5 ms·

It's difficult for a non-specialist to place this article in a broader historical context. I thought string theory was by now more or less considered a dead-end

by isolli 8y ago

It's difficult for a non-specialist to place this article in a broader historical context. I thought string theory was by now more or less considered a dead-end, so I wonder if this article is an attempt to revive it, or the first sign that it may actually go somewhere after all. Maybe someone knowledgeable can weigh in?

dkural 8y ago
It is still considered a dead-end. This is a puff / PR piece going over well known old arguments to promote it to the lay public.
- MockObject 8y ago
  Does that mean there's nothing promising anymore in AdS/CFT correspondence?
  - Pharmakon 8y ago
    It’s interesting mathematically, but we don’t live in an AdS universe so there’s that. Recently there’s been some progress extending the notion fromthe AdS toy model to a dS toy model, but the degree to which any of that applies to anything real’s questionable. “Interesting, but with no indication of a valid physical interpretation in the universe” is probably the best way to sum up the world of string theory. The other big problem is that a lot of what made it seem natural and elegant has been progressively ruled out, so you’re left with far less simple and elegant versions which could apply to the universe. At that point you have to ask what the appeal is, you know? It’s not unlike the problems with Inflationary cosmology. Originally it was a simple way to resolve outstanding issues of homogeneity and isotropy of the observable universe. That was based on a model with a very natural PE curve, which has been ruled out. Now we’re left with a “curve” every bit as contrived as simply saying “because” in reference to the underlying questions. In both cases, M-Theiry and Inflation, they persist because of huge investments of time and energy into them, and because as yet no strong competitors have emerged.
peteradio 8y ago
Who is saying string theory is dead? Is it the theorists themselves or are they discounted due to conflict of interest so we only get to hear pop sci articles from people who can't do integrals let alone understand SS beyond shit analogies.
- ivalm 8y ago
  A lot of high energy theorists themselves are discouraged. Basically almost all theorists outside of high energy/cosmology are VERY discouraged about the prospect of superstrings.
orbifold 8y ago
I've worked on string theory briefly (published one paper that got a respectable number of citations). It is not considered a dead end by people working on it obviously. Many of the best people in theoretical physics with Edward Witten being the most prominent example have been working on it for ~40+ years now. None of the public detractors have nearly the same stature that Witten has. Of course this is basically an argument by authority and there is a chance that once titans like Witten leave the playing field the following generations will lose more and more influence. I think there is a fair bit of criticism of String Theory among very good people that is not voiced publicly because there would be no point to it, they have nothing to gain. In many ways it is the "Only Game in Town" (literal quote from my supervisor), just doing high-energy particle phenomenology is not that much more exciting. String theory has already led to a number of very high profile successes in mathematics (Perelman's Proof of the Poincare Conjecture, Monstrous Moonshine etc.), so it is not like the techniques that have been developed are totally useless.
- osheamonn 8y ago
  What does string theory have to do with the proof of the Poincare conjecture? This is the first I've heard that there was any link there.
  - orbifold 8y ago
    The starting point of Perelman's proof is the observation that (a modified version of) the Ricci flow is a gradient flow. The connection to 2d non-linear sigma models is briefly discussed in section 2 of the introduction in https://arxiv.org/pdf/math/0211159.pdf https://arxiv.org/pdf/math/0211159.pdf and section 1.4*. The overall intuition is that string theory captures the geometry of the back ground Riemannian manifold.
- goatlover 8y ago
  > In many ways it is the "Only Game in Town" (literal quote from my supervisor), Aren't there a few alternatives such as Quantum Loop Gravity?
  - 8y ago

by isolli 8y ago

dkural 8y ago

It is still considered a dead-end. This is a puff / PR piece going over well known old arguments to promote it to the lay public.

MockObject 8y ago
Does that mean there's nothing promising anymore in AdS/CFT correspondence?
- Pharmakon 8y ago
  It’s interesting mathematically, but we don’t live in an AdS universe so there’s that. Recently there’s been some progress extending the notion fromthe AdS toy model to a dS toy model, but the degree to which any of that applies to anything real’s questionable. “Interesting, but with no indication of a valid physical interpretation in the universe” is probably the best way to sum up the world of string theory. The other big problem is that a lot of what made it seem natural and elegant has been progressively ruled out, so you’re left with far less simple and elegant versions which could apply to the universe. At that point you have to ask what the appeal is, you know? It’s not unlike the problems with Inflationary cosmology. Originally it was a simple way to resolve outstanding issues of homogeneity and isotropy of the observable universe. That was based on a model with a very natural PE curve, which has been ruled out. Now we’re left with a “curve” every bit as contrived as simply saying “because” in reference to the underlying questions. In both cases, M-Theiry and Inflation, they persist because of huge investments of time and energy into them, and because as yet no strong competitors have emerged.

peteradio 8y ago

Who is saying string theory is dead? Is it the theorists themselves or are they discounted due to conflict of interest so we only get to hear pop sci articles from people who can't do integrals let alone understand SS beyond shit analogies.

ivalm 8y ago
A lot of high energy theorists themselves are discouraged. Basically almost all theorists outside of high energy/cosmology are VERY discouraged about the prospect of superstrings.

orbifold 8y ago

I've worked on string theory briefly (published one paper that got a respectable number of citations). It is not considered a dead end by people working on it obviously. Many of the best people in theoretical physics with Edward Witten being the most prominent example have been working on it for ~40+ years now. None of the public detractors have nearly the same stature that Witten has. Of course this is basically an argument by authority and there is a chance that once titans like Witten leave the playing field the following generations will lose more and more influence. I think there is a fair bit of criticism of String Theory among very good people that is not voiced publicly because there would be no point to it, they have nothing to gain. In many ways it is the "Only Game in Town" (literal quote from my supervisor), just doing high-energy particle phenomenology is not that much more exciting. String theory has already led to a number of very high profile successes in mathematics (Perelman's Proof of the Poincare Conjecture, Monstrous Moonshine etc.), so it is not like the techniques that have been developed are totally useless.

osheamonn 8y ago
What does string theory have to do with the proof of the Poincare conjecture? This is the first I've heard that there was any link there.
- orbifold 8y ago
  The starting point of Perelman's proof is the observation that (a modified version of) the Ricci flow is a gradient flow. The connection to 2d non-linear sigma models is briefly discussed in section 2 of the introduction in https://arxiv.org/pdf/math/0211159.pdf https://arxiv.org/pdf/math/0211159.pdf and section 1.4*. The overall intuition is that string theory captures the geometry of the back ground Riemannian manifold.
goatlover 8y ago
> In many ways it is the "Only Game in Town" (literal quote from my supervisor), Aren't there a few alternatives such as Quantum Loop Gravity?
- 8y ago