Quantum Field Theory: Difference between revisions

There was an underlying political economy to the issue masked by “shut up & calculate”. I agree that the quantum field theorists were often, and words fail me, dicks about quantum foundations. But it was really an overlay on a rational calculation of expected return from 1928-74.

10:09 PM · Sep 8, 2019

2020

This is at the heart of my disagreement with @skdh. I am doubly contrarian with respect to QFT. I believe that many of the things they tried say were abstractly reasonable but clearly misinstanciated. To make their mere calculations beautiful, they were creating a hideous world.

4:08 PM · Jan 29, 2020

2021

In strong GU:

SU(3) x SU(2) x U(1) (Standard Model)

Is contained in U(3)xU(2) inside

Spin(6)xSpin(4) =SU(4)xSU(2)xSU(2)

(Before the more difficult non compact Spin(6,4).)

I’d look first to the extra 1D reductive U(1) if the experiments hold up. Then to Spin(6) x Spin(4):

7:02 PM · Apr 7, 2021

11

@11Equity

@EricRWeinstein What are your thoughts on this and how does it fit with Geometric Unity? https://www.bbc.com/news/56643677

4:25 PM · Apr 7, 2021

As far as Fermion quantum number predictions that could open up new channels, Strong GU makes clear predictions. Explicitly, here would be the next Spin-1/2 particles internal symmetries we should find:

7:02 PM · Apr 7, 2021

Additionally, Strong GU predicts that there will be 16 Spin-3/2 particles with Standard model symmetries conjugate to the Spin-1/2 generations and gives their ‘internal’ quantum numbers as:

7:02 PM · Apr 7, 2021

Now, why if GU makes predictions do I appear to some to shy away from them?

A: I don’t.

But string theorists hide the fact that they disconnected themselves from normal science by trying to force everyone else *except* String Theorists into answering hyperspecific challenges.

7:02 PM · Apr 7, 2021

Thus while I can tell you what GU predicts is next, they push for a QFT calculation of energy scale to make others sound vague.

So let’s talk vague: Look at the above containments and SM quantum numbers. That’s not vague. Now ask String Theorists the SAME question...and compare.

7:02 PM · Apr 7, 2021

Lastly: I would caution about getting too far ahead of our experimentalist friends. Let them sort out their confidence and not push them to be too definite prematurely.

But my advice is to watch *relative* predictive responses of those w/ “Beyond the Standard Model” theories. 🙏

7:02 PM · Apr 7, 2021

P.S. Happy to attempt to sharpen what GU can say. But not working on my own outside the community. If you want more precise predictions than I already have, I’d need access to normal resources (e.g. constructive QFT colleagues). Working outside from home it’s probably impossible.

7:02 PM · Apr 7, 2021

P.P.S. Remember that GU rejects three generations. In GU it’s 2 True generations plus 1 imposter. A priori, this could also be an effect of the imposter not being a true generation.

Again I would need QFT colleagues trying to help me see if that is a possible effect.

7:11 PM · Apr 7, 2021

@robnormal That’s the beginning. Then that the listeners be *highly* motivated. Also intelligent. Also, that no listeners are trying not to understand. Etc

Pretty soon it’s stone soup. You’re no longer explaining things quickly at a party but you’re now teaching QFT courses at university.

2:55 PM · Dec 15, 2021

Things got hard. They didn’t get hopeless.

Yes we spent almost 40 years lying about string theory. But we could stop today. We could have the leaders in the field admit they made a *colossal* bad bet & ask “What did we dispose of while we were wildly over-hyping string theory?”

12:47 AM · Dec 23, 2021

🇺🇲TradeTexasBig🇮🇳

@TradeTexasBig

Its increasingly apparent to me that the next physics breakthrough is gonna be from #ai . Its humanly not possible anymore for theoretical physicists ..i was feeling it even around 2010

12:17 AM · Dec 23, 2021

Sabine Hossenfelder

@skdh

They can't stop, Eric. They're making a living from writing papers about things no one will ever see. It's a systemic problem that requires a systemic response. And the first step would be to admit they have a problem (which they don't).

4:25 AM · Dec 23, 2021

WeLivetoServe

@WeLivetoServe

Seems likely a lot of the math they developed will wind up handy, but it's a long time to wait for dessert.

4:30 AM · Dec 23, 2021

Sabine Hossenfelder

@skdh

Most of what physicists call math is totally uninteresting even for mathematicians. It's just advanced calculus. Look here is my qft and when I crunch it cross-sections fall out.

4:33 AM · Dec 23, 2021

We may disagree intellectually more than I thought. This is Jackiw’s point: the era of physics thinking of mathematics as advanced calculus (analysis) wasn’t fruitful.

That changed around 1975 when the quantum began to discover geometry.

I’m honestly confused. What do you mean?

3:00 AM · Dec 24, 2021

Sabine Hossenfelder

@skdh

We are talking past each other. I am referring to particle physicists/astrophysicists/cosmologists who crunch out shallow and useless papers in the thousands. There's no interesting math in those. You're talking about something else entirely.

5:15 AM · Dec 23, 2021

QFT & cross-sections sound more like particle theory than Astrophysics, Cosmology or even GR.

Would we agree that the collision of Witten/Singer/Quillen/Seiberg/Freed/Bismut/Maldacena/Penrose/Atiyah/ Hitchin/Dijgraff/Vafa/Segal/Jackiw/Kontseivich/Alvarez-Gaume/etc has been magic?

6:11 AM · Dec 24, 2021

There are a lot of string theorists who have done things that really matter to geometry, topology, analysis on manifolds, representation theory. And I don’t want to misunderstand your point.

6:13 AM · Dec 24, 2021

Said differently I’ve been bullish on positive externalities of mathematical physics. But a lot of great math that got done isn’t string theory. It’s claimed to be stringy but it is really mostly mathematical physics or geometric field theory that is claimed by string theorists.

6:16 AM · Dec 24, 2021

2022

That wasn’t shared with me. I don’t mind that we explore whether GR researchers or QFT theorists are more likely to believe in TOEs than say condensed matter folks. But I’m not up for reifying alleged oppression of [irrelevant identity group A] over [irrelevant identity group B].

10:05 AM · Jan 3, 2022

Physics in 1980: “I’m trying to grasp why nature has 3 generations of chiral fermions with SU(3)xSU(2)xU(1) internal symmetry.”

Physics Today: “Remind me again what the internal quantum numbers are? I do quantum gravity so it’s not something I’ve worked with since my QFT class.”

3:24 PM · Aug 24, 2022

Martin Bauer

@martinmbauer

What has string theory done to become the poster child of failed physics? It hasn’t even failed.

4:56 PM · Aug 23, 2022

A) High energy physics of real particles became the no-energy physics of toy models.

B) Quantizing Gravity was substituted for unification or extension of the Standard model.

C) Other research programs were obliterated because ST claimed it had it all rapped up.

D) Hype won.

3:34 PM · Aug 24, 2022

E) Focus shifted to mathematical structure of abstract field/String/M theory. Not our particular world’s choice of thy.

F) Standards of scientific progress were rewritten to disguise failure.

G) Differential application of standards became the norm.

It ended physics culture

3:34 PM · Aug 24, 2022

String Theory isn’t the problem. String culture is poisonous to science.

String theory, like love, means never having to say your sorry. Or mistaken.

It’s the January 6 problem…but in science. But where the physics versions of Mike Pence often got fired for not going along. 🙏

3:41 PM · Aug 24, 2022

*you’re

3:44 PM · Aug 24, 2022

P.S. “It hasn’t even failed” because it can’t fail. So far as I can see, it can never fail. In the minds of the faithful, It’s unable to fail because it *has* to be the way forward. It’s hard to explain what’s wrong with that to the enlightened who see its infinite power & glory.

3:50 PM · Aug 24, 2022

Martin Bauer

@martinmbauer

What has string theory done to become the poster child of failed physics? It hasn’t even failed.

4:56 PM · Aug 23, 2022

@MadsOlesenDK Nah. I would study basic GR. It’s a bit steep, but not as bad as QFT to learn by a long shot.

4:36 PM · Nov 7, 2022

2023

Prof. Brian Keating

@DrBrianKeating

In studio Episode of @Into_Impossible with Dan coming soon where we discussed his epic 🧵. And Martin and Eric and Turok and Sabine get shoutouts! Stay tuned…

4:16 PM · Feb 2, 2023

Martin Bauer

@martinmbauer

Hard to tell whether this is good faith, honestly. Some grains of truth buried here, but you have to ignore many developements to end up w this view.

I'll leave this here https://x.com/nu_phases/status/1598331715340054528

8:40 AM · Feb 2, 2023

Prof. Brian Keating

@DrBrianKeating

But Martin, with Eric in my experience, it’s always good faith… l’Shem Shamayim as we say!

4:20 PM · Feb 2, 2023

Of course! We all fail…or we aren’t pushing ourselves. We have to confront what happened. But, to give @martinmbauer his due, his papers are genuine attempts to understand the physical world. He is one sort of theorist we need more of. 4D SM + extensions. That’s not QG theology.

5:19 PM · Feb 2, 2023

I’m much more concerned by brilliant theorists who…and I am not kidding at all…refer to the Standard Model as “Oh, I vaguely remember this from graduate school QFT class.” That is an unbelievable development. People who have literally forgotten the field content of reality.

5:22 PM · Feb 2, 2023

And I don’t want to get rid of them. I want us to go back to real physics. I want us to stop pretending we live in anti-de Sitter Space or that space time SUSY is just out of reach.

It’s basic to the culture of science. Which unfortunately is not QG culture.

5:25 PM · Feb 2, 2023

@nu_phases @martinmbauer And as per the Renormalization Revolution, a non fundamental result can unlock further fundamental ones as we saw after the late 40s. YM QFT wasn’t built in a day after all.

But my point stands along side your point. We don’t seem to be able to push the fundamental physics. 🙏

11:45 PM · Feb 2, 2023

“String Theory is absolutely…the most likely to be true set of ideas about what sits at the intersection of the Standard Model and quantum gravity.”

8:16 AM · Jul 7, 2023

I can confirm this indeed blows up ones notifications.

But, in case of doubt or misunderstanding, string theory is absolutely the deepest, most consequential and most likely to be true set of ideas about what sits at the intersection of the Standard Model and quantum gravity.

8:16 AM · Jul 7, 2023

Yes, that is precisely what I think.

8:21 AM · Jul 7, 2023

If you said “electrons are absolutely fractional spin fields in the standard model” I wouldn’t disagree with that statement. It isn’t at all about what you think. It is a true statement.

Here you are assuring lay people about what is absolute about String Theory within physics.

8:38 AM · Jul 7, 2023

My responsibility is to make accurate statements (and yes, everything is my (professional) opinion).

As the book quote indicates, I try not to overclaim. But: that string theory and the complex of ideas are around it are more serious than any competitors, IMO objectively true.

9:15 AM · Jul 7, 2023

“IMO objectively true”

As with so many of these String Theoretic claims I have no idea what that means.

So for example if I make an argument that this is NOT objectively true, do you fall back on the idea that it was opinion?

“Objectively, Electrons are field theoretic at observed energy scales.” My opinion doesn’t enter into it. The claim that it is objectively true eliminates the role of opinion.

Does that mean that all who disagree with you and your String community are “not serious” as per the above?

5:27 PM · Jul 7, 2023

The arguments become more convincing/objective, the more one can use graduate-level theoretical physics in them.

But in 280 characters and no equations, it’s hard to develop these

In a book, easier to do so.

10:12 PM · Jul 7, 2023

I don’t think that’s the issue Joseph. At all.

Feynman, Glashow, Wilczek never found them objectively or absolutely compelling.

String theorists like Friedan have written harshly of the Failures.

And what you are saying about subjective opinion and absolute objective fact doesn’t make sense. I mean you can just see that, no? Not trying to be mean here. But I don’t see what you are claiming is absolute and objective beyond your opinion.

What you seem to be saying is the usual trope: “The more you understand about the difficulty of quantizing a spin 2 gravitational field the more you appreciate how string theory has taught us so much about how it is to be done eventually, and that there is no remotely comparable framework for doing so!”

Again. Not trying to be combative. Feel free to correct me if I have this wrong.

10:48 PM · Jul 7, 2023

It is not objective or absolutely true that String Theory is our best theory. In fact, it has become, 40 years after the anomaly cancelation, our most thoroughly explored idea. No other path has been picked over like this one.

Waited a few days. I don’t think you are making sense about your *opinion* that it is *objectively* and *absolutely* dominant. And that is the problem. String theorist deliberately leave others with the impression that they are following something scientific, objective and absolute. But it is really just a shared subjective hunch. And this does science and physics a terrible disservice.

11:59 PM · Jul 10, 2023

The question about where string theory stands in comparison to other approaches to quantum gravity. I think it objectively true that string theory has given lots of stuff that is useful/foundational to cognate areas (eg QFT) than any other approach to quantum gravity. 1/n

6:00 AM · Jul 11, 2023

Holography and AdS/CFT is the clearest example but there are others.

I think this is objectively, uncontroversially true — once people have the background in theoretical physics that they understand topics like QFT on a technical level and have some real sense of the subject.

6:03 AM · Jul 11, 2023

But most people (reasonably) don’t have this background. So I preface this with ‘my opinion’ in recognition that the core and guts of the argument, and the real reasons behind it, are not accessible to most people who read these tweets.

6:07 AM · Jul 11, 2023

This is not ideal - but while saying ‘go buy my book’ is a slight cop out, the book is my full argument at a level as non-technical as possible of why string theory has the position it does DESPITE the lack of direct experimental evidence for it

6:09 AM · Jul 11, 2023

Joseph. Imagine I were to temporarily stipulate to the idea that of all the known approaches to quantizing the metric field that leads to gravitation, String Theory is by far the most advanced. I don’t think that is unreasonable whether or not it is true. It’s a solid argument.

3:14 AM · Jul 13, 2023

I don’t think that is the relevant argument anymore. So you are framing it in such a way that “String Theory” is the answer to a question you formulated: “Of all the approaches to quantizing gravity which haven’t worked, which is the best?”

My argument is with that framing.

3:19 AM · Jul 13, 2023

The problem I have is with string theorists framing of the field and its issues and questions. I think String Theory is dangerous for this reason.

Try these instead:

A) Which approach is most likely to successfully alter or explain the Standard model?

B) Same as A) but for General Relativity?

3:22 AM · Jul 13, 2023

C) Which approach is most likely to shed light on why there are 3 generations of observed fermions?

D) Which approach is most likely to shed light on why the generations are chiral?

E) Which large community most regularly makes sweeping claims that it later must privately invalidate while publicly claiming a new revolution?

F) Which large community is most likely to ignore other ideas?

G) Which is the most aggressive large community despite no proven connection to observed reality?

3:27 AM · Jul 13, 2023

H) Which community is most likely to spend all their careers working on toy models with the wrong dimensions, signatures or field content claiming that we are building up the toolkit?

I) Which community is least likely to own up to the disaster of past public declarations about accessible energy SUSY?

3:30 AM · Jul 13, 2023

J) Which approach has been the most investigated and thus thoroughly picked over for low hanging fruit?

K) Which approach best explains the odd nature of a seemingly fundamental Higgs sector?

L) Which approach is most dogmatic that “Quantum Gravity” rather than “Unification” or “Gravitational Harmony” or “Incremental understanding” etc. *Is* the path forward when we don’t even know if gravity is quantized as we expect it at all in models beyond relativitistic QFT?

3:36 AM · Jul 13, 2023

M) Which approach comes closest to explaining the origin of the internal symmetry structure group of the Standard model?

N) Which approach comes closest to explaining why there appear to be 16 particles in a generation with their observed internal quantum numbers?

3:38 AM · Jul 13, 2023

O) Which approach is most at risk of invoking “The Landscape” of impossibly many theories to test after saying that the power of the approach was that there were only 5 possible theories?

P) Which community brags about “postdiction” the most because it has failed at predictions?

3:42 AM · Jul 13, 2023

Q) Which community is least collegial and most insulting to colleagues outside the approach?

R) Which HEP theory community consumed the most in resources over the last 40 years?

S) Same for brains?

T) Same for producing PR and puff pieces?

U) Which community has broken the most trust with lay people in HEP theory?

3:45 AM · Jul 13, 2023

V) Which community substitutes mathematics results for results about the actual physical world we live in when talking to the public?

W) Which community is most likely to restore the culture of successful physics research to HEP theory?

X) Which not yet successful approach has been most self-critical?

Y) Which community is most respectful in absorbing the results by others with proper credit?

Z) Which community relentless makes its argument by mis framing the question as if the question were simply “What is our deepest collection of ideas of how to quantize a massless spin 2 gravitational field?” when the previous 25 framings are all arguably more important after 39 years without contact with physics?

3:51 AM · Jul 13, 2023

That is why this conversation doesn’t work. It is what magicians call “Magicians Choice”: the lay person is lead into thinking they are free to disagree. But the question you keep asking is DESiGNED to make it look like String Theory is our top community.

Joseph: it failed in the terms it gave for taking over. It chose the terms. It said what it was and what it was going to do. And it flat out failed in EXACTLY those terms it chose when it said “Hold my beer!” back in 1984.

3:56 AM · Jul 13, 2023

To sum it up: when string theorist are no longer in a position to keep changing the goal posts set by the physical world, isn’t it the case that from A-Z maybe string theory is not being honest?

Again. Not personal to you. At all. But it is not a fair move to say “It’s the best yet-to-succeed approach to quantum gravity.” in front of the public. No?

🙏

4:00 AM · Jul 13, 2023