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evanb

5,016 karma

I am a professor of physics at the University of the Virgin Islands [0].

I was previously a staff scientist at Forschungszentrum Jülich [1] and a postdoc at Lawrence Livermore National Lab [2] doing computational nuclear [3] and atomic physics on absolutely gargantuan computers.

[0] https://en.wikipedia.org/wiki/University_of_the_Virgin_Islands

[1] https://en.wikipedia.org/wiki/Forschungszentrum_J%C3%BClich

[2] https://en.wikipedia.org/wiki/Lawrence_Livermore_National_Laboratory

[3] https://en.wikipedia.org/wiki/Lattice_QCD

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bird.onethreenine.net 1mo ago

Apartment Birds Heard Recently

evanb
2pts1
arxiv.org 1y ago

The anomalous magnetic moment of the muon in the Standard Model: an update

evanb
36pts31
arxiv.org 2y ago

Parametric Matrix Models

evanb
66pts7
arxiv.org 2y ago

Synthetic images aid the recognition of human-made art forgeries

evanb
29pts8
www.nytimes.com 2y ago

The Best Security Key for MFA

evanb
2pts0
www.youtube.com 3y ago

Primes and Primitive Sets: an Erdos Conjecture is cracked (2022) [video]

evanb
23pts1
www.youtube.com 4y ago

Primes and Primitive Sets: an Erdos Conjecture is cracked (2022) [video]

evanb
2pts0
writings.stephenwolfram.com 4y ago

The Concept of the Ruliad

evanb
3pts0
www.nasa.gov 4y ago

NASA’s James Webb Space Telescope Has Completed Testing

evanb
2pts0
www.youtube.com 4y ago

Veritasium: Clickbait is Unreasonably Effective [video]

evanb
13pts1
marker.medium.com 4y ago

End of the Line for Uber

evanb
42pts42
en.wikipedia.org 4y ago

Schoonschip

evanb
2pts0
www.npr.org 5y ago

Michael Lewis' 'The Premonition' Is a Sweeping Indictment of the CDC

evanb
70pts134
lamport.azurewebsites.net 5y ago

Time, Clocks, and the Ordering of Events in a Distributed System––Leslie Lamport [pdf]

evanb
2pts0
www.businessinsider.com 5y ago

Unit is attracting retail workers looking for modern ways to organize

evanb
1pts0
www.youtube.com 5y ago

Zero Knowledge Proof Feat. Avi Wigderson [video]

evanb
3pts0
medium.com 5y ago

Waiting for the American Khrushchev

evanb
1pts0
workadventu.re 5y ago

Work Adventure

evanb
1pts0
www.nytimes.com 5y ago

How Eight Covid-19 Vaccines Work

evanb
4pts1
www.youtube.com 5y ago

How Many Potatoes Does It Take to Run Doom? [video]

evanb
3pts0
trumpcovidplan.com 5y ago

Not Found

evanb
5pts1
www.nature.com 5y ago

Room-temperature superconductivity in a carbonaceous sulfur hydride [at 155 GPa]

evanb
2pts0
www.youtube.com 5y ago

Group theory and why I love [the monster] [video]

evanb
9pts0
youtu.be 5y ago

“Real” Programmers and Drum Memory – Computerphile [video]

evanb
2pts0
www.japantimes.co.jp 6y ago

Japan top court tells Twitter to disclose retweeters' info

evanb
119pts100
www.washingtonpost.com 6y ago

Spotify wants to be the go-to for podcasts. Creators and audiences should worry

evanb
1pts0
news.ycombinator.com 6y ago

Ask HN: Good, Affordable Work-from-Home Setup?

evanb
1pts1
arstechnica.com 6y ago

Removing a GPS tracking device from your car isn’t theft, court rules

evanb
42pts7
www.lawfareblog.com 6y ago

Huawei Official Acknowledges Ability to Clandestinely Access Mobile Networks

evanb
10pts5
arxiv.org 6y ago

Periodic activity from a fast radio burst source

evanb
1pts0

The gilded age’s wealthy were also the winners of winner-take-all technologies such as the railroad and oil.

I'm a professor of physics; my research area is computational quantum field theory. I was beginning a new approach for a certain kind of model. I know the model has not been simulated before (a collaborator has just constructed it for the first time using in-field knowledge developed in the last year).

I've been steadily more impressed, but the real startling moment was earlier this week, I could show that in a particular operation I had a bug (some identity wasn't satisfied) but I couldn't understand why. In one try Claude Code grokked my code, explained the problem to me (there were some dimension-dependent minus signs that needed to be computed), and fixed it.

By the Standard Model of Physics Software you can edit Quarkdown in Atom to get Quarkup and change your Neutron Mail to Proton Mail, but it only works if you type with your left hand and create an Electron app and an anti-Neutrinos AI blogpost.

In case the author is reading this, if you're going to introduce the complex-valued harmonics you should be careful to put the complex conjugate in the inner product

    <f, g> = ∫ f(ω)^* g(ω) dω
which does match the corresponding linear-algebra inner product if the vectors are over the complex numbers
    p . q = Σ_i p^*_i q_i
which guarantees that p.p ≥ 0 even for complex p (and does not change the only-real case).

Hmm. As a physicist my intuition is that information-preserving transformations are unitary (unitary transformations are 1-to-1). If a compression algorithm is going to yield a bit string (the zip file, for example) shorter than the original it can't be 1-to-1. So it must yield the zip file and some other stuff to make up for the space saved by the compression.

You could package all your data into a zip using this language but you would also have a worthless stretch of memory seemingly filled with noise / things you’re not interested in.

Isseven 4 months ago

Bug report: I tried 6.999999̅ and got false. So there's some nonstandard model of the reals being leveraged here.

I have always anthropomorphized my computer as me to some extent. "I sent an email." "I browsed the web." Did I? Or did my computer do those things at my behest?

As a term-rewriting system the rule x-x=0 presumably won’t be in Simplify, it’ll be inside - (or Plus, actually). Instead I’d expect there to be strategies. Pick a strategy using a heuristic, push evaluation as far as it’ll go, pick a strategy, etc. But a lot of the work will be normal evaluation, not Simplify-specific.

Mathematica has Infix [0], which expresses the adjacency with a ~ (because Mathematica reserves pure blankspace for multiplication). But it works fine to do eg. `"hello"~StringJoin~" world"`; I was always surprised we could only have the predefined operators in many other languages and we couldn't define our own.

This seems like a great attempt. I would be worried about how much parsing and backtracking might be required to infer the infix precedence in a totally general system (like garden-path sentences[1]) or actually ambiguous parse trees (which is cured by adopting some rule like right precedence and parens, but what rule you pick makes some 'natural language' constructions work over others).

[0] https://reference.wolfram.com/language/ref/Infix.html

[1] https://en.wikipedia.org/wiki/Garden-path_sentence

They did consider it, got a contract that affirmed that the military would be bound by the same pre-existing terms of service as every other user, and want to resist the military's pressure to renegotiate.

Surely that might be naive but the entire issue is that they want to stick to the original contract, which is of course the purpose of a contract in the first place.

I'm using these to teach an intermediate mechanics class, and my only regret is that there are no problems. The flip side is that sometimes Feynman skips over the derivations of certain things, and that makes good assignments ("Fill in the steps between [these assumptions] and [this result]").

Feynman's writing of course is stellar. The order is a bit unusual and not really designed for a "standard" university-level course. I can pick and choose, but I wish I could easily reorder the material.

Bob Weir has died 6 months ago

Winter rain, now tell me why

Summers fade and roses die

The answer came, the wind and rain

[...]

Circle songs and sands of time

And seasons will end in tumbled rhyme

And little change, the wind and rain

Fare thee well, Bob.