Lightnews — Scholar-powered news

Rochelle

@uberwensch.bsky.social

1.2K followers 420 following 5.4K posts

like if Just Some Guy was a girl

Posts Media Videos Starter Packs

Pinned

Rochelle @uberwensch.bsky.social · May 7

What is entanglement? Itamar Pittowsky claimed that these results brought us right to the precipice of logical contradiction--but not over. Abner Shimoney described it as a piece of "experimental metaphysics." I'm a nobody, but I think entanglement is the most interesting thing ever discovered.

🧵⚛️

Rochelle @uberwensch.bsky.social · 7h

I feel like PH doesn't explain, but I could be convinced. It seemingly reduces our postulates, in that you don't have to re-explain every instance of gas diffusion. Like how "a body continues in its state of motion" relieves of us explaining why a stone keeps its imparted velocity after being thrown

Rochelle @uberwensch.bsky.social · 7h

I felt it didn't matter where we put it, but clearly it does—esp if it doesn't amount to a complete state specification—at least at the level of "explanatory purchase"; since it will be easier to articulate what the constraint *is* at certain times than at other times (in our case, at early times).

Rochelle @uberwensch.bsky.social · 7h

Hmm... very good analogy.

I think I've conflated two issues here. One is whether boundary condition can be explanatory, and the other is whether it matters where we put it.

Rochelle @uberwensch.bsky.social · 7h

it has some vibes in common with discussions I've had over the experience machine.

Rochelle @uberwensch.bsky.social · 8h

sorry, i got lost in what i was saying and i think it only tangentially responded to your point:

i don't see why it is not highly contingent that we observe only hot suns radiating into cold space, as opposed to a pathwork universe of equilibration and disequilibration.

Rochelle @uberwensch.bsky.social · 8h

Now maybe it is possible that the Past Hypothesis should be regarded as explanatory. Thats what Ken was arguing elsewhere.

Rochelle @uberwensch.bsky.social · 8h

If tendency to equilibrate is supposed to underwrite the flow of time & causality, then: we must necessary be just as surprised that a universe begins out of equilibrium as we would be were an equilibrated universed to move spontaneously towards order.

Rochelle @uberwensch.bsky.social · 8h

But anyway, surely it is not hard to imagine universes that are completely equilibrated at all times, and surely these should dominate under any reasonable measure

Rochelle @uberwensch.bsky.social · 8h

You can pursue the idea that we shouldn't think of each new gas we meet as an independent trial of some theory, because everything ultimately has a common history, and this is getting toward the past hypothesis

Rochelle @uberwensch.bsky.social · 8h

The time-reversal symmetry of fundamental physics suggests that every time we meet a new gas, if we think of it as an independent model/sample of that theory, we should expect equal odds for it to be equilibrating/disequilibrating.

Rochelle @uberwensch.bsky.social · 8h

What I have in mind is the minus-first law of thermodynamics, that all systems left alone will equilibrate. I find it extremely hard to believe that "most" universes have all if their various pockets always co-equilibrating toward the same future.

Rochelle @uberwensch.bsky.social · 10h

oh i thought there was an extra 10^ in there

Rochelle @uberwensch.bsky.social · 10h

isn't "large number" 10^11 in this case?

Rochelle @uberwensch.bsky.social · 10h

i guess it requires you to store more and more digits of pi?

Rochelle @uberwensch.bsky.social · 11h

@kenwharton.bsky.social might have different ideas than me about this

Rochelle @uberwensch.bsky.social · 11h

its just wild

i am somewhat tall myself (for a woman) but you are like 6" taller

Rochelle @uberwensch.bsky.social · 12h

wtf man holy shit

Rochelle @uberwensch.bsky.social · 12h

how tall are you

Reposted by Rochelle

ellie lockhart (she/they) @eleanor.lockhart.contact · 13h

I should stop posting, but I'm not okay

like, being reminded that it is considered rude to express that you were traumatized by your childhood really fucks you up as a child abuse victim

Rochelle @uberwensch.bsky.social · 13h

yet another theorem that requires dim(H) > 2

one begins to wonder why ever theorem hates dimension 2

Rochelle @uberwensch.bsky.social · 13h

Yeah the first one sounds like a similar theorem of von Neumann's and the second one (for commuting operators only) sounds like Kochen-Spekker

Rochelle @uberwensch.bsky.social · 14h

right, although I believe this loophole closes if you assume that spacetime is isotropic & homogeneous. for the precise content of that claim you could see Levy-Lablond's derivation of the Lorentz group, in which he calls upon this assumption (in mathematical form) at a few key steps:

web.physics.utah.edu

Rochelle @uberwensch.bsky.social · 14h

right! this is what I landed on

Rochelle @uberwensch.bsky.social · 14h

How so?

Rochelle @uberwensch.bsky.social · 14h

I feel like @mikebenchcapon.bsky.social made a really nice point about this back on twitter but i just cannot remember what it was