Can Black Holes Unify General Relativity & Quantum Mechanics?

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Black holes are inevitable predictions of general relativity—our best theory of space, time and gravity. But they clash in multiple ways with quantum mechanics, our equally successful description of the subatomic world. One such clash is the black hole information paradox—and a proposed solution—black hole complementarity—may forced us to radically rethink what it even means to say that something to exists.

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini & Stephanie Faria
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Assistant Director of Programming for PBS: John Campbell

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[jonathancrowder]

The devs adding in a firewall plugin to stop dupe exploits is very on brand with our universe

[Zaznin]

I like that this basically seems to boil down to, "it's not a crime if you don't get caught." Just on a universal scale.

[Paul-A]

Babies without object permanence: if I can't see it It doesn't exist
Physicists: Maybe you're right!

[subcitizen]

I listened to Susskind's lectures many times. If you put an iPhone into a blender, an iPhone still comes out, even if it's not an iPhone anymore. At least technically speaking, per the math, it's very possible that there's no violations. For our reference frame as observers though, we lose Alice, the qubit, and the iPhone. But we do get to keep the free blender.

[DarkPesco]

Poor Alice and Bob! But still...WHAT A WAY TO GO!!!

[bnightm]

This description of black hole complementarity reminded me of superposition. A sort of simultaneous existence that is "allowed" by the impossibility of observing more than one outcome.

[BenWard]

People are going nuts about Terrance Howard right now. I’ve spent the last 2 hours arguing with people in the comments of his videos about why he’s clueless about physics. He’s brining in a lot of people to gobbledygook with his charisma. I had to watch this video like 4 times to make me feel better again. Thanks Matt! I would love to see a video on pseudoscience or Terryology from you- I know that’s not your game normally but it’s really bad out there right now.

[eragonawesome]

It seems like Horizons in general represent a much more fundamental mechanism than people give them credit for. Based on the Unruh effect and black hole complementarity, it seems like one could reasonably say that beyond any horizon is effectively not a part of the same universe anymore.

[WhydoIsuddenlyhaveahandle]

That scene in Spaceballs with Colonel Sanders and Dark Helmet about "Now" was always hilarious to me.

The more I learn about Relativity, I realize that scene is actually scientific haha

[ScarecrowB]

Has it ever been difficult to create the 'space-time' bit at the end of each episode? It's always done so well.

[pablolara]

I don’t even remember subscribing to this channel, but I’m glad I did. Will pay more attention to it from now on.

Funnily enough, today I was listening to Sean Carroll interview Leonard Suskind in his podcast.

[crystalAegis]

perfect! literally just finished watching the previous episode, went "well DARN I want to learn about this more!" and BAM you upload the next episode! Always lovely for a coincidence like that to happen!! (I even looked up Black Hole Complementarity)

[fhvisuals]

Alice and Bob, the favorite guinea pigs in theoretical physics.

[Endofnames]

What ever happened to comment reads/responses? That was one of my favorite parts.

[NewMessage]

Alice and Bob are built different, man.

[cipcervantes]

That firewall is interesting. We gotta exploit that

[nithinsuku]

Just as I was rewatching PBS Space-Time videos, you dropped a new one! 😊

[Graycy]

Spacetime was the first channel I subscribed to on utube and actually watched daily till I'd binged all the vids. I look forward to every release and still binge on the old stuff in between. I think if I listen enough I'll have no choice but to understand quantum physics having learned by pure absorption and exposure lol!

[ntthemessiah]

It feels like the explanation of BHC implies it wouldn't only apply to black holes and the spaces outside them, but also to any regions of space which can no longer be causally linked. For instance, two galaxies that drift so far apart the light from one would never reach the other. There doesn't appear to be any functional difference between these pictures. Am I missing something? Because the implications of this are kind of wacky.

[glennscott]

This one will have to get watched multiple times. Appreciate your work and keeping this a higher level discourse. 🙏