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The string theory hype machine will never die

math.columbia.edu

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Re: The string theory hype machine will never die

#41

Post by XorNot »

slashdave wrote: post #28
qarl wrote: post #7

Earlier quoted context omitted.

Heh... as someone on the outside, I feel the need to ask: Has it been rigorously shown that it can never be tested? Or is that your prediction?

Test which version? Part of the problem is that string theory is a meta theory. There will always be ways to escape any negative experimental result.

String theory isn't a theory it's a family of related theories sharing some common mathematical tools.

People talk about this as though it's an attempt at deception, whereas two people notionally working in string theory could in fact be proposing highly incompatible models which would be conclusively ruled out (and a lot of them have been in so far as that can be done - i.e. experimentation has put tight bounds on their possible parameters).

Re: The string theory hype machine will never die

#42

Post by catigula »

isolli wrote: post #6

It reminds of this quote from Roger Penrose's book, Fashion, Faith, and Fantasy in the New Physics of the Universe: “My nervousness was perhaps at its greatest because the illustrative area that I had elected to discuss, namely string theory and some of its various descendants, had been developed to its heights in Princeton probably more than anywhere else in the world.” “Moreover, that subject is a distinctly techni…

He's just saying he doesn't want to be eviscerated by Ed Witten, which is a pretty commonly shared sentiment in the community.

Re: The string theory hype machine will never die

#44

Post by XorNot »

AnimalMuppet wrote: post #16
ekjhgkejhgk wrote: post #10

Earlier quoted context omitted.

One day when I'm not being lazy I might publish a point by point refutation of the usual nonsense anti-string theory memes. Until then, here's what I said on this point 25 days ago, specifically the first paragraph starting with "like another commenter". https://news.ycombinator.com/item?id=46336655

OK, but if there are no predictions that we can test for several generations, how do you tell the difference between science and science-sounding nonsense?

It might be worth considering what you think research in a field like mathematics actually entails when asking such questions.

Because you can write a lot of mathematics with no practical applications for generations (then whoops: number theory and cryptography!)

Re: The string theory hype machine will never die

#45

Post by prof-dr-ir »

raffael_de wrote: post #34
prof-dr-ir wrote: post #14

Among theoretical physicists there is little doubt that Edward Witten is currently the greatest living theoretical physicist. Here is an interview with him from a few weeks ago: https://www.youtube.com/watch?v=sAbP0magTVY I think it is a great watch for anyone with an interest in the field.

eric weinstein said that witten is the dark lord of string theory; scotching any advance in theoretical physics.

Yes, and RFK Jr. says certain vaccines have never worked.

I guess what I want to convey is how sad your comment makes me. What went wrong that makes you, and anyone really, trust that man's opinion on physics?

Here is a cynical but overall rather accurate takedown of Mr. Weinstein:

https://www.youtube.com/watch?v=DUr4Tb8uy-Q

Re: The string theory hype machine will never die

#46

Post by sega_sai »

mkw5053 wrote: post #8

It feels like Woit is just being a hater at this point. In a meritocracy, talent and funding gravitate toward the most promising options. If string theory took up a large proportion of people and resources, it’s because it solved technical problems no other framework could. Even if it hasn't yielded a Theory of Everything, the fact that its toolkit is now solving problems in other fields suggests the program has led…

The problem is the 'most promising option' is affected by hype and loud voices. Many of the string theory crowds made predictions that did not pan out at all and still did not acknowledge their mistakes. I think that's the problem. Sure there was a lot beautiful mathematics discovered, and it can be used in some other fields, but the acknowledgement of failure of string theory is needed, rather than trying to point here or there where some of the tools from ST could be used. (I am a physicist, but nowhere near the strings theory)

Re: The string theory hype machine will never die

#47

Post by bluGill »

XorNot wrote: post #44
AnimalMuppet wrote: post #16

Earlier quoted context omitted.

OK, but if there are no predictions that we can test for several generations, how do you tell the difference between science and science-sounding nonsense?

It might be worth considering what you think research in a field like mathematics actually entails when asking such questions. Because you can write a lot of mathematics with no practical applications for generations (then whoops: number theory and cryptography!)

Mathematics often does apply to the real world, but that isn't the goal. Physics is about the study of the real universe. If you want to call string theory a branch of mathematics I'd be fine with it, but they keep trying to claim they are physicists and that puts a higher bar on what we expect from them.

Of course physicists sometimes do make wrong predictions and it can take some time to figure out the hypothesis is wrong. However the goal is always to make something they can test to prove the hypothesis holds, which string theory has so far failed to do.

Re: The string theory hype machine will never die

#48

Post by asdff »

Animats wrote: post #20
rbanffy wrote: post #2

All it needs is an experiment that can test it.

High-energy physics is kind of stuck on that. Most of the interesting questions involve energies or distances way beyond what's reachable by experiment today. Meanwhile, there's interesting experimental action in low-energy physics, down near absolute zero. Many of the weirder predictions of quantum mechanics have now been observed directly. Look at the list of Nobel laureates in physics since 1990. A big fraction of…

Kind of interesting to think about how the scale (range or magnitude) in which we are able to detect something has such striking implications for the model that gets developed based on these findings.

Even when we are able to operate at higher resolution sometimes the model makers still operate on their own scales. For example, I believe political science and economics ought to be studied from a biological perspective if they are to be fully understood, since gene by environment interaction determines so much. However, there seems to be little interest among political scientists and economists to study the nitty gritty of molecular and population genetics, and little interest among the molecular and population geneticists to study political science and economic theory. And because of this, seems to me such models will always fall short compared to models that operated on a perhaps more appropriate scale of inputs.

Re: The string theory hype machine will never die

#49

Post by superjan »

torginus wrote: post #31

Unfortunately my understanding of physics stops at general relativity and quantum mechnics (which I did study both at uni, with some mathematical framework of understanding). How would I advance from this point, what should I read to get a grip on string theory, including the concepts and maths involved? Could you recommend some resources? Like why did they come up with the concepts they came up with, how does that h…

I would argue that you don’t need to learn string theory as it currently does not predict anything we can realistically observe (as you need energies that occurred only at the big bang). If string theory is correct we could observe a “supersymmetric” twin of all known particles, however we haven’t seen these, and they could exist even if string theory is false.

String theory aims to explain all physics as manifestations of a mathematical concept best understood as a vibrating string.

Initially, the hope was that string theory could predict the particle masses we observe, but that hasn’t worked as it turns out there were many different predictions possible. String theory has also struggled to develop a version of the theory that does not contradict known properties of our actual universe.

Loop quantum gravity is not equivalent to string theory, except that it also tries to unify gravity and quantum physics.

As things stand, string theory is not falsifiable, while that is the case, you could argue it does not count as physics.

But, by multiple accounts, it is interesting math, which can be worth doing for its own sake, and it’s happened often enough that interesting math turned out to be useful somewhere. Just not for explaining physics.

Re: The string theory hype machine will never die

#50

Post by jcranmer »

daxfohl wrote: post #13

Hasn't it just been subsumed by AdS/CFT now? IIUC that's a layer of abstraction but still primarily string theory under the hood. That's still an active area isn't it? Or is that dying too?

I've heard AdS/CFT described as a correlation between something that doesn't describe our universe (which is maybe de-Sitter, but definitely not anti-de-Sitter space) and something else that doesn't describe our universe (the fundamental forces are not describable with a conformal field theory).
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