David Moore

Weyl spinor. The Weyl equation is the zero mass version of the Dirac equation. The Weyl spinors travel at the speed of light. To see this I have added a vertical dotted yellow line that moves rightwards at c. As you can see the wave packet moves at c also.

@TradeTexasBig The comments have the answer! Looks like @gro_tsen posted the stackexchange answer referenced in the comments there. #822208" target="_blank" rel="nofollow noopener">math.stackexchange.com/questions/8206… Super cool, thanks for sharing.

Is this true ?

Heck yeah! I never learned the classical Onsager solution per se, just the 1D quantum transverse field ising model, which maps into the 1+1D Ising model. I learned from mcgreevy.physics.ucsd.edu/s14/239a-lectu… pp.48-54 Also I've been meaning to read Kauers' and Zeilberger's arxiv.org/abs/1805.09057 And Ulli Wolff's arxiv.org/abs/2003.01579

@physbuzz2 Next week I'll calculate 2D Ising！

1次元Ising模型の強磁性-常磁性相転移が有限温度では起きないことを厳密に示したよ

@codetaur Yeah u right. Really at this point it's just historical habits.

@physbuzz2 even if you need to do the computation outside of webgpu, do the visualizing of the data in webgpu

every time I see people doing cool math visualization stuff with like, python generating svgs or pngs I just want to shake them and say "USE WEBGPU. MAKE THIS REALTIME. EXPLORE THE ENTIRE SPACE OF POSSILITIES AT WILL, PLEASE!"

@QiaochuYuan Except for quantum information, which is really a theory of information. (My mood immediately dampens when I think I can apply some conclusion from q info, but it doesn't have the same physical significance in regular info theory or is only a small/trivial sub-picture)

"information theory" as a name is just advertising, it's not really a theory of information at all. information in the human sense necessarily includes a value-laden notion of relevance / importance / meaningfulness which information theory doesn't and can't track at all

(just memeing, carry on.)

@F_undergraduate So many uses for this book! You can use it to learn QFT, you can use it to learn CFT, you can use it to press flowers, you can learn radial quantization or even prop your door open. One of the most versatile books in the theoretical physicist's library.

yellow bookってこれか amazon.co.jp/gp/product/146…

I got invited to a conference in 2019 for some silly math stuff I did on Google+ in like 2013 as a freshman so it really does help! On the "being anonymous sucks" front: I was posting a bunch on stackexchange in 2013-2018, got 10k or 20k fake points, did a ton of stuff answering questions and writing programs on khanacademy cs to help other people learn... but it was all anonymous and I was so good at being anonymous I deleted accounts such that I can never get that info back. So like I know I've answered @QiaochuYuan's physics questions during one of his physics arcs but I can't go back to find those answers! (I'll just show up as "user10502305" or whatever). Also it has come up that having that profile around would have helped me in a few interviews. On the other hand: I can't (won't) touch politics with a ten foot pole, which is morally questionable. If I dunk on someone or say their paper sucks I'll have to answer to that or look like an idiot IRL (which I think is fine). And internet people are not above digging through 10k tweets or 1k hours of stream to find the worst moment to try to get you fired. Also it makes spearphishing way easier. The nail in the coffin was that in retrospect, when I did nothing potentially controversial or cringe, and did nothing that could reflect poorly on me, I did nothing at all! So I'm done with being anonymous lol. But also for sure lots of people stay anonymous without any of the effects I just mentioned, I'm just giving an N=1 example of why I couldn't do it.

i genuinely dont know if i should add my personal info to this account to help my career if i say something smart on here, or if i should keep anon to say stupid stuff

Do your part, post a cool application of a SAT solver.

I quite like this: arxiv.org/abs/1604.06722 finding the minimum energy configuration of a generalized Ising model. The Huang et al papers on this are very good but -- they don't have any pictures of the ground states! (which will just be black and white pixels on an infinite plane, they're not groundbreaking) I did a little summer project on this but I wasn't familiar enough with SAT, branch and bound, etc. so I ended up spending most of my time just learning that. community.wolfram.com/groups/-/m/t/3… The story I put together from Huang et al is: "Branch and bound! No, a recursive cluster tree! Wait actually, just hit it with a SAT solver lol."

What are some very cool applications of SAT solvers you know?

@indefeasible_ I learned from Velleman's book + a tutor who answered my questions every 2wks, 10/10 would recommend.

can anyone recommend me a intro to proofs book/lecture notes to read this summer?

@irfnali1 Oh this looks really cool, thanks for the link!

@physbuzz2 Very nice! Reminds me of section 8 of The Matrix Cookbook, but with a distinct focus on physics use cases. #page40" target="_blank" rel="nofollow noopener">math.uwaterloo.ca/~hwolkowi/matr…

Wrote some silly/excessive notes on finite dimensional Gaussian integrals for QFT. Web: mathandcode.com/2026/05/18/gau… Markdown source for chucking into LLMs: github.com/physbuzz/matha…

Hm definitely needs another typo pass but it can wait til next weekend.

@star_stufff Yaa I feel a bit silly because this is like, the 1+1=2 of hep-th, but it should be a good reference for more cool animations and graphs and lattice sims!

@physbuzz2 Nice!

Man I love Twitter, such a good thought piece. Anki-style flashcards helped me a ton in undergrad/grad physics and math... for Fernando's example of a flash card testing the knowledge "Are all unitary matrices invertible?", I'd write: "Q: Define what it is for a matrix to be unitary. What about for a general linear operator in an inner product space?" In general anki-style quizzes helped me a lot, even in graduate school physics qualifying exams. I'd literally have on a flash card, "derive the Einstein Field Equations from the Hilbert action." For a question like that, the goal is not to get out a few sheets of paper and scrawl everything out, but to carry out the argument in your head adequately. If I ran through the whole argument in my head and piece-by-piece only said "yep, I know how to do that" then I considered it answering the question successfully without writing anything down! There'd also be an army of supporting questions so saying "skip, I don't remember enough to answer that" is perfectly valid. My memory is trash so it's pretty important for me. Actually it would be super fun to go over some flash cards I made back in, jeez, 2015, for a group theory course. I think the top three scores on the final exam were like 115%, 108%, 60% 😆 I conceded second best but the point is the flash cards helped! FWIW I find ChatGPT 5.5 pro and Claude opus 4.7 to be frustrating and ~break-even effortwise for writing math 'n' physics flash cards (half decent for generating ideas and great for verbose technically-correct-but-misses-the-salient-point answers, but very little makes it into the final output).

@OnuncuSoru Sitting at 0+i glad to be away from all the hustle and bustle of the real line

Illumination 1:

@backslashvarphi oh no did i hurt a physicists feelings? should we build a new supercollider? should we call Michio Kaku? GO DO MATH