evanb

76 ms·

841.
by evanb 10y ago
That's right. Quantum mechanically, potentials are generated by the exchange of off-shell mediators (the clearest explanation I have seen is in Zee's QFT in a Nutshell). https://en.wikipedia.org/wiki/On_shell
842.
by evanb 10y ago
Well, just think about the Dark Scientist who says "OK, we make up 27% of the universe, and there's a missing 5% we don't see because it doesn't interact with us." And then some dark model builder says, "Guys,
843.
by evanb 10y ago
While that's the common understanding, general relativity tells us that the spacetime curvature is dictated by the stress-energy tensor, which is accounts for all different types of mass and energy. For example, if you have a crystal
844.
by evanb 10y ago
You might enjoy his talk on what a computer actually is: https://www.youtube.com/watch?v=EKWGGDXe5MA
845.
by evanb 10y ago
First-rank symbolic calculation is absolutely critical.
846.
by evanb 10y ago
I read it before and during a trip to Israel. Changed the way I saw everything.
847.
by evanb 10y ago
Bradbury: Now and Forever: Somewhere a Band Is Playing & Leviathan '99 Gleick: The Information Michener: The Source Martin: A Song of Ice and Fire (all of them, digital)
848.
by evanb 10y ago
I subscribe to the arXiv rss feeds of hep-lat and nucl-th.
849.
New movie screen allows for glasses-free 3-D at a larger scale(news.mit.edu)
2 points by evanb 10y ago|0 comments
850.
by evanb 10y ago
This reminds me of the Hawaii Overprint Note of US currency during WW2. Perfectly legal---but marked so that were Hawaii to fall it would not enrich Japan. https://en.wikipedia.org/wiki/Hawaii_overprint_note
851.
by evanb 10y ago
From the article: > We can formalize the above considerations by giving rules for a toy language L over an alphabet A. In the parlance of theoretical linguistics, our language is generated by a stochastic or probabilistic context-free g
852.
by evanb 10y ago
Max Tegmark is a cosmologist who writes ~5 serious papers and then one "out there" paper. https://en.wikipedia.org/wiki/Max_Tegmark
853.
by evanb 10y ago
Minor erratum: 's/3 spins/3 colors/'.
854.
by evanb 10y ago
KenoFischer is right---it comes down to gauge invariance. Gauge symmetry is a local symmetry that dictates a lot of the structure of QCD. If your discretization breaks it (and say, only recovers it in the continuum limit) you will have ver
855.
by evanb 10y ago
I do lattice QCD, and this is a pretty decent explanation. A few minor things: People typically use lattice sizes that have lots of factors of 2, because they fit on the supercomputers in a better way. So rather than 100 people do 96 or 12
856.
by evanb 10y ago
This is true if the system you're trying to describe is weakly coupled. If the theory is strongly coupled, then in fact more and more complicated diagrams count more and more. In this case the method of Feynman diagrams because basica
857.
by evanb 10y ago
This reminds me of the excellent computerphile video https://www.youtube.com/watch?v=-5wpm-gesOY
858.
Facebook is shutting down its Paper newsreading app on July 29th(theverge.com)
2 points by evanb 10y ago|1 comments
859.
by evanb 10y ago
It's a perfectly cromulent word. https://www.youtube.com/watch?v=FcxsgZxqnEg
860.
How Bayes’ Rule Emerged Triumphant from Two Centuries of Controversy(mcgrayne.com)
152 points by evanb 10y ago|80 comments
861.
by evanb 10y ago
"Flush" in the poker context has more to do with definitions 1 (Abundantly full. In later use chiefly of a stream, etc.: Full to overflowing, swollen, in flood.) and 3 (Plentifully supplied (esp. with money).) rather than 5 (Even,
862.
by evanb 10y ago
They always have at least one doctor at the pole over the winter. They have two hospital beds, an operating table, and a relatively extensive pharmacy. If someone's coming home, it's because it's extremely serious.
863.
AT&T Archives: The Unix Operating System [video](youtube.com)
2 points by evanb 10y ago|0 comments
864.
by evanb 10y ago
Well, thanks! Now if you know any tenure-track job openings looking for a lattice gauge theorist / nuclear physicist... I do side projects on string theory and BSM physics, if that helps :P
865.
by evanb 10y ago
[4/4] > Base states are arbitrary things, like a trap or a goal in QMM, but you can still ask what the chances are of a particle being in one of them. You're right that basis states can be arbitrary. However, that's not t
866.
by evanb 10y ago
[3/4] > You could also massively simplify particle interactions to make some reasonable gameplay; perhaps even simulate a quantum computer. Do get in touch with me if you want to do this; I’d be keen to help. If you can find a way t
867.
by evanb 10y ago
[2/4] > Decoherence doesn’t explain, though, why the wavefunction collapses to a singular thing we call “reality”. So quantum mysticism still has room to flourish. No. Decoherence is the thing that lets you avoid the need to colla
868.
by evanb 10y ago
[1/4] Source: I am a nuclear physicist. Full disclosure: I didn't play. I'm not launching a Java applet. So I'm just reading your description for physics content. > (The independence of quantum systems from absolute
869.
by evanb 10y ago
The Gravity Research Foundation's essay contest is one of the most well-known and prestigious essay contests in physics, in which authors are encouraged to synthesize and simplify their technical work into a short, approachable-for-phy
870.
by evanb 11y ago
In Lattice QCD [1] we basically execute huge MCMC in order to sample the partition function [2] on a discretized spacetime. [1] https://en.wikipedia.org/wiki/Lattice_QCD [2] https://en.wikipedia.org/wik

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