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|usernameurl=https://x.com/EricRWeinstein | |usernameurl=https://x.com/EricRWeinstein | ||
|username=EricRWeinstein | |username=EricRWeinstein | ||
|content=I would say the one who awes me most is...CN Yang. I don’t understand why I never hear his name as candidate. He has at least 3 of the greatest achievements: chirality for the weak force (w/ Lee), non-Abelian maxwell theory (w/ Mills), and the bundle revolution (w/ Simons/Wu). | |content=I would say the one who awes me most is...[[CN Yang]]. I don’t understand why I never hear his name as candidate. He has at least 3 of the greatest achievements: chirality for the weak force (w/ Lee), non-Abelian maxwell theory (w/ Mills), and the bundle revolution (w/ Simons/Wu). | ||
|thread= | |thread= | ||
{{Tweet | {{Tweet | ||
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Peter Woit</br> | Peter Woit</br> | ||
John Baez</br> | John Baez</br> | ||
Ed Witten</br> | [[Ed Witten]]</br> | ||
Luis Alvarez Gaume</br> | Luis Alvarez Gaume</br> | ||
Dan Freed</br> | [[Dan Freed]]</br> | ||
Jose Figueroa O’Farril | Jose Figueroa O’Farril | ||
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The quantum is real. It’s mysterious. It’s mind blowing. And as a result it provides jobs and something to talk about when the classical theory is stagnant. But the dream of quantum theories that are born quantum never materialized. We still quantize classical theories, for all our posturing about needing to take classical limits of quantum theories. | The quantum is real. It’s mysterious. It’s mind blowing. And as a result it provides jobs and something to talk about when the classical theory is stagnant. But the dream of quantum theories that are born quantum never materialized. We still quantize classical theories, for all our posturing about needing to take classical limits of quantum theories. | ||
Witten in particular popularized the notion that the incompatiblity between General Relativity and the Standard Model is a Classical vs Quantum problem. He’s wrong. | [[Ed Witten|Witten]] in particular popularized the notion that the incompatiblity between General Relativity and the Standard Model is a Classical vs Quantum problem. He’s wrong. | ||
The Classical GR theory is already incompatible with the Classical Standard Model. The incompatibility is already classical: NOT Quantum. | The Classical GR theory is already incompatible with the Classical Standard Model. The incompatibility is already classical: NOT Quantum. | ||
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|content=Gave a talk at Hebrew University Physics Department today on the geometric basis for Dark Energy. | |content=Gave a talk at Hebrew University Physics Department today on the geometric basis for Dark Energy. | ||
Since it is April 1, April fools day as it were, I wanted to leave this formula here. For the future. I predict this formula will be the replacement for the cosmological constant. | Since it is April 1, April fools day as it were, I wanted to leave this formula here. For the future. I predict this formula will be the replacement for the cosmological constant. | ||
|timestamp=8:57 PM · Apr 1, 2025 | |timestamp=8:57 PM · Apr 1, 2025 | ||
|media1=Gnel_Y_XQAAjRPF.jpg | |media1=ERW-X-post-1907175481851412790-Gnel_Y_XQAAjRPF.jpg | ||
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exploring this with you in depth. | exploring this with you in depth. | ||
|timestamp=9:11 PM · Apr 1, 2025 | |timestamp=9:11 PM · Apr 1, 2025 | ||
|media1=GnepTEmXgAAdVOI.jpg | |media1=ERW-X-post-1907179119659356409-GnepTEmXgAAdVOI.jpg | ||
}} | }} | ||
|timestamp=9:29 PM · Apr 1, 2025 | |timestamp=9:29 PM · Apr 1, 2025 | ||
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|image=Eric profile picture.jpg | |||
|nameurl=https://x.com/EricRWeinstein/status/1928095740926251169 | |||
|name=Eric Weinstein | |||
|usernameurl=https://x.com/EricRWeinstein | |||
|username=EricRWeinstein | |||
|content=Ah. It has two features that general Ehressmanian geometry generally lacks: | |||
I) A distinguished Choice of Connection (The Levi Civita connection and the connections induced from it on associated bundles). | |||
II) Tensor Decomposition coming from the lack of structure groups auxiliary to those of the tangent bundles. | |||
So actually the specific sub geometry of (pseudo)-Riemannian geometry is an exchange of Gauge Symmetry and field content freedom for these two attributes. | |||
Except in totally exotic cases. Like the one in which we oddly happen to live…but I digress. | |||
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|image=HeathHimself-profile.jpg | |||
|nameurl=https://x.com/HeathHimself/status/1926519377404285084 | |||
|name=Heath | |||
|usernameurl=https://x.com/HeathHimself | |||
|username=HeathHimself | |||
|content=@EricRWeinstein Caught your debate with Sean Carroll on Piers. Why do you think he was spouting off so much misinformation about GU? "There's no Lagrangian!" I'm looking at the paper right now. There's literally 3 pages worth of Lagrangians like wtf. | |||
|timestamp=6:03 AM · May 25, 2025 | |||
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|nameurl=https://x.com/Neon__Genesis_/status/1927831447164928207 | |||
|name=Neon | |||
|usernameurl=https://x.com/Neon__Genesis_ | |||
|username=Neon__Genesis_ | |||
|content=The whole debate was very odd, Carroll didn't offer a single criticism of any substance, not a single concept or equation. We need to remember Sean at heart is a philosophy and astronomy major, not a mathematician or physicist despite their self-styling | |||
|timestamp=8:56 PM · May 28, 2025 | |||
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Let me put them in the language of GU. | Let me put them in the language of GU. | ||
“The Chern-Simons Lagrangian has been studied previously in (2+1)-dimensional spacetime, where it is both gauge and Lorentz invariant. We the authors believe that outside of this special dimension, there is a fundamental trade off where we must either violate Ehresmannian Bundle Geometry (Gauge Theory of Particle Theory) or the pointwise Lorentz Invariance of Riemannian Geometry (Einstein’s General theory of Relativity). It appears to the authors that the right way to construct an analogous term in 3+1 dimensions is to create a Chern Simons-like term which couples the dual electromagnetic tensor to an artificial external four-vector which has no supporting evidence or motivation and violates both Einstein’s Special and General theories of Relativity. If we take this four-vector to be fixed, the term is gauge invariant but not Lorentz invariant throwing out one of the two pillars of modern physics. We do it anyway, because we believe the above mentioned tradeoff precludes any other approach.” | “The Chern-Simons Lagrangian has been studied previously in (2+1)-dimensional spacetime, where it is both gauge and Lorentz invariant. We the authors believe that outside of this special dimension, there is a fundamental trade off where we must either violate [[Bundles|Ehresmannian Bundle Geometry (Gauge Theory of Particle Theory)]] or the pointwise Lorentz Invariance of Riemannian Geometry (Einstein’s General theory of Relativity). It appears to the authors that the right way to construct an analogous term in 3+1 dimensions is to create a Chern Simons-like term which couples the dual electromagnetic tensor to an artificial external four-vector which has no supporting evidence or motivation and violates both Einstein’s Special and General theories of Relativity. If we take this four-vector to be fixed, the term is gauge invariant but not Lorentz invariant throwing out one of the two pillars of modern physics. We do it anyway, because we believe the above mentioned tradeoff precludes any other approach.” | ||
I personally knew Sean’s co-author Roman Jackiw decently well on this topic as he was at MIT. This was his perspective. | I personally knew Sean’s co-author Roman Jackiw decently well on this topic as he was at MIT. This was his perspective. | ||
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Sean’s work is the DIRECT competitor of this GU theory. And GU sacrificed neither. | Sean’s work is the DIRECT competitor of this GU theory. And GU sacrificed neither. | ||
|media1=ERW-X-post-1928085868054729136-GsHv4ISaUAcvL0z.jpg | |||
|timestamp=1:47 PM · May 29, 2025 | |timestamp=1:47 PM · May 29, 2025 | ||
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|nameurl=https://x.com/uniservent/status/1928093271336665134 | |||
|name=UniServEnt | |||
|usernameurl=https://x.com/uniservent | |||
|username=uniservent | |||
|content=Given info on this link, why do you need Riemannian geometry in the first place if it is a subset of Ehressman? | |||
https://chatgpt.com/share/68386b13-93e0-8013-a47d-75b2769f464d | |||
|timestamp=2:17 PM · May 29, 2025 | |||
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|timestamp=2:27 PM · May 29, 2025 | |||
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|timestamp=5:02 PM · Oct 15, 2025 | |timestamp=5:02 PM · Oct 15, 2025 | ||
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== Related Pages == | == Related Pages == | ||