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  • recently is being a lot of excitement because even Hawkin has claimed he solved the information paradox.

  • So the black hole information paradox.

  • That's sort of a puzzle that's been around for some time now, and it's kind of boils down to the fact that information is lost in a black hole, and that violates everything.

  • The you you think you you believe from quantum mechanics, quantum mechanics, allergy.

  • That's essentially what goes in must come out.

  • Physics is what we call unitary, so information shouldn't be lost in the system.

  • So it so, for example, why would information we lost in a black hole?

  • Why don't Why do people believe this?

  • We'll take a take a black hole on, throw something.

  • So what could you throw in a while?

  • You could throw Gary Neville in it.

  • Now what happens?

  • Well, all that happens when they eventually the black hole will.

  • Its mass will increase a little bit of the results of Gary being thrown in its charge.

  • Might change of Gary carrying charge if you carried angular momentum is angular.

  • Momentum may change, but nothing else.

  • That's it.

  • So where did all the information go about his his his face is tattoos at all this?

  • Where did all that go?

  • Okay, it's just the same black.

  • Also, I could also throw in Donald Trump.

  • Okay?

  • Instead, right on time.

  • I end up with exactly a very different information.

  • For example, you know, he's got funny hair is obnoxious personality or all these things I could throw him in, but I end up with the same black hole.

  • Well, what I'm saying it So you can't say OK can extract the information back so black hole will eventually radiate eventually give off a type of radiation called hawking radiation.

  • Right now, this is what you get when you apply quantum mechanics to the event horizon of a black hole.

  • It gives off this hawking radiator so you can extract that information about whether it was Gary I threw into a black hole or Donald Trump from the Hawking radiation and naive.

  • You think?

  • Well, absolutely no, because the object that it came from only knows about Nash charge and angle momentum.

  • It's This is a saying that black holes have no hair.

  • Okay, They all only information they contain of this mass charge and angular momentum.

  • So the information seems to have become lost.

  • Tony wise this explosive Two black holes, though.

  • I mean, if those two people died and decomposed in the ground would have that information also be lost.

  • No, no, no, no.

  • That that made you want to be lost there.

  • So the decomposing the ground.

  • But you could extract that information you could, you know, from the whatever remains were left, you could work back and work out.

  • It might be difficult, but you could do it in print, but with a black hole, all the calculators the organ did pointed to the suggestion that this couldn't happen.

  • Okay, that the information is truly lost.

  • That completely seems to violate one of the things you hold sacred about quantum mechanics.

  • So it's a huge.

  • It was a huge issue.

  • So for years, people have been trying to resolve this and his various ideas put forward.

  • Maybe the black hole doesn't completely evaporate away.

  • Okay, On its left with some remnant which contains a lot of information, contains all the information about how the black hole was formed.

  • Right?

  • But that doesn't quite work either, because if you throw one of these black hole remnants into a black hole.

  • It's another black hole.

  • You violate things like the second law of thermodynamics.

  • It just doesn't quite work.

  • There's other proposals that people have put forward.

  • For example, baby universes.

  • That is one thing that Hawking liked that on the other side of the black hole there's a baby universe, and somehow the information leaks into their again.

  • That's based on ideas, which didn't just quite pan out in the mid nineties.

  • People realised that actually, black holes probably don't lose information because something came along called the Holographic Principle.

  • But still people haven't understood how it really is.

  • Where the information Where is it?

  • Still it still not fully understood until these recent claims by Hawking and his collaborators.

  • There isn't paper out about this, so I'm kind of winging it a little bit.

  • And there have been some seminars and particular by Hawking in Stockholm.

  • But that was only a short nine minutes seminar here.

  • One of his collaborators, Malcolm Perry's being given talks about this.

  • Also, Andy Strominger, who's the other collaborator.

  • You sometimes give talks about stuff that's not quite completed yet.

  • I've done it before as well, maybe not something spectacular is this for anyway.

  • But it s so what?

  • What they're saying is really quite interesting at least what I'm trying to glean from from what they're saying.

  • As I said, all the details aren't out yet, but it sends out.

  • We've saying black holes have no hair, but actually turns out they seem to have a lot more were able to contain a lot more information.

  • And we previously realized they have an infinite amount.

  • So Buckle have has no hair, is just the statement, right?

  • Black holes don't know about Donald Trump's Donald Trump's hair.

  • I don't know about that hair.

  • So why did when they were coming up with saying, Why did they choose hair, black clothes?

  • You have to.

  • I guess it's sort of a very smooth object, something of the idea.

  • But now they do have here.

  • Well, it seems so.

  • I mean, this is not completely non trivial, trivial thing, and it all goes back to something that guys called bonding.

  • Metzner and Sachs did.

  • They were.

  • They were thinking about the effects of gravitational radiation on things like that, and they discovered that there was actually a much larger class of symmetries called BMS image cheese and particularly including something called Super Translations.

  • And there's an even amount of these things.

  • Hey, now, what Hawking realized was that these things also exist on a black hole event horizon.

  • And so that is where the information being starts.

  • When something falls into the black hole of any arise and it causes a super translation changes the charge there.

  • And in principle, you could store in Infinite.

  • But there's an infinite amount possible charges, and this seems to be where the information's going.

  • So we're going mobile Force into a black hole.

  • It changes the one of these, let's call it a BMX charges What's called it changed one of these bare mess charges on the horizon.

  • And then what do to calculation That guy called Paul Tyminski did Hawkins suggesting that actually, this can now effect the stuff that's getting admitted.

  • So when when the black hole starts to radiate this change in a big mess, charge this super translation can.

  • It can affect the time at which the photos not say something submitted from the from the black hole, and so that information is now gets stored in this sort of times and slight delays in the times that starts getting admitted.

  • Now he's also saying that it's it's completely scrambled.

  • The information is there, but it's chaotic.

  • So for all practical purposes, you you would never really be able to extract the information.

  • But the claim is, actually, it is there.

  • So it's not lost.

  • It's just very hard to get.

  • So it's like anything that goes into a black hole at the event horizon has like a final Sophie.

  • Yeah, but this is really hard to see and read back.

  • That's one way of putting it.

  • Yeah, yeah, BMS selfie.

  • Yeah, that's kind of and super Cell because these are super translations.

  • Yeah, it's kind of it's kind of nice way for that what the super translations are.

  • So if you imagine this, this surface, this this future Nall infinity.

  • It's a light like surface.

  • You have to be traveling at speed of light to sit on it.

recently is being a lot of excitement because even Hawkin has claimed he solved the information paradox.

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毛茸茸的黑洞和超級自拍--60個符號 (Hairy Black Holes and Super Selfies - Sixty Symbols)

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    林宜悉 發佈於 2021 年 01 月 14 日
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