Talks to Watch

Why Quantum Information is Never Destroyed

716K views · May 23, 2018 · 13:43 · 2 HN recommenders · 3 mentions · discussed 2019–2021

A PBS Space Time episode asking whether the universe's information can ever truly be lost, tying quantum mechanics, determinism and black holes together. It sets up the black hole information paradox.

Why Hacker News points people here: HN commenters point to it as an accessible explanation of abstract modern physics around the black hole information problem.

“I have to recommend the relevant PBS Space Time on the subject”HN comment, 2021

What Hacker News said 3

RecommendstzsMay 2021

“I'd recommend the two episodes released right before the one about the black hole information paradox too.”

Sets up the information paradox episode.

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I'd recommend the two episodes released right before the one about the black hole information paradox too. They set up for what is covered in the information paradox episode. "Why Quantum Information is Never Destroyed" - this video "What Survives Inside A Black Hole?" - link Maybe the episode before those two also. I vaguely recall that something from the information paradox episode used something from that (and if I'm misremembering, it was still a neat episode): "Noether's Theorem and The Symmetries of Reality" - link I have a question about the episodes you cited. They cover how beyond the event horizon space becomes time and time becomes space. They go over how that means that inside you can't go backwards in space for the same reason that out here in the normal universe you can't go backwards in time. You are doomed to only go forward, which inside means toward the singularity. (Much better than the ridiculous analogy often given that you can't get out of a black hole because the escape velocity equals or exceeds the speed of light. That's a ridiculous analogy because it only explains why you can't get out ballistically). But all their explanations used a simplified black hole in a spacetime with just 1 space dimension and 1 time dimension. We've actually got 3 space dimension. Does that mean that in a real block hole past the event horizon, you end up in a spacetime with 3 time dimensions and 1 space dimension? If so, does anything interesting happen due to having mor

in “Physicists identify the engine powering black hole energy beams” · view on HN
Recommendsf154hfdsAug 2021

“I have to recommend the relevant PBS Space Time on the subject”

Accessible explanation of abstract modern physics.

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For those of you like me having trouble with the abstract nature of modern physics, I have to recommend the relevant PBS Space Time on the subject: this video

in “Physicist discovered an escape from Hawking’s black hole paradox” · view on HN
Cites itwesturnerAug 2019
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"Why Quantum Information is Never Destroyed" re: determinism and T-Symmetry ("time-reversal symmetry") by PBS SpaceTime this video Classical information is 'collapsed' quantum information, so that would mean that classical information is never lost either. There appear to be multiple solutions for Navier-Stokes; i.e. somewhat chaotic. If white holes are on the other side of black holes, Hawking radiation would not account for the entirety of the collected energy/information. Is our visible universe within a white hole? Is everything that's ever been embedded in the sidewall of a black hole shredder? Maybe even recordings of dinosaurs walking; or is that lemurs walking in reverse? Do 1/n, 1/∞, and n/∞ approach a symbolic limit where scalars should not be discarded; with piecewise operators?

in “How do black holes destroy information and why is that a problem?” · view on HN