory. A lot of the people in the string theory discussions identify themselves simply as field theorists, with string theories being just another set of concepts in their model-building tool box.

> [Horgan] puts all his energy into expanding his popular reach.

I would not say 'all', but this bet fits the claim. If he had lost, his position as a prescient naysayer would be gone anyway, while a win could be used to boost it, even though, as it happens, no decisive case against string theory (or for an alternative) has emerged in the interim. In a sense, this bet is a columnist's hedge against there being no news.

For any counterparty, however, a win would have been completely overshadowed by the science itself. A person might be happy to accept the bet as a form of harmless entertainment, but for Horgan, it was more than that.

The advantage of being a mathematician is that the unifying theories for QM and GR just that, mathematical techniques to unify QM and GR. Unfortunatly, if you are a physicist, I assume your grants at some point will have the words "predictions" or "experiments" in them.

But for someone focused on mathematics, string theory, quantum loop gravity (if that is what it's called) and all the others become tools and objects of study on their own that have a unique perspective to offer in their own right. Whether you study one or the other then becomes a personality inspired preference. Just because I don't study number theory, doesn't by default scorn the field (or perhaps I just can't do number theory).

In quite a few countries, string theorists (and usually GR people too) are far more likely to be in mathematics departments than in physics. Pretty much for the reasons you describe -- GR was seen in the 60s as an exotic mathematical playground, not quite real physics.

This is also true of QM (not just because of QM computational sciences). My MSc thesis has application to quantum mechanics. I wrote a short summary of the generalisation that I made here [1], which generalises what the Nijmegen group calls quotient comprehension chains to sets. The authors of the latter QC-chains did not seem much interested when I emailed them.

In any case, ideally the framework should touch on geometry eventually as well, but I am not aware of concrete ways to do it. Toposes are considered geometric, but I don't know whether geometric in the sense of GR. The eventual or at least, hopeful, end point is something like [2] where your mathematical framework should ideally in the language of categorical or functorial duality express physical dualities. I don't know how to get to GR, as I say, and should read maybe this [3] but there are many ways to get to QM. One example is through entropy: the generalised abstract set subobjects are partitions and partitions encode entropy through "distinctions", i.e, elements in separate equivalence classes of the partition. The category of sets itself is a model for QM theories via it's inspiration for (symmetric) monoidal categories so perhaps one would want to express in the self-dual language that as well. It's one thing to point to multiple uses of category theory in physics, but it is another to keep track of it in your personal, internal intuition strategy.

[1] https://arxiv.org/abs/1808.01350

[2] https://en.wikipedia.org/wiki/AdS/CFT_correspondence

[3] https://ncatlab.org/nlab/show/duality+in+string+theory

I recently got my hands on a book about the career of a esteemed professor and his students. One of the life lessons of one of his students was: "If you want to be called a mathematician prepare to be funded like a mathematician"

Pure theoretical physicist might be in a comparable budget, but I think it is true that the lower expectations on math research is partly due to how cheap it is to fund.

What was the book?

"would have trouble making predictions. Physicists have made this criticism since the beginning."

You can go one step further. If you regard string theory as an attempt to answer questions about quantum gravity, then this criticism applies to the whole question, not just to any particular school of thought about answering it. This was known since approximately the time when physicists first had access to Planck's constant, Newton's constant, and a spare envelope to write on.

But, as you say, this is far from all that people who get called string theorists work on. A great pile of mathematical tools have been developed, to the point where deliberate ignorance of all of them would be a very strange position. Not for all fields of theory, obviously, but for quite a few.

Well I’m not reading Feynman’s take because he is dead right now.

I like the "right now" there. Like, fingers crossed, that could change...

It's not impossible, just isn't very probable.

Obligatory xkcd: https://xkcd.com/397/

All string theorists are theoretical physicists, noz all theoretical physicists are string theorists. Many string theorists contribute in other fields.

How is holography any more concrete than string theory? It is just as untestable.

You use it as a tool to compute what happens in real things, such as quark-gluon plasma or certain condensed matter systems.

You should be careful to not overstate it's rigorous application to QGP or condensed matter systems though.

For example, for QGP, holography can paint a nice picture, but we don't know a holographic dual for Nc=3 QCD.

We must not be discussing the same thing.

EDIT: yup, I am not knowledgable enough to be in this conversation.

It should really be called String Hypothesis. Theories in science are generally for something that's near 100% proven.

The difference between hypotheses and theories isn't about whether one is more likely true, they are different kinds of structures with different roles.

A hypothesis is ideally 'atomic': it's making a single assertion that should be falsifiable by experiment.

A theory provides a specific way of modeling the elements of some field of study, and how those elements interact with one another.

It should be structured in such a way that it can describe the components of any experiment that might be set up to confirm/reject a hypothesis in this field.

And once an experiment is described in the terms of some theory, the theory should provide a systematic way of calculating what the result of the experiment should be.

That's where the connection between hypotheses and theory comes in: actually conducting experiments assigns either Acceptance or Rejection to a set of hypothesis; ideally, the theory assigns the same Accept/Reject values to the same hypotheses in its predictions (this is probably never 100% the case in practice though—esp. not in an active field of study).

The structure of String Theory is much closer to theory than hypothesis. (It may have limitations in how much it models physical 'experiments,' but it's at least much more of a 'system description' than an atomic assertion.)

That's a trope made up on the spot to defend Darwinism from "it's just a theory/teach the controversy".

Whether in science or police work, etc. a theory is a holistic framework, while a hypothesis is truth-valued.

We should also complicate this idea that something can be 100% proven, but baby steps.

Physicists and philosophers of science give those terms different meanings. E.g. what a philosopher of science would call a theory is called model by physicists. What physicists call a theory is more a broad framework in which more concrete models can be build.

From the view of a philosopher of science string theory isn’t even a hypothesis as a hypothesis needs to be testable