Spaghettification Mysteries, Neutron Stars vs. Black Holes & The Wormhole Debate

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Andrew Dunkley: Hi again, Andrew Dunkley here. And, uh,

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thanks for joining us, uh, on Space Nuts Q

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and A edition. And coming up, we've got

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questions from Buddy about spaghettification,

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and I'm pretty sure he's not talking about an

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Italian restaurant. Uh, we're also looking at

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news. Neutron stars versus black holes. I

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think we've had similar questions in the

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past, but it keeps coming up. Uh, we're

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also looking at wormholes. And,

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uh, somebody has a pre Big Bang

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theory which we'd like to discuss. We'll talk

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about all of that on this episode of Space

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Nuts. 15 seconds.

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Generic: Guidance is internal. 10,

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9. Ignition sequence start.

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Jonti Horner: Space Nuts. 5, 4, 3, 2.

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Generic: 1, 2, 3, 4, 5, 5, 4, 3,

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2, 1.

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Jonti Horner: Space Nuts astronauts report it feels

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good.

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Andrew Dunkley: And I do love the Q and A edition because,

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um, somebody else other than us sets the

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agenda. The downside is we have to think.

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And joining me now is Jonti, uh, Horner,

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professor of Astrophysics at the University

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of Southern Queensland. Jonti, hello again.

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Jonti Horner: Hello again. Good afternoon. Good evening.

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Andrew Dunkley: Good to see you. Got, um, some interesting

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questions today. Do you want to get straight

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into it?

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Jonti Horner: Yes, can do. And I will give the usual caveat

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right at the start of this. I'm quite happy

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to admit my ignorance to a lot of this. Um, I

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am not a cosmologist, so this is pushing

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the boundaries of my knowledge to places that

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it has never gone m before. And I'll do my

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very best, but my apologies, other answers

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are available. And you know, there's a film

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critic in the UK who often says other

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opinions are available. They're wrong, but

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they're available. Um, in the case of this

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one, it may well be that other answers are

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available and they are more likely to be

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right than mine. But I will do my best.

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Andrew Dunkley: Fred often throws in the same caveat, so it's

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all good.

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Uh, our first question today comes from a

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regular contributor. His name is Buddy.

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Generic: Hello, space. This is Buddy from Ontario,

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Oregon. Hey, um, I got a

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question about spaghettification. Is it an

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illusion or is it a. Is it real?

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Is it. Is it just, uh, a distortion of

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our eyes to the fourth dimension? Or are

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things actually being stretched? And

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on that same page, they say that photons

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and photonic particles act like a wave and a,

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uh, particle at the same time. Is that what

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makes it a wave? Maybe. Is that a form of

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spaghettification? Maybe. All

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right, thanks, guys. Love your podcast.

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Andrew Dunkley: Thank you, Buddy. Buddy's always thinking. I

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can hear his mind from halfway across the

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planet, just tumbling and tumbling, trying to

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figure out all this Stuff because he comes up

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with so many interesting questions.

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Spaghettification, uh, first part of his

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question is, is it an illusion? Or, you

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know, if you were there, would you get

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spaghettified good and proper?

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Jonti Horner: It's a really good question. And that thing

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of constantly thinking, constantly

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questioning everything is fundamentally what

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science is. We find things we don't

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understand and we come up with ideas to

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explain them and try and figure it out. And

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there's always more to learn. So that's

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fabulous. In terms of spaghettification, the

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idea here is that if you were to fall into a

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black hole, it would not be pleasant and

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you would be stretched out gradually so

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that you got stretched out like spaghetti.

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And it would be a very painful and unpleasant

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death. Um, from the point of view of the

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observer looking down from above, it would

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also be a death that takes an incredibly long

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time because there is, as you fall into

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a black hole, the light that's emitted

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is slowed down by gravity. So you get this

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kind of time dilation effect where somebody

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watching you would see your clock tick ever

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slower. So they get to watch your suffering

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in great and slow and painful detail, which

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is wonderful. But the idea behind

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spaghettification comes from the

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fact that if you are falling into

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a black hole and your feet are nearer to the

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black hole than your head is, your feet will

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experience a stronger gravitational pull.

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Now, this is kind of how the tides work on

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Earth, to be honest. It's also how the

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concept of the Roche limit comes about, which

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is where we can work out how close to a

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massive object like the Earth a smaller

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object can get before it gets torn apart. All

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of these things are built around the same

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idea, which is that, uh, the strength of the

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gravitational pull that you experience

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from a given object falls off

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as one over the distance squared. So the

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further away you are, the weaker the

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gravitational pull is. Now, if you're falling

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into a black hole, that is

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a solar mass black hole, if you

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get a black hole, the mass of the sun,

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it's tiny. We can actually work out

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the radius of that black hole. I've not got

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the number off the top of my head, but it's

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very, very small. It's probably only a few

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meters across, right? A

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neutron star, the mass of the sun will be

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about 2 km. A black hole will be much, much

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smaller. What that means is that if you're

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falling into that when you're getting very,

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very close to it, the difference in

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distance between your feet and your head from

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the middle of that is actually a significant

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fraction of the distance distance that you

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are from it. So if you are 2 kilometers away

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from this thing and you're 2 meters tall,

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then your feet are 1 1000th nearer

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than your head is. And that means that the

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difference in distance leads to a very big

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difference in gravitational pull between your

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feet and your head. So you will get

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stretched, and the closer in you get, the

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more dramatic that gradient is

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in the gravitational pull between your feet

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and your head. Now you might think,

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okay, well, that's fine, I'll just fall in

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lying on my stomach. You'll still have the

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same problem because the difference in

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gravitational pull between your nose and the

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back of your head will be bad. So your nose

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will get stretched out and you look a bit

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like Pinocchio, as would other parts of your

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body be equally stretched out. So you're

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doomed either way. But it is a very

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real thing that would happen. The reason

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that you could probably argue it's an

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illusion is to the best of our knowledge,

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we've never dropped a human into a black hole

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yet. So the only times you see this are in

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thought experiments or in expensive high

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budget Hollywood movies. But the

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physics behind it makes sense. Now, one of

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the quirky outcomes of this is, uh, as you

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increase the mass of a black hole, you'd

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increase its radius, but

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the, um, force

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due to gravity falls off of one over, uh,

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radius squared. So you have this slightly

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bizarre thing that you would get this

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happening if you were falling into a solar

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mass black hole or an earth mass black hole

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hole, if one existed. Supermassive black

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holes, though, are so incredibly big

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that the gradient between your

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feet and your head would be very small when

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you were near the event horizon, and you

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wouldn't get spaghettified. So if you think

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about the supermassive black hole in the

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middle of our galaxy, the radius of that, I

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believe, is wider than the orbit of Neptune,

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30 astronomical units. So if you're near the

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event horizon for a black hole of that size,

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you are something like billions of kilometers

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from the middle. And, uh, the distance

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between your feet and your head is still 2

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meters. So 2 meters out of billions of

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kilometers is a very tiny difference. So

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you wouldn't really be spaghettified. So if

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you wanted to not be spaghettified while

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falling into a black hole, I'd recommend you

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go to the middle of the galaxy. Um, but I

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would personally choose not to fall into a

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black hole, given the choice. So it worked

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out in white To Live.

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Andrew Dunkley: It worked in the movie Interstellar. They

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managed to get into one, but, um, yeah, that

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was science fiction. Although I do Believe a

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lot of the science they developed

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for that film was, was based on

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actuality. They just augmented it to suit

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themselves.

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But, uh, and the second part of Buddy's

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question was, um, photons,

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uh, can there be a wave and a particle at the

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same time?

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Jonti Horner: Yeah. This is going back to the

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dawn of things like general relativity,

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special relativity, and the dawn of the 20th

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century where you get this wave particle

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duality concept. And it's in

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part based around the observed properties of

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light and how it behaves. And you do

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experiments when you do an undergrad physics

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degree where you reproduce what they did 120

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odd years ago. And, um, you can

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get both kinds of behaviors.

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The famous one is what's called Young's

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double slit experiment. So you've got a light

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source, like the light illuminating me at the

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minute. And, um, you pass that light through

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a wall where there are two very thin slits.

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And then you look down from above and you can

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see the light waves expanding away from

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those two slits and interfering with each

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other because they get diffracted through the

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gap. And you usually illustrate this. I've

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done this before in my undergrad teaching by

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photographs of waves in the ocean passing

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around barriers or passing through gaps. And

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you see the same diffraction thing. So you've

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got short waves coming towards the gap, and

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then they go through two little holes and you

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get circular ripples going out that interfere

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with each other and you get these

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interference patterns.

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Andrew Dunkley: Yeah.

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Jonti Horner: And, uh, that type of behavior is like acting

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as a wave. It's behaving just like waves in

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the ocean do. What you get,

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though, is if you dim your light down, and

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dim it down and dim it down, there's a weird

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quantization effect. That light of a given

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color you can't make

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infinitely faint because you've got a

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certain amount of energy carried by

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photons. And so if you make your

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light dim enough, you can isolate individual

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packets of energy, which is what people

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describe as photons. So if you get a really,

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really, really, really faint light source,

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the photons, and you have them

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that double slit again, the light source

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behind it, light going through the slit and

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then hitting a sensor that measures the

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light, you get individual flashes of light

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where the photons hit. And so the photons

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appear to be moving as packets or particles

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of light, and you get a single flash. If you

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record millions of those flashes, they

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will form that same diffraction pattern.

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So the light is behaving as both

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a particle and a wave at the same time. The

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really bizarre part of this for me, is the

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fact that what this means is that

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from a probability point of view, because you

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get that diffraction pattern, because you get

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those maxima and minima, all the

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interference, what that means is that while

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light is behaving as a particle, it's

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technically going through both slits at once.

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So that particle is in two places at one

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time. And it all gets really, really bizarre.

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Ties into, again, something I was talking

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about in my, um, tutorial today for my

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undergrad students. We were talking about

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something called the Akovsky effect, which

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is to do with light from the

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sun being absorbed by an asteroid and then re

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emitted by that asteroid, and you get a

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transfer of momentum. If the asteroid's

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rotating a little bit, the direction the

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light is emitted is not the same as it goes

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in. And that means you get a little bit of a

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rocket thrust on the asteroid, and that can

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change its orbit on really long periods of

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time. One of my students said, I don't quite

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get this. How can photons, which have no

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mass, have momentum? Because you

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need momentum in order to transfer momentum

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to apply the thrust to the asteroid. So I

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had to look into it then, and it turns out

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that the concept of momentum is

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fundamental to photons. So these packets of

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energy traveling at the speed of light that

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have no mass still have momentum.

290
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And that momentum is entirely contained in

291
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the energy and the oscillation of the

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electromagnetic waves that make up that

293
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packet of energy, that particle. And, uh, it

294
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ends up going back to the famous equation

295
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equals MC squared, which is the

296
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relationship between energy and matter. Now,

297
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equals MC squared is a simplification of a

298
00:11:41.690 --> 00:11:43.770
more complex equation Einstein came up with,

299
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which, off the top of my head, I think it's E

300
00:11:46.010 --> 00:11:48.690
squared equals P squared C

301
00:11:48.690 --> 00:11:51.570
squared plus M m squared C to the

302
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4. So this is the total

303
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energy is proportional, is related to the

304
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momentum times the speed of light, plus

305
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the mass times the speed of light squared. So

306
00:12:02.510 --> 00:12:04.470
if you've got something moving very slowly,

307
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then it simplifies to equals MC squared

308
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because there's not much momentum. But if

309
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you've got something traveling at the speed

310
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of light, the mass is zero. So the MC squared

311
00:12:13.190 --> 00:12:16.190
bit vanishes, and you just get the energy is

312
00:12:16.190 --> 00:12:18.189
equal to the momentum times the speed of

313
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light. So in other words, the momentum of a

314
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photon is equal to the energy of the photon

315
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divided by the speed of light. Which means

316
00:12:26.150 --> 00:12:28.390
that even though photons have no mass,

317
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they still carry momentum, and it's a

318
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fundamental part of them. And what this tells

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00:12:33.320 --> 00:12:34.960
you more than anything else is when you get

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to the quantum scale. Tiny little things.

321
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When you start dealing with relativity,

322
00:12:39.800 --> 00:12:42.200
nothing makes sense. It's not common sense.

323
00:12:42.680 --> 00:12:44.160
And, um, we're still trying to understand it,

324
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and it's all really hard. But all of that is

325
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tied into this wave particle duality and the

326
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Young's double slit experiment. And, um, to

327
00:12:51.800 --> 00:12:53.400
be honest, it makes all our heads hurt.

328
00:12:53.720 --> 00:12:56.280
Andrew Dunkley: Yeah, it does. But great, um, question,

329
00:12:56.280 --> 00:12:57.880
buddy. Thanks for sending it in.

330
00:13:00.410 --> 00:13:02.410
Okay, we checked all four systems, and.

331
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Jonti Horner: Being with a girl, Space Nuts.

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Andrew Dunkley: Uh, our next question. Jonti comes from

333
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istok. Uh, he says hi. I like your

334
00:13:09.530 --> 00:13:12.500
Space Nuts podcast. So do we. Uh, a, ah,

335
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neutron star is very dense as it contains

336
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only neutrons. So no empty

337
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space between the core and electrons. Right.

338
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What happens to the matter at a

339
00:13:23.650 --> 00:13:26.550
black hole? Is there empty space, uh,

340
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also inside neutrons? And can they

341
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be even denser? Thank you. ISTOK

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from Slovenia. We haven't had many questions

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from Slovenia. Nice to hear from you. Um,

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this one, um, I got to confess, is

345
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way out of my ballpark.

346
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Jonti Horner: This is a really, ah, awesome question. And

347
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it's pushing the boundaries of, we don't know

348
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the way all this works. We talked about white

349
00:13:52.190 --> 00:13:54.910
dwarfs earlier. If you compress

350
00:13:54.910 --> 00:13:57.310
matter into a smaller and smaller space, you

351
00:13:57.310 --> 00:13:59.310
can get nuclear fusion happening, propping up

352
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a star. And that's why stars shine. Star,

353
00:14:01.830 --> 00:14:03.550
like the sun, gets to the end of its life,

354
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blows off its outer layers, can't support

355
00:14:05.990 --> 00:14:07.910
itself with nuclear fusion anymore because it

356
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can't get the fusion going. So gravity wins

357
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and collapses everything in. And eventually

358
00:14:13.350 --> 00:14:16.190
you get to a point where atoms are propped up

359
00:14:16.190 --> 00:14:18.270
against each other, held up by something

360
00:14:18.270 --> 00:14:21.140
called electron degeneracy pressure. Um, and

361
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what that is effectively is you've got of a

362
00:14:23.260 --> 00:14:25.420
given atom, as Iztoch's inferring here,

363
00:14:25.420 --> 00:14:27.440
you've got the nucleus in the middle, and,

364
00:14:27.440 --> 00:14:29.420
um, then way, way on the outside, you've got

365
00:14:29.420 --> 00:14:31.340
this cloud of electrons going around it. And

366
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those electrons are negatively charged. And

367
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the analogy people often use here is

368
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something like the nucleus is like a grape at

369
00:14:37.900 --> 00:14:39.820
the middle of a football field, and the

370
00:14:39.820 --> 00:14:41.220
electrons are, like, running around the

371
00:14:41.220 --> 00:14:43.260
boundary. So there's a lot of empty space in

372
00:14:43.260 --> 00:14:45.540
there. Which means if you take the mass of

373
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the sun and compress it down so that

374
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all the atoms are, ah, butted up against each

375
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other, so their electron clouds are pressing

376
00:14:53.410 --> 00:14:54.930
on each other, and you've got rid of all the

377
00:14:54.930 --> 00:14:57.930
space outside the atoms. You get an object

378
00:14:57.930 --> 00:15:00.170
about the size of the Earth. So you take an

379
00:15:00.170 --> 00:15:02.330
object, the mass of the sun, um, squash it to

380
00:15:02.330 --> 00:15:04.570
the size of The Earth. And at that point, the

381
00:15:04.570 --> 00:15:06.770
electron clouds around each atom butt up

382
00:15:06.770 --> 00:15:08.690
against each other, and uh, the negative

383
00:15:08.690 --> 00:15:10.850
charge and the negative charge repel each

384
00:15:10.850 --> 00:15:12.930
other and you get a pressure that holds it

385
00:15:12.930 --> 00:15:15.710
up. That's called electron degenerative

386
00:15:15.710 --> 00:15:18.350
pressure. And that works. And you can keep

387
00:15:18.350 --> 00:15:20.150
adding mass and adding mass, but eventually,

388
00:15:20.150 --> 00:15:22.590
if you get to about 1.4 times the mass of the

389
00:15:22.590 --> 00:15:24.910
sun, a point you call the Chandrasekhar

390
00:15:24.910 --> 00:15:27.910
limit, the gravitational pull is strong

391
00:15:27.910 --> 00:15:29.830
enough to overcome the repulsion of those

392
00:15:29.830 --> 00:15:32.590
electrons, and gravity wins. And so things

393
00:15:32.590 --> 00:15:35.390
keep collapsing further, and that squashes

394
00:15:35.390 --> 00:15:37.350
the electrons and the protons in the atoms

395
00:15:37.350 --> 00:15:40.000
together, making neutrons. And so the atoms

396
00:15:40.000 --> 00:15:42.600
of those, well, m, all those atoms that made

397
00:15:42.600 --> 00:15:45.440
up the white dwarf get turned

398
00:15:45.520 --> 00:15:48.240
into neutrons. And so

399
00:15:48.240 --> 00:15:50.080
suddenly you've gone from a football pitch

400
00:15:50.080 --> 00:15:52.040
size to a grape. Everything's squashed into

401
00:15:52.040 --> 00:15:54.680
the nucleus and everything keeps

402
00:15:54.680 --> 00:15:56.920
collapsing. But eventually neutrons butt up

403
00:15:56.920 --> 00:15:59.280
against each other and the strong nuclear

404
00:15:59.280 --> 00:16:01.920
force I think it is stops them

405
00:16:02.320 --> 00:16:04.000
collapsing any further. There's a new

406
00:16:04.000 --> 00:16:05.920
pressure, which is called neutron degeneracy

407
00:16:05.920 --> 00:16:08.750
pressure, and that holds neutron stars up.

408
00:16:09.390 --> 00:16:12.030
And so you get something the mass of the sun,

409
00:16:12.030 --> 00:16:14.070
but the size of a city a few kilometers

410
00:16:14.070 --> 00:16:16.750
across. Okay, Keep adding mass to that and

411
00:16:16.750 --> 00:16:18.310
you eventually reach critical mass. I've

412
00:16:18.310 --> 00:16:19.750
forgotten the name of it. But the critical

413
00:16:19.750 --> 00:16:21.670
mass for neutron stars is thought to be about

414
00:16:21.670 --> 00:16:24.390
three times the mass of the sun. And at that

415
00:16:24.390 --> 00:16:26.310
point, gravity is strong enough that the

416
00:16:26.310 --> 00:16:28.950
strength of the neutrons pushing apart cannot

417
00:16:28.950 --> 00:16:30.590
hold them up against gravity, and gravity

418
00:16:30.590 --> 00:16:33.480
wins. So things collapse down

419
00:16:33.480 --> 00:16:35.400
even further. And this is where it gets to

420
00:16:35.640 --> 00:16:37.600
the point of our understanding starting to

421
00:16:37.600 --> 00:16:40.600
fail. There are some suggestions that if

422
00:16:40.600 --> 00:16:42.520
you squash neutrons together with enough

423
00:16:42.520 --> 00:16:45.280
force, you can compress them down

424
00:16:45.280 --> 00:16:48.280
so that inside, inside that neutron,

425
00:16:48.280 --> 00:16:50.000
you've got a lot of empty space and some

426
00:16:50.000 --> 00:16:53.000
subatomic particles, quarks. And you could

427
00:16:53.000 --> 00:16:55.280
squash them together until the force between

428
00:16:55.280 --> 00:16:57.960
the quarks prevents them

429
00:16:57.960 --> 00:16:59.600
squashing in. Any further. And you could get

430
00:16:59.600 --> 00:17:01.080
an additional kind of thing, which is why you

431
00:17:01.080 --> 00:17:03.690
get the concept of a quark star. And some

432
00:17:03.690 --> 00:17:05.650
people have speculated that within quarks

433
00:17:05.650 --> 00:17:07.570
you've maybe got sub subatomic particles,

434
00:17:07.570 --> 00:17:09.770
which I think are called pions or P Os or

435
00:17:09.770 --> 00:17:12.130
something like this. So maybe after a quarks

436
00:17:12.130 --> 00:17:13.490
are, you can get smaller still.

437
00:17:14.450 --> 00:17:17.010
Fundamentally though, every time

438
00:17:17.170 --> 00:17:19.850
mass scale, you'll reach a point where no

439
00:17:19.850 --> 00:17:21.570
force we can imagine is strong enough to hold

440
00:17:21.570 --> 00:17:24.210
it up and it'll collapse further. What you

441
00:17:24.210 --> 00:17:27.170
get with a black hole is secondary

442
00:17:27.170 --> 00:17:29.520
to this. It's kind of separate to it, which

443
00:17:29.520 --> 00:17:32.240
is that the amount of mass you've got

444
00:17:32.800 --> 00:17:35.560
means that to escape from that mass within

445
00:17:35.560 --> 00:17:37.480
that small area, you'd have to travel faster

446
00:17:37.480 --> 00:17:40.400
than the speed of light. So that's where you

447
00:17:40.400 --> 00:17:42.200
get the event horizon of a black hole. But

448
00:17:42.200 --> 00:17:44.400
the physical object inside the black hole, if

449
00:17:44.400 --> 00:17:45.920
there is one, and we don't know if there is

450
00:17:45.920 --> 00:17:47.880
one, is probably smaller than the size of

451
00:17:47.880 --> 00:17:50.560
that event horizon. Now, I

452
00:17:50.720 --> 00:17:52.800
am not an expert in this. My understanding

453
00:17:52.800 --> 00:17:54.680
from what I've seen written is that people

454
00:17:54.680 --> 00:17:57.410
think quark stars would be big

455
00:17:57.410 --> 00:18:00.090
enough that the gravity on their surface is

456
00:18:00.090 --> 00:18:02.050
low enough that light could escape, so they'd

457
00:18:02.050 --> 00:18:03.730
be bigger than the event horizon, so that

458
00:18:03.730 --> 00:18:06.210
we'd see them as physical objects. But it may

459
00:18:06.210 --> 00:18:08.330
be that the next step down is smaller than

460
00:18:08.330 --> 00:18:10.250
the event horizon. So you have a black hole.

461
00:18:10.730 --> 00:18:12.970
Fundamentally, what happens with the matter

462
00:18:12.970 --> 00:18:15.570
inside a black hole and, um, what empty space

463
00:18:15.570 --> 00:18:17.570
you have inside neutrons and stuff is pushing

464
00:18:17.570 --> 00:18:19.970
the boundaries of our knowledge of how matter

465
00:18:19.970 --> 00:18:22.700
works and how particle physics works. We do

466
00:18:22.700 --> 00:18:24.260
think there are these subatomic particles.

467
00:18:24.260 --> 00:18:25.540
There's a lot of evidence for that. And

468
00:18:25.540 --> 00:18:27.540
that's where the RDF quark stars come from.

469
00:18:28.020 --> 00:18:30.420
Knowledge of what quarks are made upon is

470
00:18:30.500 --> 00:18:32.060
really pushing the boundaries of what we

471
00:18:32.060 --> 00:18:34.780
know. And I'm, um, nowhere near qualified to

472
00:18:34.780 --> 00:18:36.980
comment on that, other than that there is

473
00:18:36.980 --> 00:18:39.700
speculation that you could possibly have even

474
00:18:39.700 --> 00:18:42.220
smaller components that behave

475
00:18:42.220 --> 00:18:44.620
differently. And this is where, as we get

476
00:18:44.620 --> 00:18:46.460
more energetic particle colliders in the

477
00:18:46.460 --> 00:18:49.130
future, as we get more better telescopes,

478
00:18:49.130 --> 00:18:51.690
better instrumentation all around, these are

479
00:18:51.690 --> 00:18:53.650
the kind of questions that people want to

480
00:18:53.650 --> 00:18:55.250
answer as we push that boundary of knowledge

481
00:18:55.250 --> 00:18:58.050
back. But it's really, at this point is

482
00:18:58.050 --> 00:19:00.170
SOC is asking questions that are at the

483
00:19:00.170 --> 00:19:02.090
boundaries of what our knowledge of modern

484
00:19:02.090 --> 00:19:04.970
physics is. And, uh, it's by asking these

485
00:19:04.970 --> 00:19:06.250
kind of questions that we'll learn the

486
00:19:06.250 --> 00:19:08.050
answers. But we're not there yet.

487
00:19:08.290 --> 00:19:11.290
Andrew Dunkley: No, no, we're not. But if, uh, we didn't ask

488
00:19:11.290 --> 00:19:13.730
questions like this, we'd never go looking

489
00:19:13.730 --> 00:19:16.390
for the answers, and we'd probably

490
00:19:16.390 --> 00:19:17.910
stagnate as a species.

491
00:19:18.150 --> 00:19:20.750
Jonti Horner: So, I mean, if you go back a long time, you

492
00:19:20.750 --> 00:19:22.110
know, if we didn't ask questions, we'd

493
00:19:22.110 --> 00:19:23.830
probably still be sitting around saying, me

494
00:19:23.830 --> 00:19:26.390
wish fire hot and not actually having the

495
00:19:26.390 --> 00:19:28.710
ability to have fires in. A day like today

496
00:19:28.710 --> 00:19:30.510
will be extremely miserable with the drizzly

497
00:19:30.510 --> 00:19:31.990
rain, because at least the fire that I've had

498
00:19:31.990 --> 00:19:33.030
on has kept me warm.

499
00:19:33.270 --> 00:19:36.190
Andrew Dunkley: Yeah, yeah, absolutely. Uh, thanks for

500
00:19:36.190 --> 00:19:38.430
the question. Istok. Lovely to hear from you.

501
00:19:38.430 --> 00:19:40.430
Hope all is well in Slovenia.

502
00:19:40.430 --> 00:19:42.790
This is Space Nuts with Andrew Duckley and

503
00:19:42.790 --> 00:19:43.750
Jonti Horner.

504
00:19:46.680 --> 00:19:48.760
Generic: Three, two, one.

505
00:19:49.400 --> 00:19:52.280
Andrew Dunkley: Space Nuts. Our next question

506
00:19:52.920 --> 00:19:55.680
is, uh, an audio question I do

507
00:19:55.680 --> 00:19:58.240
believe. Now, forgive me, I may have got your

508
00:19:58.240 --> 00:20:00.770
name wrong. I couldn't quite pick it up. Uh,

509
00:20:00.770 --> 00:20:02.840
maybe it was the accent, maybe it was just my

510
00:20:02.840 --> 00:20:05.760
lousy capacity to translate, but

511
00:20:05.760 --> 00:20:07.160
I think it's Foster.

512
00:20:07.560 --> 00:20:10.360
Speaker D: Hello, Andrew. Hello, Fred. And

513
00:20:10.360 --> 00:20:13.320
hello, Jonathan. I am from

514
00:20:13.320 --> 00:20:16.200
Norway, and I have a question for you.

515
00:20:16.310 --> 00:20:19.160
Uh, in relation to Interstellar, the

516
00:20:19.160 --> 00:20:21.760
movie, probably my favorite space

517
00:20:21.760 --> 00:20:24.520
movie of all time. And

518
00:20:24.680 --> 00:20:27.400
I have a question about the wormhole. And

519
00:20:27.560 --> 00:20:29.160
what kind of parameters

520
00:20:29.960 --> 00:20:32.920
theoretical. Has to be in order or to

521
00:20:32.920 --> 00:20:35.400
be in place for this to be possible and

522
00:20:35.640 --> 00:20:38.330
everything that we will discover or

523
00:20:38.330 --> 00:20:40.770
maybe, uh, youth, such a

524
00:20:40.930 --> 00:20:43.730
phenomena at some point. Thank you.

525
00:20:44.530 --> 00:20:47.250
Andrew Dunkley: Okay. Um, thank you, Foster. I think that's

526
00:20:47.250 --> 00:20:49.130
what your name was. Norway. I was there

527
00:20:49.130 --> 00:20:51.370
recently. Um, only in the last few months.

528
00:20:51.370 --> 00:20:53.650
And what a beautiful country you have.

529
00:20:54.370 --> 00:20:57.250
I got to stop in, I think, four or

530
00:20:57.250 --> 00:21:00.050
five different places, um, throughout

531
00:21:00.050 --> 00:21:02.810
Norway. And I learned a lot about the. The

532
00:21:02.810 --> 00:21:05.550
country, uh, uh, Jonti.

533
00:21:05.550 --> 00:21:07.590
Because, uh, they don't have much arable

534
00:21:07.590 --> 00:21:08.550
land. It's a.

535
00:21:08.550 --> 00:21:09.030
Jonti Horner: It's.

536
00:21:09.270 --> 00:21:11.510
Andrew Dunkley: They've got water and they've got mountains.

537
00:21:11.830 --> 00:21:14.390
There's not much flat ground. It's so un

538
00:21:14.390 --> 00:21:16.790
Australian. Very un

539
00:21:16.790 --> 00:21:19.150
Australian. Um, and because they've got so

540
00:21:19.150 --> 00:21:21.550
much water, uh, they can generate a lot of

541
00:21:21.550 --> 00:21:23.870
electricity. And nobody pays for electricity

542
00:21:23.870 --> 00:21:26.850
in Norway, from what I was told. Um,

543
00:21:26.850 --> 00:21:29.630
but they don't really have much

544
00:21:29.630 --> 00:21:32.410
room to grow crops. And, uh, and it's too

545
00:21:32.410 --> 00:21:35.170
cold most of the time anyway. Uh, that said,

546
00:21:35.250 --> 00:21:37.210
when we went to North Cape, which is the

547
00:21:37.210 --> 00:21:39.010
northernmost tip of Europe, which is

548
00:21:39.330 --> 00:21:41.810
obviously in Norway, as in north,

549
00:21:42.450 --> 00:21:44.850
um, 28 degrees. It was

550
00:21:45.170 --> 00:21:47.850
28 degrees. And the locals were freaking out.

551
00:21:47.850 --> 00:21:50.570
That was a heat wave. Uh, to us it was just

552
00:21:50.570 --> 00:21:53.450
beautiful. But, um, one

553
00:21:53.450 --> 00:21:55.090
thing I did notice, and you'd probably be

554
00:21:55.090 --> 00:21:57.490
aware of this being, uh, from the Northern

555
00:21:57.490 --> 00:21:59.900
hemisphere, their summer,

556
00:22:00.700 --> 00:22:03.580
where most of the population lives, their

557
00:22:03.580 --> 00:22:06.060
summer is not like a summer here

558
00:22:06.780 --> 00:22:09.100
because they are further north than we are

559
00:22:09.100 --> 00:22:11.260
south, if that makes sense.

560
00:22:11.980 --> 00:22:14.680
So our summers can be much more severe. Uh,

561
00:22:15.110 --> 00:22:16.620
um, but

562
00:22:18.780 --> 00:22:20.620
their summers are very mild,

563
00:22:22.140 --> 00:22:23.620
especially when you get to places like

564
00:22:23.620 --> 00:22:26.320
Greenland and Iceland and, uh,

565
00:22:27.500 --> 00:22:30.220
even in Canada, places like that. It's a

566
00:22:30.220 --> 00:22:30.700
different world.

567
00:22:31.420 --> 00:22:33.620
Jonti Horner: Yeah, I mean, I know for a fact, having grown

568
00:22:33.620 --> 00:22:35.460
up in the uk, and I, uh, suspect that heat

569
00:22:35.460 --> 00:22:38.300
wave in Norway was brutal that he hits

570
00:22:38.300 --> 00:22:39.780
different in those countries because the

571
00:22:39.780 --> 00:22:41.499
buildings are engineered to keep you warm,

572
00:22:41.499 --> 00:22:42.460
not to keep you cool.

573
00:22:42.460 --> 00:22:43.020
Andrew Dunkley: Correct.

574
00:22:43.020 --> 00:22:45.220
Jonti Horner: And so, yeah, I'm complaining about the

575
00:22:45.220 --> 00:22:47.100
horrible night I had the other night with the

576
00:22:47.100 --> 00:22:49.260
power outage and the heat wave that we had.

577
00:22:49.900 --> 00:22:52.380
But it was made more bearable by the fact

578
00:22:52.380 --> 00:22:54.460
that the design of this house is more around

579
00:22:55.190 --> 00:22:56.750
keeping people cool in summer and keeping

580
00:22:56.750 --> 00:22:59.390
them warm in winter. Whereas when I was doing

581
00:22:59.390 --> 00:23:02.270
my PhD in Oxford back in 2003, we

582
00:23:02.270 --> 00:23:03.790
had what was then the hottest summer on

583
00:23:03.790 --> 00:23:06.230
record in the UK and now is a footnote in

584
00:23:06.230 --> 00:23:07.710
history because things are much warmer now

585
00:23:07.710 --> 00:23:09.910
than they were. But we had a couple of days

586
00:23:09.910 --> 00:23:12.150
that were in the mid-30s. And I'm in this old

587
00:23:12.150 --> 00:23:14.390
building that is a couple of hundred years

588
00:23:14.390 --> 00:23:17.230
old with south facing windows to get the

589
00:23:17.230 --> 00:23:19.030
light, northern hemisphere, the sun's in the

590
00:23:19.030 --> 00:23:21.640
south, um, on the ground floor. So you could

591
00:23:21.640 --> 00:23:23.560
only open these floor to ceiling windows by

592
00:23:23.560 --> 00:23:25.480
about an inch because they're security locked

593
00:23:25.480 --> 00:23:28.240
down. And uh, no air conditioning. A lot of

594
00:23:28.240 --> 00:23:30.960
computers in there. It was absolutely awful.

595
00:23:31.520 --> 00:23:33.440
Um, the other thing that I really notice is

596
00:23:34.000 --> 00:23:37.000
I'm into one where I'm 27 degrees south. The

597
00:23:37.000 --> 00:23:39.800
day length barely varies. When I grew up, you

598
00:23:39.800 --> 00:23:41.200
know, in the winter I'd go to school in the

599
00:23:41.200 --> 00:23:44.160
dark and come home in the dark. And here the

600
00:23:44.160 --> 00:23:46.320
day length barely varies. But we're already

601
00:23:46.320 --> 00:23:48.400
well off topic from, um, the awesome

602
00:23:48.400 --> 00:23:48.720
question.

603
00:23:49.610 --> 00:23:52.570
I should say that my movie viewing

604
00:23:52.810 --> 00:23:55.330
over the last decade or 10 or 15 years has

605
00:23:55.330 --> 00:23:57.210
been much more limited thanks to how busy

606
00:23:57.210 --> 00:23:59.490
I've been in my career. And Interstellar has

607
00:23:59.490 --> 00:24:02.290
been on my to watch list for years and never

608
00:24:02.290 --> 00:24:04.410
quite happened. No, we've got Brilliant,

609
00:24:04.570 --> 00:24:07.130
Gotta do it. And um, it's on the list and I

610
00:24:07.130 --> 00:24:08.690
wish I'd seen it at the cinemas, but it's

611
00:24:08.690 --> 00:24:11.450
always been a not today thing. It's never

612
00:24:11.450 --> 00:24:12.210
quite happened.

613
00:24:12.210 --> 00:24:15.130
Andrew Dunkley: You know, I've watched it four or five times.

614
00:24:15.710 --> 00:24:18.630
Yeah, I love it. And I think

615
00:24:18.630 --> 00:24:20.870
what makes it for me being someone in radio

616
00:24:20.870 --> 00:24:23.750
is the musical score that goes with

617
00:24:23.750 --> 00:24:25.870
it. It is phenomenal.

618
00:24:27.310 --> 00:24:29.110
Jonti Horner: It's meant to be amazing and I'm just sad

619
00:24:29.110 --> 00:24:30.870
I've not got around to seeing it yet. But one

620
00:24:30.870 --> 00:24:33.190
of the things I know about it is that it is

621
00:24:33.190 --> 00:24:35.230
pretty hardcore on the science. But they did

622
00:24:35.230 --> 00:24:36.710
a really good job of getting some of the

623
00:24:36.710 --> 00:24:39.710
world's really leading theoretical physicists

624
00:24:40.190 --> 00:24:42.430
to give input and get really good scientific

625
00:24:42.510 --> 00:24:45.510
advice. And it does to my understanding.

626
00:24:45.510 --> 00:24:47.110
And I say this with a bit of a caveat that

627
00:24:47.110 --> 00:24:48.390
I've not seen it. But my understanding,

628
00:24:48.390 --> 00:24:51.110
talking to colleagues is it does really well.

629
00:24:51.110 --> 00:24:53.310
What I like in good science fiction is where

630
00:24:53.550 --> 00:24:55.990
it gets the science right, except where it

631
00:24:55.990 --> 00:24:57.390
needs to get the science wrong to make the

632
00:24:57.390 --> 00:24:59.470
plot advance. Um, exactly. And I'm always

633
00:24:59.470 --> 00:25:01.430
really happy with that. I get really grumpy

634
00:25:01.430 --> 00:25:03.150
with films that get the science wrong to no

635
00:25:03.150 --> 00:25:06.110
good reason. I watch films and they've

636
00:25:06.110 --> 00:25:08.630
got a night sky, and it's not the Earth night

637
00:25:08.630 --> 00:25:11.520
sky. And it's like you're on Earth. It is

638
00:25:11.520 --> 00:25:13.440
really cheap to point a camera at the sky and

639
00:25:13.440 --> 00:25:15.880
get a picture. Why would you make up a false

640
00:25:15.880 --> 00:25:18.200
night sky? There's no need for that. But if

641
00:25:18.200 --> 00:25:20.640
you do everything you can to get the science

642
00:25:20.640 --> 00:25:23.400
right, or the science to fit our best current

643
00:25:23.400 --> 00:25:25.360
understanding in the case of things we've

644
00:25:25.360 --> 00:25:28.320
never directly experienced or seen, but you

645
00:25:28.400 --> 00:25:30.280
circumvent that to make the plot work, I'm

646
00:25:30.280 --> 00:25:32.240
totally cool with that. That's a very knowing

647
00:25:32.240 --> 00:25:33.120
use of science.

648
00:25:34.160 --> 00:25:36.720
This is all about wormholes, which are a

649
00:25:36.720 --> 00:25:39.500
staple of science fiction because

650
00:25:39.500 --> 00:25:41.740
they are a hypothetical way that we could

651
00:25:41.740 --> 00:25:43.260
move from one place in the universe to

652
00:25:43.260 --> 00:25:45.620
another at speeds much greater than the speed

653
00:25:45.620 --> 00:25:47.180
of light, by essentially cutting out the

654
00:25:47.180 --> 00:25:50.020
middleman. And the way it's always envisaged

655
00:25:50.100 --> 00:25:52.580
is to envisage the universe drawn on a two

656
00:25:52.580 --> 00:25:54.980
dimensional sheet of paper and then folding

657
00:25:54.980 --> 00:25:56.860
the sheet of paper so that two places that

658
00:25:56.860 --> 00:25:59.020
are nowhere near each other touch and saying,

659
00:25:59.020 --> 00:26:00.580
what if you could tunnel between them?

660
00:26:01.700 --> 00:26:04.100
Wormholes have their origins in

661
00:26:04.580 --> 00:26:06.580
particular solutions to the equations from

662
00:26:06.580 --> 00:26:09.460
Einstein's general relativity. And they are

663
00:26:09.460 --> 00:26:11.780
purely theoretical constructs at the minute.

664
00:26:11.780 --> 00:26:13.780
They're possible solutions to the model that

665
00:26:13.780 --> 00:26:16.740
Einstein developed that offer the

666
00:26:16.740 --> 00:26:19.380
possibility that you could have

667
00:26:19.380 --> 00:26:21.340
instantaneous travel between two distant

668
00:26:21.340 --> 00:26:23.860
points. There's a lot of debate over whether

669
00:26:23.860 --> 00:26:26.500
they are anything more than a theoretical

670
00:26:26.500 --> 00:26:28.860
construct. And of course, this is all

671
00:26:29.260 --> 00:26:31.100
predicated on, um, the idea that

672
00:26:31.580 --> 00:26:34.580
Einstein's model of the universe is

673
00:26:34.580 --> 00:26:36.540
a correct analysis of what's actually there.

674
00:26:37.100 --> 00:26:39.020
And it may well be that in 50 years or 100

675
00:26:39.020 --> 00:26:40.620
years, when we've got incredibly more

676
00:26:40.620 --> 00:26:42.940
powerful observing tools than we have now, we

677
00:26:42.940 --> 00:26:45.060
start to see the cracks in Einstein's model

678
00:26:45.060 --> 00:26:46.980
just the same way that we did with Newton's

679
00:26:46.980 --> 00:26:49.420
gravitation a couple of hundred years ago.

680
00:26:50.300 --> 00:26:52.940
There are a few variants of wormholes that

681
00:26:52.940 --> 00:26:54.460
have been proposed based on different

682
00:26:54.700 --> 00:26:56.140
solutions to those

683
00:26:57.100 --> 00:26:59.180
theories. Some of them have even come about

684
00:26:59.180 --> 00:27:01.820
kind of tied to. You could potentially have a

685
00:27:01.820 --> 00:27:04.660
rotating black hole that would turn into,

686
00:27:04.980 --> 00:27:06.660
that would allow you to travel through the

687
00:27:06.660 --> 00:27:08.860
black hole without getting destroyed and use

688
00:27:08.860 --> 00:27:11.860
it as a tunnel to somewhere else. There

689
00:27:11.860 --> 00:27:14.660
are also solutions to those equations

690
00:27:15.220 --> 00:27:17.100
which could let you set up one of these

691
00:27:17.100 --> 00:27:19.460
wormholes. One of the variants of this is

692
00:27:19.460 --> 00:27:21.300
known as an Einstein Rosen bridge, I believe,

693
00:27:21.970 --> 00:27:24.540
um, that could set up a permanent tunnel that

694
00:27:24.540 --> 00:27:26.860
could be traversable. But in order to make

695
00:27:26.860 --> 00:27:29.060
that work, you need material which has

696
00:27:29.060 --> 00:27:31.420
negative energy, which often gets talked

697
00:27:31.420 --> 00:27:34.100
about as exotic matter. And I've been

698
00:27:34.100 --> 00:27:36.420
listening to an audiobook series that's very

699
00:27:36.420 --> 00:27:38.060
good, fun, but very pulpy, called

700
00:27:38.060 --> 00:27:40.140
Expeditionary Force. And they use wormholes

701
00:27:40.140 --> 00:27:41.420
all the time. And they're always talking

702
00:27:41.420 --> 00:27:43.740
about things made of exotic matter by

703
00:27:43.980 --> 00:27:46.140
technologically advanced species millions of

704
00:27:46.140 --> 00:27:48.460
years more advanced than we are. It's become

705
00:27:48.460 --> 00:27:51.420
a staple of science fiction as uh, to

706
00:27:51.420 --> 00:27:54.340
whether we will ever find them or ever

707
00:27:54.340 --> 00:27:56.620
be able to use them. We simply don't know yet

708
00:27:56.620 --> 00:27:57.820
at uh, the minute. They're a purely

709
00:27:57.820 --> 00:27:59.620
theoretical constructs. So they're kind of an

710
00:27:59.620 --> 00:28:02.450
extreme prediction of one model of how we

711
00:28:02.450 --> 00:28:05.130
think the universe could work. They are

712
00:28:05.130 --> 00:28:07.770
possibly something that with sufficiently

713
00:28:07.770 --> 00:28:10.010
advanced far future technology, you could

714
00:28:10.010 --> 00:28:12.650
envision the ability to make them and control

715
00:28:12.730 --> 00:28:15.370
them. But that would require us to have

716
00:28:15.930 --> 00:28:17.810
technological advances beyond what we can

717
00:28:17.810 --> 00:28:19.690
imagine here and probably physics to work

718
00:28:19.690 --> 00:28:21.450
differently to how we currently understand

719
00:28:21.530 --> 00:28:24.370
that it would do. I'm loath to say we

720
00:28:24.370 --> 00:28:26.170
couldn't do it because that strikes me as a

721
00:28:26.170 --> 00:28:28.540
bit like the people who in 1910s said we will

722
00:28:28.540 --> 00:28:30.660
never have heavier than air flight just

723
00:28:30.660 --> 00:28:33.580
before the Wright brothers flew. Um,

724
00:28:33.620 --> 00:28:36.340
because we don't know everything. We, we're

725
00:28:36.340 --> 00:28:37.980
in this little bubble of knowledge in an

726
00:28:37.980 --> 00:28:40.900
ocean of things, um, that we don't

727
00:28:40.900 --> 00:28:43.890
know yet in an ocean of darkness. And um,

728
00:28:43.939 --> 00:28:46.820
these things like wormholes are uh, natural

729
00:28:46.820 --> 00:28:48.860
products of our efforts to push that boundary

730
00:28:48.860 --> 00:28:51.820
of knowledge further. All of this is a

731
00:28:51.820 --> 00:28:54.640
very long winded, say, way of saying I don't

732
00:28:54.640 --> 00:28:56.520
have the real knowledge of how all this

733
00:28:56.520 --> 00:28:59.120
works. I'm not that kind of theoretical

734
00:28:59.120 --> 00:29:01.680
physicist. It's all very much

735
00:29:01.760 --> 00:29:04.680
beyond me. I greatly admire the kind

736
00:29:04.680 --> 00:29:06.080
of scientists that have come up with these

737
00:29:06.080 --> 00:29:08.040
ideas. I think they are fabulous, fabulous

738
00:29:08.040 --> 00:29:10.720
ideas. And if the model is

739
00:29:10.720 --> 00:29:13.040
correct, then wormholes could exist.

740
00:29:13.520 --> 00:29:15.640
You then have the leap of could they be

741
00:29:15.640 --> 00:29:17.640
stable for long enough for us to ever observe

742
00:29:17.640 --> 00:29:19.720
them? And of course the most important thing

743
00:29:19.720 --> 00:29:21.280
about a theory is it makes testable

744
00:29:21.280 --> 00:29:23.040
predictions. And so I'd love to see

745
00:29:23.680 --> 00:29:25.320
observations in the future confirm that

746
00:29:25.320 --> 00:29:28.120
wormholes can exist. To then have a leap

747
00:29:28.120 --> 00:29:30.400
beyond that to could we ever develop them and

748
00:29:30.400 --> 00:29:33.400
use them? I'd love to think we will do. But

749
00:29:33.400 --> 00:29:35.680
I think unlike the search for life elsewhere,

750
00:29:35.680 --> 00:29:36.960
where I think there's a chance we'll know the

751
00:29:36.960 --> 00:29:39.680
answer in a lifetime, I think with this it's

752
00:29:39.680 --> 00:29:41.560
very unlikely we'd know the answer within our

753
00:29:41.560 --> 00:29:44.520
lifetime. Unless the answer is no. And the

754
00:29:44.520 --> 00:29:46.760
answer is no would come about Us getting a

755
00:29:46.760 --> 00:29:48.840
newer model for how all these things work to

756
00:29:48.840 --> 00:29:51.200
explain new observations that no longer

757
00:29:51.200 --> 00:29:53.880
offers this as a possibility. Um, I don't

758
00:29:53.880 --> 00:29:55.560
think that's going to happen in all honesty.

759
00:29:56.200 --> 00:29:59.160
But yeah, it's an awesome question.

760
00:29:59.160 --> 00:30:00.640
I wish it was something I could be more

761
00:30:00.640 --> 00:30:02.960
knowledgeable about. But, um, if you went

762
00:30:02.960 --> 00:30:05.080
back 400 years, it was possible for one

763
00:30:05.080 --> 00:30:07.680
person to have the entirety of the world's

764
00:30:07.680 --> 00:30:08.800
knowledge. And that's why you've got these

765
00:30:08.800 --> 00:30:11.480
incredible polymaths who could be chemists

766
00:30:11.480 --> 00:30:13.680
and engineers and biologists and physicists

767
00:30:13.680 --> 00:30:15.320
and astronomers all at the same time.

768
00:30:16.090 --> 00:30:18.050
Nowadays the breadth of human knowledge is so

769
00:30:18.050 --> 00:30:21.050
incredibly vast that nobody

770
00:30:21.050 --> 00:30:22.530
can be an expert in all of it. In fact,

771
00:30:22.530 --> 00:30:24.090
you're normally an expert in a very narrow

772
00:30:24.090 --> 00:30:26.810
area. And it's very fair to say that

773
00:30:26.890 --> 00:30:29.690
wormholes and um, the

774
00:30:29.690 --> 00:30:32.170
complexities of higher dimensional space time

775
00:30:32.170 --> 00:30:34.090
and theoretical physics in that sense, and

776
00:30:34.250 --> 00:30:36.210
you know, the extreme extrapolations of

777
00:30:36.210 --> 00:30:38.850
general relativity are uh, way outside my

778
00:30:38.850 --> 00:30:40.530
wheelhouse. I'm not really qualified to say

779
00:30:40.530 --> 00:30:42.170
much more than that, even having done a bit

780
00:30:42.170 --> 00:30:43.120
of reading around it.

781
00:30:43.670 --> 00:30:45.910
Andrew Dunkley: I like to think that

782
00:30:47.030 --> 00:30:49.350
fundamentally all things are possible. But

783
00:30:49.360 --> 00:30:52.190
uh, I know, um, traveling faster than

784
00:30:52.190 --> 00:30:54.030
light speed isn't because of the amount of

785
00:30:54.030 --> 00:30:57.030
energy it requires, but maybe folding space

786
00:30:57.030 --> 00:30:59.830
or developing wormhole technology could

787
00:30:59.830 --> 00:31:01.910
be the workaround.

788
00:31:02.710 --> 00:31:05.630
So um, yeah, let's put a pin in

789
00:31:05.630 --> 00:31:07.470
that one for future reference when they've

790
00:31:07.470 --> 00:31:09.350
got it all figured out. But um, yeah,

791
00:31:09.750 --> 00:31:12.160
wormhole technology comes up in

792
00:31:12.160 --> 00:31:14.800
interstellar, uh, as created by a fourth

793
00:31:14.800 --> 00:31:17.800
dimension race. Um, I won't say any

794
00:31:17.800 --> 00:31:20.080
more than that, but uh, Foster, thanks for

795
00:31:20.080 --> 00:31:22.160
the question. Uh, I loved it, it was

796
00:31:22.160 --> 00:31:24.400
terrific. And yes, I agree with you. Probably

797
00:31:24.400 --> 00:31:26.160
my favorite,

798
00:31:27.199 --> 00:31:30.040
if at the very least in my top

799
00:31:30.040 --> 00:31:32.770
three, um, um,

800
00:31:32.770 --> 00:31:35.120
science fiction films, uh, although it's

801
00:31:35.120 --> 00:31:37.160
pretty close to not science fiction in many,

802
00:31:37.160 --> 00:31:39.600
many ways. Good on you, Foster. Thanks for

803
00:31:39.600 --> 00:31:40.080
the question.

804
00:31:42.740 --> 00:31:44.700
Jonti Horner: Okay, we checked all four systems and.

805
00:31:44.700 --> 00:31:46.940
Andrew Dunkley: Being with a go space nets now, final

806
00:31:46.940 --> 00:31:49.060
question today comes from Rob.

807
00:31:49.700 --> 00:31:52.100
As I understand the only way

808
00:31:52.340 --> 00:31:54.700
out of a singularity is by Hawking

809
00:31:54.700 --> 00:31:57.620
radiation. However, isn't the Big Bang

810
00:31:58.340 --> 00:32:01.260
another example? If so, then at a

811
00:32:01.260 --> 00:32:04.260
critical universal size an explosion

812
00:32:04.260 --> 00:32:07.140
is imminent. Uh, this suggests that

813
00:32:07.140 --> 00:32:09.140
there were a number of singularities before

814
00:32:09.140 --> 00:32:11.300
the Big Bang that combined to reach

815
00:32:11.870 --> 00:32:14.350
critical Big Bang mass. What do you think?

816
00:32:14.920 --> 00:32:17.230
Uh, could the very early black holes suggest

817
00:32:17.310 --> 00:32:19.110
that a, ah, number were floating around

818
00:32:19.110 --> 00:32:21.870
before the Big Bang and attracted mass

819
00:32:22.030 --> 00:32:24.750
from the Big Bang to form the galaxies?

820
00:32:25.230 --> 00:32:25.670
Jonti Horner: Wow.

821
00:32:25.670 --> 00:32:27.550
Andrew Dunkley: Rob put a lot of thought into that one.

822
00:32:28.990 --> 00:32:31.110
Jonti Horner: Absolutely. And this is yet another one that

823
00:32:31.110 --> 00:32:33.630
gets to pushing the boundaries of any of our

824
00:32:33.630 --> 00:32:36.030
knowledge, to be honest. And this

825
00:32:36.350 --> 00:32:39.340
question from Rob is a really

826
00:32:39.340 --> 00:32:41.860
good illustration of where the boundaries of

827
00:32:41.860 --> 00:32:43.860
analogy when it comes to cosmology and

828
00:32:43.860 --> 00:32:45.980
cosmogenesis, the origin of the universe,

829
00:32:46.620 --> 00:32:48.860
are, ah, where science and philosophy meet,

830
00:32:49.500 --> 00:32:51.660
where you start getting to the point where

831
00:32:52.620 --> 00:32:54.940
you are going so far beyond what we can

832
00:32:54.940 --> 00:32:57.180
observe and what is possible

833
00:32:57.820 --> 00:32:59.340
to understand with our current laws of

834
00:32:59.340 --> 00:33:01.300
physics. That discussion of it moves away

835
00:33:01.300 --> 00:33:03.040
from science and into the realms of physics,

836
00:33:03.190 --> 00:33:05.670
philosophy and thinking about how we think.

837
00:33:06.070 --> 00:33:08.910
And uh, the reason I say that is that our

838
00:33:08.910 --> 00:33:11.350
current best understanding, as I remember it

839
00:33:11.350 --> 00:33:14.150
from the things I've learned, is that,

840
00:33:15.020 --> 00:33:17.830
uh, space and time are inherently properties

841
00:33:17.830 --> 00:33:20.750
of the universe. Which means

842
00:33:20.750 --> 00:33:23.630
that the question of what is before

843
00:33:23.630 --> 00:33:25.510
the Big Bang or the question of what's

844
00:33:25.510 --> 00:33:28.270
outside the universe are things that are

845
00:33:28.270 --> 00:33:30.470
questions of philosophy rather than science.

846
00:33:31.530 --> 00:33:33.730
Because by definition you can't have a before

847
00:33:33.730 --> 00:33:35.970
the Big Bang when time only started at the

848
00:33:35.970 --> 00:33:37.450
Big Bang and time is a property of the

849
00:33:37.450 --> 00:33:39.810
universe. Similarly, you can't have a concept

850
00:33:39.810 --> 00:33:42.530
of outside the universe when space is of the

851
00:33:42.530 --> 00:33:44.970
universe. Yeah, now as I say this, to me

852
00:33:44.970 --> 00:33:47.210
really gets to be philosophy rather than

853
00:33:47.210 --> 00:33:49.570
science because that makes my head hurt. And

854
00:33:49.570 --> 00:33:51.250
I think anything that makes my head hurt can

855
00:33:51.250 --> 00:33:53.280
be described as philosophy. Um,

856
00:33:54.090 --> 00:33:56.290
but it is a lot of it's about how we think

857
00:33:56.290 --> 00:33:59.200
and how we visualize stuff. So I suspect

858
00:33:59.200 --> 00:34:01.080
if we got somebody on who was one of the

859
00:34:01.080 --> 00:34:02.840
world's leading cosmologists, they could

860
00:34:02.840 --> 00:34:04.280
answer this a lot more clearly. But they'd

861
00:34:04.280 --> 00:34:06.920
probably be saying that we can't really say

862
00:34:06.920 --> 00:34:08.840
anything about what was happening before the

863
00:34:08.840 --> 00:34:11.640
Big Bang because before the Big Bang is a

864
00:34:11.640 --> 00:34:13.640
meaningless concept. Before the Big Bang,

865
00:34:13.640 --> 00:34:14.640
time didn't exist.

866
00:34:15.040 --> 00:34:17.440
Andrew Dunkley: Well, the question has been asked

867
00:34:17.520 --> 00:34:19.920
directly to us in the past, what was there

868
00:34:19.920 --> 00:34:22.640
before the Big Bang? And Fred's answer is

869
00:34:22.640 --> 00:34:25.640
always nothing. Well,

870
00:34:25.640 --> 00:34:27.880
no, no, no, he doesn't say nothing. He says

871
00:34:27.880 --> 00:34:28.760
we don't know.

872
00:34:29.000 --> 00:34:31.480
Jonti Horner: It is really a we don't know. Now

873
00:34:31.880 --> 00:34:34.000
there are a number of theories out there

874
00:34:34.000 --> 00:34:36.479
because this verges on philosophy and um,

875
00:34:37.160 --> 00:34:39.640
religion. Not in the, not in the sense of any

876
00:34:39.640 --> 00:34:41.800
given named faith, but rather

877
00:34:42.840 --> 00:34:45.320
the point at uh, which you move from

878
00:34:45.880 --> 00:34:48.280
evidence and theory and prediction

879
00:34:48.680 --> 00:34:51.530
to faith. Um, and

880
00:34:52.010 --> 00:34:54.090
I'm not myself religious, but I've got a lot

881
00:34:54.090 --> 00:34:56.170
of colleagues that are. And there is, despite

882
00:34:56.650 --> 00:34:58.450
what some people try and manufacture, there

883
00:34:58.450 --> 00:35:00.530
is no conflict between religion and science

884
00:35:00.530 --> 00:35:03.410
at all. Um, Terry Pratchett, who I

885
00:35:03.410 --> 00:35:04.970
obviously put a lot of salt by because I

886
00:35:04.970 --> 00:35:06.450
mentioned him very, very often, had some

887
00:35:06.450 --> 00:35:07.850
really good discussions of this in the

888
00:35:07.850 --> 00:35:10.610
discworld books and the concept

889
00:35:10.610 --> 00:35:12.050
that. I think it's in the science of

890
00:35:12.050 --> 00:35:14.810
Discworld books that science and religion are

891
00:35:14.810 --> 00:35:17.430
orthogonal and that science. Science operates

892
00:35:17.430 --> 00:35:19.630
in the absence of belief because it's about

893
00:35:19.630 --> 00:35:22.630
evidence, whereas belief operate. Religion

894
00:35:22.630 --> 00:35:25.630
operates in the domain of outside of evidence

895
00:35:25.630 --> 00:35:27.870
because it's about belief. And,

896
00:35:28.910 --> 00:35:30.830
you know, I don't need to believe. This table

897
00:35:30.830 --> 00:35:32.630
in front of me is there because I put the

898
00:35:32.630 --> 00:35:34.070
evidence of my hand resting on it in my

899
00:35:34.070 --> 00:35:36.390
microphone set. There's a lot of really

900
00:35:36.390 --> 00:35:37.990
interesting stuff there. And, uh, the reason

901
00:35:37.990 --> 00:35:39.790
that I've gone on that little bit of a detour

902
00:35:39.870 --> 00:35:42.270
is that questions about what happened before

903
00:35:42.270 --> 00:35:45.120
the Big Bang are questions that, uh, are

904
00:35:45.120 --> 00:35:47.520
beyond what we can. What of. Beyond what we

905
00:35:47.520 --> 00:35:49.360
can know. Because all of our ability to

906
00:35:49.360 --> 00:35:52.360
observe and measure is limited to

907
00:35:52.680 --> 00:35:55.240
the results of the Big Bang in terms

908
00:35:55.400 --> 00:35:57.080
of space and time.

909
00:35:58.280 --> 00:36:00.640
Those started at the Big Bang. So to try and

910
00:36:00.640 --> 00:36:02.480
understand anything about before the Big Bang

911
00:36:02.480 --> 00:36:04.320
with those in our current understanding of

912
00:36:04.320 --> 00:36:07.280
how it works becomes a matter of religion or

913
00:36:07.280 --> 00:36:08.920
faith, because there is no way of having

914
00:36:08.920 --> 00:36:11.880
evidence either way. Um, apologies for a

915
00:36:11.880 --> 00:36:13.200
bit of a background noise, by the way. The

916
00:36:13.200 --> 00:36:15.000
rain is pounding on the wonderful roof here,

917
00:36:15.000 --> 00:36:16.600
which is a very Australian experience.

918
00:36:16.800 --> 00:36:18.720
Andrew Dunkley: Uh, now I'm a thousand kilometers away from

919
00:36:18.720 --> 00:36:20.320
you, but it just started raining here as

920
00:36:20.320 --> 00:36:20.600
well.

921
00:36:21.640 --> 00:36:24.120
Jonti Horner: Spooky action at a distance is what that is.

922
00:36:24.120 --> 00:36:26.360
Andrew Dunkley: Yeah, it was probably a wormhole.

923
00:36:26.680 --> 00:36:28.760
Jonti Horner: Yeah, absolutely. It's teleporting through,

924
00:36:28.760 --> 00:36:30.600
which is why it's been so dry here recently.

925
00:36:30.600 --> 00:36:32.400
You're getting all the fun. Yeah.

926
00:36:32.400 --> 00:36:35.360
So with this question from Rob, the challenge

927
00:36:35.360 --> 00:36:36.960
is that you're asking the questions that

928
00:36:36.960 --> 00:36:38.360
we're all asking, trying to understand,

929
00:36:39.900 --> 00:36:41.420
but they're not questions we can really

930
00:36:41.420 --> 00:36:43.780
answer when it comes to things outside of the

931
00:36:43.780 --> 00:36:46.180
current universe. What that's led to is a

932
00:36:46.180 --> 00:36:48.700
number of different proposals of theoretical

933
00:36:48.780 --> 00:36:51.220
before the Big Bangs. One is that the Big

934
00:36:51.220 --> 00:36:53.260
Bang is the first thing that there ever was

935
00:36:53.260 --> 00:36:55.380
and will expand for forever, and that's it.

936
00:36:55.380 --> 00:36:57.340
And it's doom. One is that

937
00:36:58.300 --> 00:37:00.180
you have these Big Bangs followed by Big

938
00:37:00.180 --> 00:37:02.300
Crunches, and you get the cyclical nature of

939
00:37:02.300 --> 00:37:04.900
the universe with a reset. Um, a lot of our

940
00:37:04.900 --> 00:37:06.540
current theories suggest that the expansion

941
00:37:06.540 --> 00:37:08.140
of the universe is speeding up rather than

942
00:37:08.140 --> 00:37:10.200
slowing down, which argues against that.

943
00:37:10.760 --> 00:37:13.640
But we know in the past,

944
00:37:13.640 --> 00:37:15.440
and this is where it gets more to philosophy

945
00:37:15.440 --> 00:37:18.200
and religion and faith and complexity as

946
00:37:18.200 --> 00:37:20.560
well, is that, uh, in the early days of the

947
00:37:20.560 --> 00:37:23.240
universe, the different forces were unified

948
00:37:23.240 --> 00:37:25.360
and you get phase changes in the universe as

949
00:37:25.360 --> 00:37:27.560
the expansion happens in the universe cools.

950
00:37:28.150 --> 00:37:30.040
Um, and that's all in the very early time.

951
00:37:30.680 --> 00:37:33.520
But it's possible. And I've never found

952
00:37:33.520 --> 00:37:35.080
anyone who can explain to me that this

953
00:37:35.080 --> 00:37:36.400
wouldn't be possible. But it might be

954
00:37:36.400 --> 00:37:38.360
entirely wrong. This is jaunty speculation.

955
00:37:39.060 --> 00:37:40.740
Who's to say that there isn't another phase

956
00:37:40.740 --> 00:37:42.940
change at some point where something that we

957
00:37:42.940 --> 00:37:44.820
can only see as one force freezes out into

958
00:37:44.820 --> 00:37:47.740
two separate forces? Now we see examples of

959
00:37:47.740 --> 00:37:50.100
this all over the place. It's a total hop.

960
00:37:50.180 --> 00:37:53.100
But when I was doing my second postdoc, I was

961
00:37:53.100 --> 00:37:55.910
at the Open University in the UK and at

962
00:37:55.910 --> 00:37:57.780
uh, one of the conferences I went to, I met a

963
00:37:57.780 --> 00:37:59.500
young woman who was doing a chemistry based

964
00:37:59.500 --> 00:38:01.260
degree looking at chemistry on the moon

965
00:38:01.260 --> 00:38:04.100
Titan. And she was interested in

966
00:38:04.100 --> 00:38:05.900
the availability of different chemical

967
00:38:05.900 --> 00:38:08.570
reactions as to whether a place like Titan,

968
00:38:08.570 --> 00:38:11.290
180 degrees below freezing, could have the

969
00:38:11.290 --> 00:38:13.010
potential for life, given that there's liquid

970
00:38:13.010 --> 00:38:14.330
there in the form of liquid ethane and

971
00:38:14.330 --> 00:38:17.170
methane. And the standard accepted wisdom is

972
00:38:17.330 --> 00:38:19.050
no there isn't, because the more you cool

973
00:38:19.050 --> 00:38:20.650
down, the fewer chemical reactions are

974
00:38:20.650 --> 00:38:23.450
available. Just doesn't happen. But she

975
00:38:23.450 --> 00:38:26.090
looked at benzene, which is a chemical, a,

976
00:38:26.090 --> 00:38:27.890
ah, compound that at uh, room temperature

977
00:38:28.210 --> 00:38:29.970
there's a single version of benzene. You have

978
00:38:29.970 --> 00:38:32.890
the benzene ring. What she found was

979
00:38:32.890 --> 00:38:34.450
that if you cool benzene down to the

980
00:38:34.450 --> 00:38:37.210
conditions you get on Titan, benzene forms

981
00:38:37.210 --> 00:38:40.130
three different isomers. They're all benzene,

982
00:38:40.210 --> 00:38:42.330
but they're different shapes of those six

983
00:38:42.330 --> 00:38:44.450
carbon atoms in a ring. At, uh, room

984
00:38:44.450 --> 00:38:46.370
temperature, it's got enough energy that it

985
00:38:46.370 --> 00:38:48.330
vibrates around and they all blur out and you

986
00:38:48.330 --> 00:38:49.810
just get a single version. But you cool it

987
00:38:49.810 --> 00:38:51.490
down and you freeze it out to three distinct

988
00:38:51.490 --> 00:38:54.010
versions of benzene with slightly different

989
00:38:54.010 --> 00:38:56.490
chemistry. So suddenly by cooling it down and

990
00:38:56.490 --> 00:38:57.930
freezing it out, you get three times the

991
00:38:57.930 --> 00:38:59.810
availability of different chemical reactions

992
00:38:59.810 --> 00:39:02.730
as more chemistry can go on. And the

993
00:39:02.730 --> 00:39:04.930
freezing out of the forces and the breaking

994
00:39:04.930 --> 00:39:07.410
of them into other forces seems to be a bit

995
00:39:07.410 --> 00:39:09.810
like that. Now it's way beyond my expertise

996
00:39:09.810 --> 00:39:12.570
and my knowledge. But this is what

997
00:39:12.570 --> 00:39:14.330
happens when you push really at the boundary

998
00:39:14.330 --> 00:39:16.050
of not just what we currently understand and

999
00:39:16.050 --> 00:39:18.250
we know, but what we can possibly observe.

1000
00:39:19.370 --> 00:39:21.570
And so questions like this about the origin

1001
00:39:21.570 --> 00:39:23.810
of the universe, about primordial black holes

1002
00:39:23.810 --> 00:39:26.210
and where they come from, about what the

1003
00:39:26.210 --> 00:39:29.210
conditions were before the Big Bang,

1004
00:39:29.210 --> 00:39:31.250
even though that's meaningless. These are

1005
00:39:31.250 --> 00:39:33.770
really at the limits of what we know and what

1006
00:39:33.770 --> 00:39:35.490
we understand, and they're pushing beyond

1007
00:39:35.490 --> 00:39:37.690
them, but they're also at the limits of what

1008
00:39:37.690 --> 00:39:40.250
we believe that we could ever observe

1009
00:39:40.650 --> 00:39:43.090
if our current models of how everything works

1010
00:39:43.090 --> 00:39:45.370
are correct. And that's always a big caveat,

1011
00:39:45.370 --> 00:39:47.610
because they might turn out not to be. But at

1012
00:39:47.610 --> 00:39:49.730
the minute, the received wisdom seems to be

1013
00:39:49.730 --> 00:39:52.330
that we can never know

1014
00:39:52.570 --> 00:39:54.650
of something earlier than the Big Bang

1015
00:39:54.650 --> 00:39:55.850
because that's when time and space

1016
00:39:55.850 --> 00:39:58.250
originated. We can never know about anything

1017
00:39:58.250 --> 00:40:01.050
outside the universe because the concept of

1018
00:40:01.050 --> 00:40:03.010
space is you can't have an outside, because

1019
00:40:03.410 --> 00:40:05.250
if you were outside, there will be no space

1020
00:40:05.250 --> 00:40:07.010
and therefore you're not. Yeah, it's all a

1021
00:40:07.010 --> 00:40:08.570
bit weird unless.

1022
00:40:08.570 --> 00:40:10.410
Andrew Dunkley: You go down the multiverse part.

1023
00:40:10.410 --> 00:40:12.010
Jonti Horner: Yes, and that's what I was going to say. You

1024
00:40:12.010 --> 00:40:14.250
get some people speculating that you can have

1025
00:40:14.250 --> 00:40:17.250
multiple universes in parallel

1026
00:40:17.250 --> 00:40:19.450
kind of spaces that cannot really strongly

1027
00:40:19.450 --> 00:40:20.730
interact with each other, but where they

1028
00:40:20.730 --> 00:40:22.530
overlap, you might see ripples in the

1029
00:40:22.530 --> 00:40:24.760
microwave background. And so you might see

1030
00:40:24.760 --> 00:40:26.200
some evidence in the structure of our

1031
00:40:26.200 --> 00:40:28.400
universe about the existence of other

1032
00:40:28.400 --> 00:40:30.560
universes that we can't ever touch. But like

1033
00:40:30.560 --> 00:40:32.840
ripples on the surface of water are evidence

1034
00:40:32.840 --> 00:40:35.440
of the wind. You can't see the wind, but you

1035
00:40:35.440 --> 00:40:38.320
can see its effect. So I appreciate. Rob,

1036
00:40:38.320 --> 00:40:40.560
I've probably not got anywhere close to

1037
00:40:40.560 --> 00:40:42.080
answering your question, but what I've done

1038
00:40:42.080 --> 00:40:44.720
instead is explained why I can't. And part of

1039
00:40:44.720 --> 00:40:46.800
that is that I'm not qualified to. I don't

1040
00:40:46.800 --> 00:40:48.720
have the knowledge. But it's also, I think

1041
00:40:48.720 --> 00:40:50.290
you're asked asking questions that

1042
00:40:50.290 --> 00:40:52.510
fundamentally we cannot yet answer and, ah,

1043
00:40:52.510 --> 00:40:55.010
we may never be able to answer. And that's

1044
00:40:55.010 --> 00:40:56.530
why these kind of discussions are fun. It's

1045
00:40:56.530 --> 00:40:57.730
the kind of thing where you sit around a

1046
00:40:57.730 --> 00:41:00.410
campfire and have a couple of drinks or

1047
00:41:00.410 --> 00:41:02.410
whatever and have these deeper, meaningful

1048
00:41:02.410 --> 00:41:03.850
discussions, because it's part of trying to

1049
00:41:03.850 --> 00:41:05.770
understand the entirety of what there is to

1050
00:41:05.770 --> 00:41:06.050
know.

1051
00:41:07.570 --> 00:41:10.010
Andrew Dunkley: Gotcha. Yeah, look, I'm with you there. It's,

1052
00:41:10.010 --> 00:41:12.690
um. How can we know?

1053
00:41:13.250 --> 00:41:14.970
That's the question that comes to my mind

1054
00:41:14.970 --> 00:41:17.690
when I hear a question like Rob's, which I'd

1055
00:41:17.690 --> 00:41:18.770
love to know the answer to.

1056
00:41:19.010 --> 00:41:19.570
Jonti Horner: Me too.

1057
00:41:19.890 --> 00:41:22.690
Andrew Dunkley: How can we possibly know? It's. Yeah,

1058
00:41:23.050 --> 00:41:25.850
um, what, what, what was before the Big

1059
00:41:25.850 --> 00:41:28.670
Bang? What's outside the universe? Um,

1060
00:41:29.330 --> 00:41:31.010
yeah, they're all just

1061
00:41:32.370 --> 00:41:33.090
impossible.

1062
00:41:33.730 --> 00:41:35.929
Jonti Horner: Even beyond that, even if we could get an

1063
00:41:35.929 --> 00:41:37.730
answer, would we be able to understand it? It

1064
00:41:37.730 --> 00:41:40.090
may well think there are answers to this that

1065
00:41:40.090 --> 00:41:41.810
are there, but are so far beyond us at the

1066
00:41:41.810 --> 00:41:43.490
minute that we don't even have the framework

1067
00:41:43.970 --> 00:41:45.490
to formulate those answers.

1068
00:41:47.640 --> 00:41:49.440
Andrew Dunkley: Correct. All right, Rob, thanks for your

1069
00:41:49.440 --> 00:41:50.800
question. Lovely to hear from you.

1070
00:41:50.800 --> 00:41:53.000
Thanks to everyone who contributed to this

1071
00:41:53.000 --> 00:41:55.600
week's Q and A session. If you would like to

1072
00:41:55.600 --> 00:41:58.200
do so, jump on our website SpaceNuts

1073
00:41:58.440 --> 00:42:01.360
IO and click on the AMA link at

1074
00:42:01.360 --> 00:42:04.240
the top. And you can send us a text question

1075
00:42:04.240 --> 00:42:06.040
by giving us your name, your email address

1076
00:42:06.120 --> 00:42:08.440
and uh, putting your message in there. Don't

1077
00:42:08.440 --> 00:42:10.360
forget to tell us who you are or where you're

1078
00:42:10.360 --> 00:42:12.600
from. But if you scroll, uh, down a bit,

1079
00:42:12.950 --> 00:42:15.710
there's the uh, start recording button. If

1080
00:42:15.710 --> 00:42:18.310
you've got a device with a microphone, like

1081
00:42:18.310 --> 00:42:20.470
a, I don't know, a smartphone

1082
00:42:21.110 --> 00:42:23.750
or most computers these days, particularly

1083
00:42:23.750 --> 00:42:25.990
laptops and MacBooks and things like that,

1084
00:42:26.370 --> 00:42:28.470
uh, you can send us an audio question. We'd

1085
00:42:28.470 --> 00:42:30.230
love to get some of those as well. So please

1086
00:42:30.230 --> 00:42:32.190
send them in to us and have a look around on

1087
00:42:32.190 --> 00:42:34.150
our website while you're there. And don't

1088
00:42:34.150 --> 00:42:36.510
forget social media, where, uh, we've got a

1089
00:42:36.510 --> 00:42:39.190
strong presence on Facebook and Instagram

1090
00:42:39.270 --> 00:42:42.160
and the um, the group that was created

1091
00:42:42.160 --> 00:42:45.000
by Space Nuts listeners, the Space Nuts

1092
00:42:45.000 --> 00:42:46.960
podcast group on Facebook.

1093
00:42:48.000 --> 00:42:50.200
Very, uh, much worthwhile joining that group

1094
00:42:50.200 --> 00:42:52.160
and talking amongst each other and solving

1095
00:42:52.160 --> 00:42:53.920
all the problems of the universe, including

1096
00:42:54.000 --> 00:42:56.719
Rob's probably. Uh, so, yeah,

1097
00:42:57.040 --> 00:42:58.800
check um, it out. Just do a search for Space

1098
00:42:58.800 --> 00:43:01.520
Nuts on Facebook or Space Nuts podcast group.

1099
00:43:02.230 --> 00:43:03.760
Uh, they're both there. Both have,

1100
00:43:05.270 --> 00:43:07.520
um, thousands upon thousands of followers. So

1101
00:43:07.680 --> 00:43:10.460
it's fantastic. Love it. Uh, and

1102
00:43:10.460 --> 00:43:12.420
Jonti, we are done. Thank you so much for

1103
00:43:12.420 --> 00:43:14.100
tackling all of that. They were some pretty

1104
00:43:14.100 --> 00:43:15.900
curly questions, especially the spaghetti

1105
00:43:15.900 --> 00:43:17.100
one. Lots of curls in that.

1106
00:43:18.060 --> 00:43:19.420
Jonti Horner: Make me hungry as well.

1107
00:43:19.740 --> 00:43:22.460
Andrew Dunkley: Yes, yes, I had spaghetti for dinner earlier.

1108
00:43:22.460 --> 00:43:24.779
In fact, uh, we'll catch you next time.

1109
00:43:24.779 --> 00:43:26.140
Jonti, thank you so much.

1110
00:43:26.300 --> 00:43:27.860
Jonti Horner: It's a pleasure. Thank you and awesome

1111
00:43:27.860 --> 00:43:29.580
questions. Really enjoyed it. Even if my head

1112
00:43:29.580 --> 00:43:30.220
now hurts.

1113
00:43:31.580 --> 00:43:34.380
Andrew Dunkley: You can take something for that. Uh, and,

1114
00:43:34.470 --> 00:43:36.460
uh, thank you for, for listening. Don't

1115
00:43:36.460 --> 00:43:39.100
forget, uh, to, um. Yeah, as I said, uh, send

1116
00:43:39.100 --> 00:43:41.680
your questions in via our. And thanks to Huw

1117
00:43:41.680 --> 00:43:43.640
in the studio, who couldn't be with us today

1118
00:43:43.640 --> 00:43:45.480
because he and his wife were having a big

1119
00:43:46.280 --> 00:43:48.840
night out, which is terrific and they deserve

1120
00:43:48.840 --> 00:43:50.760
it. And from me, Andrew Dunkley, thanks for

1121
00:43:50.760 --> 00:43:52.840
your company. Catch you on the next episode

1122
00:43:52.840 --> 00:43:55.000
of Space Nuts. Bye. Bye.

1123
00:43:56.120 --> 00:43:58.320
Jonti Horner: You'll be listening to the Space Nuts

1124
00:43:58.320 --> 00:44:01.280
podcast, available at

1125
00:44:01.280 --> 00:44:03.240
Apple Podcasts, Spotify,

1126
00:44:03.480 --> 00:44:06.140
iHeartRadio or your favorite podcast

1127
00:44:06.370 --> 00:44:07.970
player. You can also stream on

1128
00:44:07.970 --> 00:44:09.650
demand@bytes.com.

1129
00:44:09.970 --> 00:44:12.050
Andrew Dunkley: This has been another quality podcast

1130
00:44:12.050 --> 00:44:14.130
production from bytes.um com.