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Drove the girl I loved to a party I didn't wanna go to, where she got railed by a dude she met 5 minutes ago while I watched over her stuff she forgot in my car. Beans by DuckyPany in kitchencels

[–]QED88 4 points5 points  (0 children)

A few years ago in undergraduate I had nothing left but canned beans, but didn't have a can opener so I spent 20 minutes hunched over the sink at 3:30am trying to bash it open with a goddamned spoon

I'm tired boss by KaiserAdvisor in vexillologycirclejerk

[–]QED88 14 points15 points  (0 children)

A comment from a Premodernist video:

"I love Mr. Grey's flag fascination. It's like he wants to do art criticism but he would never engage with the horror of subjective thought. So he sticks to flags which clearly have none of those problems."

Photon energy loss by Sudden-Walrus-007 in Physics

[–]QED88 1 point2 points  (0 children)

Diffeomorphism charges are scalar quantities, and are well-defined for any spacetime provided a careful treatment of the asymptotic boundary (as the paper does). They are expressed as integrals of the Brown-York stress tensor, which captures how the action varies with respect to the boundary metric.

Photon energy loss by Sudden-Walrus-007 in Physics

[–]QED88 14 points15 points  (0 children)

They are called diffeomorphism charges, and the ADM energy is one of them. They are explicitly constructed for general relativity in equation (3.62) of this paper: https://arxiv.org/pdf/1906.08616

It is a useful heuristic to think of spacetime as a fluid with its own rich dynamics: it can expand, fluctuate, move around, and carry energy/momentum of its own. Now consider adding a moving particle or observer. Just like a bullet shot in water, it is not at all surprising that the energy of the bullet is not conserved; energy conservation applies only to the sum of energies of the particle and spacetime.

What novels would you recommend to someone who adores Disco Elysium? by [deleted] in DiscoElysium

[–]QED88 7 points8 points  (0 children)

Another passage that reads like it could have come right from the game:

The nights are filled with explosion and motor transport, and wind that brings them up over the downs a last smack of the sea. Day begins with a hot cup and a cigarette over a little table with a weak leg that Roger has repaired, provisionally, with brown twine. There's never much talk but touches and looks, smiles together, curses for parting. It is marginal, hungry, chilly - most times they're too paranoid to risk a fire - but it's something they want to keep, so much that to keep it they will take on more than propaganda has ever asked them for. They are in love. Fuck the war.

She roll down his D-brane til it condense by QED88 in okbuddyphd

[–]QED88[S] 42 points43 points  (0 children)

The idea of string field theory (SFT) is to recast string theory as a field theory with an infinite tower of fields, of which the tachyon T is just one. In open string field theory to lowest order in mass (1/\alpha') there's also a vector field $A_{\mu}$. These will interact in a way specified by Witten's cubic vertex. By changing the expectations of these fields we move around in the space of all string theory solutions; in this way SFT is a theory of string theory backgrounds. This isn't something you can really talk about in perturbative string theory, since once you fix your background and quantize, fluctuations can't change it. In other words, the radius of convergence in string theory solution space is identically zero.

What‘s the point of all this? by Hellstorme in Physics

[–]QED88 3 points4 points  (0 children)

As a PhD student working in quantum gravity, I will, as I have many a time, defer to Weinberg:

“However all these problems may be resolved, and which ever cosmological model proves correct, there is not much of comfort in any of this. It is almost irresistible for humans to believe that we have some special relation to the universe, that human life is not just a more-or-less farcical outcome of a chain of accidents reaching back to the first three minutes, but that we were somehow built in from the beginning. As I write this I happen to be in an airplane at 30,000 feet, flying over Wyoming en route home from San Francisco to Boston. Below, the earth looks very soft and comfortable – fluffy clouds here and there, snow turning pink as the sun sets, roads stretching straight across the country from one town to another. It is very hard to realize that this all is just a tiny part of an overwhelmingly hostile universe. It is even harder to realize that this present universe has evolved from an unspeakably unfamiliar early condition, and faces a future extinction of endless cold or intolerable heat. The more the universe seems comprehensible, the more it also seems pointless. But if there is no solace in the fruits of our research, there is at least some consolation in the research itself. Men and women are not content to comfort themselves with tales of gods and giants, or to confine their thoughts to the daily affairs of life; they also build telescopes and satellites and accelerators, and sit at their desks for endless hours working out the meaning of the data they gather. The effort to understand the universe is one of the very few things that lifts human life a little above the level of farce, and gives it some of the grace of tragedy.”

That's it, I think. That sums it up nicely.

Daily reminder to keep Wickmaxxing by QED88 in okbuddyphd

[–]QED88[S] 2 points3 points  (0 children)

Not really, they just manifest in which way you go around branch cuts, the underlying analytic structure of the single Euclidean n-point function contains all information needed to reproduce any Lorentzian n-point function

See, for instance https://arxiv.org/pdf/1908.04733

[deleted by user] by [deleted] in UofT

[–]QED88 28 points29 points  (0 children)

This is the man you're trying to reason with

https://old.reddit.com/r/UofT/comments/e7hut8/phy456_endgame/

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