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  • they've announced to special prizes from the Fundamental Physics Foundation, a special prize.

  • That's from Buy a Guy, a Russian billionaire called Yuri Milner.

  • The amount of money that's awarded for these prizes is basically the large amount of money that's ever awarded for a physics prize.

  • It's a $3 million so that completely divorce what the Nobel Prize winners gets or Templeton Prize winners.

  • They've announced to special prizes today, one to Stephen Hawking on the other two s seven San physicists.

  • It's a committee that basically decides who's gonna get the prize for the subsequent year, and that's made up of previous prize winners.

  • So there's a bunch of people that got it in the summer, and they they basically they got together and they've decided.

  • But who's gonna get the prize next year?

  • What they've decided, who's going to be nominated?

  • But also they're allowed to make a little special recommendation and say, in cases where it's not part of the main price.

  • But they just decide that somebody's deserves a special price, and it's for the same amount of money on dhe.

  • That's the those of the announcements that were being made today, along with nominations for next year's prize.

  • Well saying, obviously speaks for itself.

  • What what they've achieved at the late see Hawking while Well, we've all heard of him.

  • He's one of the most famous physicist alive today, if not the most famous.

  • But specifically he's won the prize for his contributions to black hole physics on dirt and quantum gravity so academically, clearly he deserves it.

  • Back in the sixties and 70 Talking did some fantastic work, and it's completely revolutionised how even how we understand black holes and, similarly, his ideas about quantum gravity in the universe.

  • It's really important.

  • I do think that the prize itself $3 million Hawking doesn't really need that money.

  • Actually, he's a millionaire anyway, and sometimes you know somebody's gonna throw this amount of money as Milner is a physics then I would probably prefer he was spread out more evenly, and it was used to fund younger researchers rather than just given a putt on the back to the really famous guys.

  • I suppose there is an argument which says that it raises the profile of physics, and that's got to be a good thing as well, but certainly from an academic point of view, I think talking is a worthy recipients.

  • So Hawking basically has had three main scientific achievements in his in his in his career.

  • So the first of these is his singularity fair rooms.

  • So what hawking and on Roger Penrose realized is that if you issue matter has some generic properties that are very every type of batter, sensible type of matter that we see in nature has the new comm prove that singularities exist within Einstein's theory of relativity?

  • So a singularity is, is a region of infinite density, an infinite space time curvature where all your field equations break down.

  • What they're telling us here is that Einstein's theory actually has its limitations, that it predicts its own downfall.

  • The second thing, another place where you get these similarities, of course, is is in black holes at the center of a black hole of star collapses, and it forms one of these objects.

  • People often say black holes at a black that literally no light can escape because the gravitational field is so strong.

  • But what Hawking realized and this is probably his greatest achievement was that when you apply quantum mechanics, particularly to the event horizon of a black hole that you can get particle creation on sort of either side of the event horizon.

  • So you have, Ah, Paschal and anti particle literally pop into existence.

  • So the particle escapes and the anti particle falls into the black hole.

  • And this process allows a black hole to actually radiate.

  • Actually give off radiation, which, as you said, it's hawking radiation on the black hole will.

  • Actually, you know it can radiate away as a result of this process.

  • Although we still don't understand the end points of that that evaporation process, we know that it will radiate, radiate, radiate but worms at the end.

  • Actually, when it gets a very small plank inside a black hole way don't really know what happens there.

  • Tell your four black holes have never actually been observed.

  • So how do we know hawking radiation is correct?

  • So we don't know hawking radiation is correct, but this is one of the points of the price so that there is no experimental proof of hawking radiation, and it's possible that we might produce a black hole at the L A.

  • C.

  • And if we did then that could that we've detected hawking radiation.

  • That's how we would know it was there on.

  • Then we'd say, OK, right.

  • Give Hawking overpriced.

  • Maybe some other people, too, for related work.

  • But there's no proof of this at the moment.

  • And certainly you ain't gonna detect the hawking radiation from the black hole at the center of the galaxy.

  • If there is one that So the question is household, you never gonna get a prize for this remarkable work?

  • Well, this is the point of this prize that I think nowadays, theoretical physics has event so much.

  • And the gap between theory and experiments in terms of time scale is so large that I will be surprised if, after the after the discovery of the Higgs, that any theorist will get a Nobel Prize again.

  • Certainly in this area of cosmology, quantum gravity, simply because the gap between theory and experiment is coming so large.

  • So that's one of the good things about this prize.

  • It fills that gap.

  • It doesn't demand that there has to be experimental proof.

  • It's just that the community itself has accepted that black holes will give off hawking radiation.

  • So the third discovery of hawking or I say I I'm loath to say discovery because these these air not proven is these things yet, but they're great ideas on.

  • The third thing that Hawking introduced was the idea of the way function of the universe.

  • In quantum mechanics, everything is described by wave functions, so you don't have any sort of definite state anymore.

  • Everything's just a mixture of different possible scenarios.

  • Hawkin applied this idea to the universe, and in particular he's being able to do away with the singularity at the beginning of the universe.

  • And what he did was he advocates, Well, it's in it.

  • Look here, What's called Euclidean Quantum Gravity.

  • This is a pretty heavy going book, and I know that some of hawking students have to read this before they do anything else.

  • I have to read through the whole book.

  • You collecting the Euclidean bit of that means you go to imaginary time so you get rid of in real time and you go to imaginary time described physics like that and what that does is you can have a scenario where when you go back in imaginary time, the the universe just closes off.

  • You have no boundary so there's no initial point in time.

  • You can't define that.

  • It just closes off when you say imaginary time.

  • Do you mean like a time where there's Cinderella or do you mean imaginary in terms of I A number that doesn't exist?

  • No.

  • But it doesn't exist.

  • Yeah, I need the insides of the imaginary number yet exactly.

  • So you would basically you go from time, as in real time to I times that you can have an entire process which would happen instantaneously in real time.

  • But actually, when you go to imaginary, it's actually moving around an imaginary time.

  • This process is happening in imaginary time, so that's where it's going on.

  • And you can actually make predictions that that can be verified based on all this little dynamics, but in the imaginary time plane, if you like, So you actually owe you some ideas.

  • You could even go to complex time, but you have a real component, an imaginary component.

  • I mean, you can really extend the notion of time in this way.

  • One of the things that Hawking's don't recently where he's applied these ideas of Euclidean quantum gravity to is, is to the acceleration of the universe.

  • So we know that the universe is expanding quicker and quicker today.

  • And normally we attribute that to a positive cosmological constant of positive energy of the vacuum.

  • Now what Hawking is claiming is that actually, you can get the same effect, but from a negative cosmological, constant and negative energy of the vacuum.

  • Now that doesn't normally happen, right?

  • That's not what normally happens.

  • Negative cosmological constant behaves very, very differently.

  • Typically, the universe would just crunch.

  • But he's saying, actually, you can get this cosmic acceleration out of it, and that's really weird.

  • Well, I know that he does his calculations in his head, which I just find.

  • It's just astonishing, absolutely astonishing.

  • I mean, I got to be a pilot here.

  • Just they're just calculations by.

  • This is a 15 page calculation.

  • Hazel's on his head.

  • It's unbelievable.

  • I just find it astonishing.

  • So So hawking, obviously you know, is this this great guy and astonishing physicists that a friend of mine was behind him in the queue for tea.

  • Once in Cambridge.

  • Stephen Hawking in front of me and the kid.

  • That's pretty pretty cool, isn't it?

  • I wonder what he's gonna say thinking Cor can get to the front of the queue and these He's off.

  • He's going to say something on there.

  • And then he said them tea, please.

  • So that was all of it disappointing for, I don't know, I expected some sort of dramatic incited, you know, the physics of tea or something that you just got tea, please.

  • It is a normal fastened as well.

  • I think it's the point.

they've announced to special prizes from the Fundamental Physics Foundation, a special prize.

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為什麼霍金是個大人物?- 六十個符號 (Why is Stephen Hawking a big deal? - Sixty Symbols)

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    林宜悉 發佈於 2021 年 01 月 14 日
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