Eric Weinstein's Geometric Unity theory

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Summary:

geometric unity

Main Question or Discussion Point

Eric Weinstein finally released a video of his 2013 Oxford talk on "geometric unity". There are many fans and skeptics out there, looking in vain for a genuinely informed assessment of the idea.

I admit that so far I have only skimmed the transcript of the video, being very pressed for attention and time these days. But I come away with the impression of a four-manifold, with some kind of a connection and some kind of fermion bundle, and then mostly he counts degrees of freedom and hopes that this will give the fermions and gauge fields of the standard model.

But one thing that caught my attention, is his remark in the 2020 introduction, at 28 minutes, that Witten's 1994 quantum-field construction of Donaldson theory (a branch of pure math) could also be obtained from Weinstein's starting point; and that Weinstein's model could also have given rise to the Seiberg-Witten equations.

Not only are those rather strong claims, but they might actually help us arrive at a more nuanced grasp of what Weinstein's idea is. As you may read here, Witten obtained Donaldson theory by starting with an N=2 field theory, then "topologically twisting" it to obtain a topological QFT; and Seiberg-Witten equations may be obtained in a different limit. Weinstein doesn't employ supersymmetry, so one has to wonder what he's thinking, but maybe this can still help us zero in on what his idea is.
 

Answers and Replies

  • #2
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In addition, to the video can you provide reference(s) for the relevant paper(s) that the video is based upon?
 
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George Jones
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In addition, to the video can you provide reference(s) for the relevant paper(s) that the video is based upon?
As far as I can tell, there are no relevant papers. From Wikipedia
https://en.wikipedia.org/wiki/Eric_Weinstein

"In May 2013, Weinstein gave a colloquium talk, Geometric Unity, promoted by Marcus du Sautoy as a potential unified theory of physics.[9][10] His unpublished theory includes an "observerse," a 14-dimensional space, and predictions for undiscovered particles which he stated could account for dark matter. Joseph Conlon of the University of Oxford stated that some of these particles, if they existed, would already have been detected in existing accelerators such as the Large Hadron Collider.[11]

Few physicists attended and no preprint, paper, or equations were published.[12] Weinstein's ideas were not widely debated. The few that did engage expressed skepticism.[11][13] They were unable to debate more intensely due to the fact that there was no published paper.[14]"

I would like to be contradicted, but I cannot see that the situation has changed since 2013.
 
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  • #4
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This is a tough call, we can debate peer-reviewed papers but not a video of ideas without clarity or depth.
 
  • #5
klotza
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George Jones, the only way the situation changed is that he (or someone) put his talk onto youtube, so now people can watch. The situation had evolved from "we can't really evaluate his theory based on a one paragraph abstract" to "we can't really evaluate his theory just based on his talk." There is still no white paper, or even a website where he lines it out, so there's not much to be gotten out of the whole thing.
 
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In addition, to the video can you provide reference(s) for the relevant paper(s) that the video is based upon?
Weinstein says the paper is forthcoming.
He has recently caught my eye when addressing the geometry of spinors in an interview with Penrose, and then alluding that the very foundational basis of twistor theory is also consistent with his new theory; much of what he said didn't just seem to be news to me, it seemed like news to Penrose as well.

Weinstein extensively quotes the works of geometers and topologists; all in all he sounds closest to John Baez, but then from a Woit/Smolin perspective. In any case, I will try to review Weinstein's work here, given of course that time allows it.
 
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Transcript of the video.

There are some motivating remarks at 50 minutes, in which Einstein gravity, Yang-Mills theory, and a Dirac equation are described as the three ingredients of known physics, whose inconsistencies and tensions are to be examined, in order to find a deeper common framework. This part might be of interest even for people who don't care about Weinstein's theory.

His own answer seems to be, define a kind of connection and spin connection on the 14-dimensional space of metrics of a 4-manifold, which can then be projected onto the 4-manifold itself, in order to obtain the phenomenological fields.

He likes the (well-known) idea of getting a generation from a 16-dimensional spinor; but says he gets only two, not three, and speculates outlandishly about how the appearance of a third generation is created. But actually the particle-physics part is the handwaving-est part and it wouldn't surprise me if he changed his mind about how it works.
 
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and it wouldn't surprise me if he changed his mind about how it works
Given the vagueness of his presentation, I would say it's not clear that even Weinstein really knows how it works!

While I'm not a physicist, I recall the controversy his Oxford speech sparked at the time, and the mostly harsh analysis that followed. The Guardian esp. came in for a slagging for publishing Marcus du Sautoy's advertorial of Weinstein and I enjoyed Miles Mathis's acerbic (and it has to be said, conspiracy-laden) critique of that.

But Weinstein seems a more media savvy version of those guys who incessantly post their pet "theory of everything" on reddit etc. insisting that mainstream physicists are suppressing their ideas which are malformed and often not even wrong.

This is a tough call, we can debate peer-reviewed papers but not a video of ideas without clarity or depth.
My vote is that while it is fun to debate this stuff, without any content beyond YouTube, the thread should be locked and another opened when - if - Weinstein publishes his theory and we can link to that.
 
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My vote is that while it is fun to debate this stuff, without any content beyond YouTube, the thread should be locked and another opened when - if - Weinstein publishes his theory and we can link to that.
While some may say this is off-topic I think it should be said: it is exactly this type of bizarre proposals for self-censorship typical of short-term thinking characteristic in contemporary scientific circles that is neither here nor there. Regardless if the theory has been documented per protocol or not, there is clearly a subject for discussion here.

In fact, this raises a broader question about whether any theoretical science can be deemed scientific: is undocumented knowledge deemed 'unscientific' simply because it has not been explicitly documented per protocol yet (e.g. on arxiv or in a journal)? There are literally thousands of manuscripts with unpublished work which while accurate will wrongly be deemed unscientific purely because they have been kept private, e.g. Grothendiecks posthumous unpublished works.

In any case, if the above question is answered in the positive, then basically all truly original and/or novel theories - regardless of their initial tentative or premature presentation, which typically necessitates two or three cycles of reworking to actually become mature and so presentation ready - will systematically tend to be categorized as unscientific, i.e. have an unusually high false-negative rate. Censoring an initial presentation usually translates to premature falsification i.e. forced theory death, instead of pushing it into the cycle of theory maturation.

Moreover, this has an unfortunate side effect that the base rate of initial theory evaluations of even practicing scientists will tend to be off, given that the scientist doing this evaluation isn't an informed and unbiased seasoned expert in theory evaluation, at the level of intellectual honesty of say Feynman. More importantly, thoughtless application of the skeptic strategy is the laziest and quickest way to miss atypical things which shouldn't be missed; it is the hallmark of irresponsibility bordering on intellectual dishonesty.

Fundamentally, this type of irresponsible laziness and overt skepticism has tended to shift the role that doubt plays within the scientific process; doubt is a means to an end, not an end in of themselves. Advocation of lazy skepticism is most often promulgated in scientific circles purely for reasons of holding up appearances of pseudocertainty often reflexively in the face of actual uncertainty. For comparison, in the practice of medicine faking certainty in order to uphold appearances of certainty is illegal and can result in prison; I'm of the opinion similar punishments should apply in the practice of theoretical science.

To summarize, I think Feynman said it best: "I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong. If we will only allow that, as we progress, we remain unsure, we will leave opportunities for alternatives. We will not become enthusiastic for the fact, the knowledge, the absolute truth of the day, but remain always uncertain … In order to make progress, one must leave the door to the unknown ajar."
 
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It is very hard to debate a physics theory off a YouTube video, @Auto-Didact! Vague terminology alone would make it very much a 'he said, she said' situation. I feel you are overextending your outrage in this instance, because PF encourages debate but puts a boundary on the context:

"We wish to discuss mainstream science. That means only topics that can be found in textbooks or that have been published in reputable journals."​

There is deliberately some leeway in a forum such as this one, and @jedishrfu noted this might be an example that warrants continued discourse despite the lack of content. But what can we reasonably glean from Weinstein's talk? There is no formalized math to extrapolate from, no lexicon to define terms, and no citations to link prior art to the new ideas. Is the door ajar to the unknown...or ajar to a pile of doggy-doo?

Shutting down this thread is not a case of shutting down debate. It is merely putting it in abeyance until there actually is something to debate.

(As for your raising the issue of what is debatable, that's definitely worthwhile, but perhaps this thread is not the best place for it.)
 
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mitchell porter said:
[...] so one has to wonder what he's thinking, but maybe this can still help us zero in on what his idea is.
I'd have thought it's Weinstein's job, not ours, to explain clearly what his theory is.

To paraphrase John Baez: "People who cannot express themselves clearly and consisely typically have nothing of value to say. So not much is lost by ignoring them."

[...] But what can we reasonably glean from Weinstein's talk? There is no formalized math to extrapolate from, no lexicon to define terms, and no citations to link prior art to the new ideas. Is the door ajar to the unknown...or ajar to a pile of doggy-doo?
I got the same feelings, and I therefore call "crackpot".

Of course, I'll be happy to retract my "crackpot" call if/when a solid theory arrives, but I'm not holding my breath. :oldfrown:
 
  • #12
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I finally found a straightforward synopsis of the theory, between 02:11:07 and 02:12:34.

"... starting with nothing other than a four-manifold, we built a bundle U. The bundle U had no metric, but it almost had a metric and had a metric up to a connection. There was another bundle on top of that bundle called the chimeric bundle. The chimeric bundle had an intrinsic metric.

"We built our spinors on that. We restricted ourselves to those spinors. We moved most of our attention to the emergent metric on U^14 which gave us a map between the chimeric bundle and the tangent bundle of U^14. We built a toolkit allowing us to choose symmetric field content, to define equations of motion on the cotangent space of that field content to form a homogeneous vector bundle with the fermions, to come up with unifications of the Einstein field equations, Yang-Mills equations, and Dirac equations.

"We then broke those things apart under decomposition, pulling things back from U^14 and we found a three generation model where nothing has been put in by hand and we have a 10-dimensional normal component, which looks like the Spin(10) theory."

To some extent, I feel my work is done. This verbal summary (which would be suitable as an abstract for a paper) should allow any person who actually knows gauge theory and general relativity, to listen to the lecture and judge for themselves how much substance there is to the theory.
 
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