WEBVTT - Listener Questions 68

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<v Speaker 1>Hey, Daniel, So, who do you think is going to

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<v Speaker 1>figure out the secrets of the universe? Is there, like

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<v Speaker 1>somebody that you you know or have been keeping your

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<v Speaker 1>eye on?

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<v Speaker 2>Oh? Man, I wish I knew the answer to that question.

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<v Speaker 1>Well, but like, do you think it's someone we already

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<v Speaker 1>know about, like a smart person like Lisa Randall or

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<v Speaker 1>Ed Witten.

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<v Speaker 2>It could be, but my money is on somebody smart,

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<v Speaker 2>somebody young, maybe somebody who's listening to this podcast right now.

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<v Speaker 1>Whoa so like, how would you feel if it turned

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<v Speaker 1>out that, like the big questions weren't answered by you,

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<v Speaker 1>but you were upstaged by some like ten year old

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<v Speaker 1>after you failed for decades.

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<v Speaker 2>After failing for decades, I would be relieved if somebody

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<v Speaker 2>else came along to figure this stuff out for us.

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<v Speaker 1>I feel like that's that's the right answer. The answer

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<v Speaker 1>matters more than the person. Love it.

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<v Speaker 2>Hi. I'm Daniel. I'm a particle physicist and a professor

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<v Speaker 2>at UC Irvine, and I just desperately want the answers.

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<v Speaker 1>I'm Kelly Wienersmith. I'm a parasitologist at Race University, and

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<v Speaker 1>I also desperately want the answers. But the questions need

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<v Speaker 1>to be about parasites, and.

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<v Speaker 2>You're also the Hugo Award winning author of a nonfiction book. Congratulations.

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<v Speaker 1>Thanks. I'll try to not scream too loud that the

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<v Speaker 1>trophy arrived, and I am still losing my mind every

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<v Speaker 1>time I look at it. I cannot believe that that happened.

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<v Speaker 1>But I also can believe that Zach didn't prepare an

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<v Speaker 1>acceptance speech, even though the flight to Glasgow takes like

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<v Speaker 1>eight hours. He just assumed we weren't going to win,

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<v Speaker 1>so he prepared nothing and I almost killed him.

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<v Speaker 2>Oh well, well, I'm sure his spontaneous speech was even

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<v Speaker 2>better than anything he could have written. It was fine,

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<v Speaker 2>but I wanted all of you out there to appreciate it.

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<v Speaker 2>Kelly is not just one of the hosts on this podcast,

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<v Speaker 2>but she's actually an award winning best selling science writer,

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<v Speaker 2>so we're grateful to have her here. Thanks very much

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<v Speaker 2>for joining us.

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<v Speaker 1>Oh you're the best. Thanks Daniel, I love being.

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<v Speaker 2>Here, and welcome to the podcast. Daniel and Jorge Explain

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<v Speaker 2>the Universe, a production of iHeartRadio in which we explore

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<v Speaker 2>everything about the universe. It's ups and its downs, it's

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<v Speaker 2>lefts and its rights, the things that wins the awards

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<v Speaker 2>for and the things that drive physicists crazy. Hopeful that

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<v Speaker 2>somebody young out there will figure it all out for.

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<v Speaker 1>Us as soon as possible. Guys get on.

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<v Speaker 2>It, and as part of that process, we want you

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<v Speaker 2>to be thinking about the nature of the universe. Yes,

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<v Speaker 2>you are relaxing as you fall asleep, or you are

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<v Speaker 2>commuting to work and hoping to be educated and entertained,

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<v Speaker 2>but this podcast also requires you to do some work

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<v Speaker 2>to fit all these ideas into your head and to

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<v Speaker 2>write to us when they don't quite click together. If

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<v Speaker 2>you have a question about the nature of the universe,

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<v Speaker 2>we want to hear it. That's part of the progress

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<v Speaker 2>of science. Everybody out there wondering and thinking and trying

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<v Speaker 2>to figure this stuff out. So please send me your

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<v Speaker 2>questions to questions at Daniel and Jorge dot com. You

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<v Speaker 2>will definitely hear back from us, and sometimes we choose

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<v Speaker 2>those questions to answer or write here on the podcast.

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<v Speaker 1>And sometimes the questions that you get from people new

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<v Speaker 1>to the field are way better than any question you

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<v Speaker 1>get at a department seminar with a bunch of pros

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<v Speaker 1>in the field, because, like you're not constrained by all

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<v Speaker 1>the assumptions that people who have been in the field

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<v Speaker 1>for a while have. So we get some pretty great

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<v Speaker 1>questions from the listeners.

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<v Speaker 2>Yes, absolutely we do, and we get questions that I

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<v Speaker 2>don't anticipate, and so I hope that these questions line

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<v Speaker 2>up with your questions. That these ones we've chosen are

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<v Speaker 2>also questions that other folks out there have and want

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<v Speaker 2>to hear the answer to. So please don't be shy.

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<v Speaker 2>If you're thinking of a question, somebody else also wants

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<v Speaker 2>to hear the answer, and I need somebody to write

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<v Speaker 2>in and send it to me. So please don't be shy.

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<v Speaker 2>I love hearing from all of you.

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<v Speaker 1>Please keep Daniel company, guys.

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<v Speaker 2>And so today on the podcast, we'll be answering listener

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<v Speaker 2>questions number sixty eight who and we are featuring a

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<v Speaker 2>question from a young future physicist, Clara from Germany. So,

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<v Speaker 2>without further ado, here's Clara's question.

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<v Speaker 3>Hello and Clara from Germany, twelve years old and you

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<v Speaker 3>listen of your podcast. My question is could it be

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<v Speaker 3>possible that the universe is finite in one direction and

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<v Speaker 3>incident and all the others? Your podcast is just writing

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<v Speaker 3>you two guys can explain so well.

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<v Speaker 1>Thanks Clara, So, Daniel, when I was twelve years old,

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<v Speaker 1>I was sequestered in my bedroom listening to Silverchair and

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<v Speaker 1>playing the first three chords to smells like teen Spirit

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<v Speaker 1>by Nirvana, but not bothering to learn any the rest

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<v Speaker 1>of the song. I was not pondering the nature of

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<v Speaker 1>the universe. So good on you, Clara. What were you

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<v Speaker 1>doing when you were twelve, Daniel.

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<v Speaker 2>I was reading a lot of science fiction and a

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<v Speaker 2>lot of fantasy, and I definitely was pondering the nature

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<v Speaker 2>of the universe. I remember trying to think about whether

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<v Speaker 2>space was in three dimensions everywhere, or maybe parts of

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<v Speaker 2>the universe might have additional dimensions, and really struggling to

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<v Speaker 2>get my mind around what that meant and what would

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<v Speaker 2>be like to exist in those dimensions. So, yeah, Clara

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<v Speaker 2>and I have a lot in common. Good job, Clara.

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<v Speaker 1>Well some of us are late blossoming nerds, I guess.

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<v Speaker 1>But what we get there eventually, So give us some

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<v Speaker 1>background on what we knew about this question so far, Daniel.

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<v Speaker 2>Yeah, Clara's question touches on two really important ideas, and

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<v Speaker 2>she's doing something I love, which is trying to bring

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<v Speaker 2>two ideas together. You know, physics is about unification of

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<v Speaker 2>your understanding. It's not like chemistry where you use this

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<v Speaker 2>equation over here and that equation over there, and it's

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<v Speaker 2>just like these patches of understanding and physics. We hope

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<v Speaker 2>to have a complete cloth, you know, to stitch everything

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<v Speaker 2>together into one idea. So it's really important that when

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<v Speaker 2>you hear or related ideas, you try to understand how

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<v Speaker 2>they fit together. And that's what she's doing here and here.

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<v Speaker 2>The related ideas are about the size and the scope

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<v Speaker 2>of the universe, like is the universe infinite or is

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<v Speaker 2>the universe finite? And when you just imagine space and

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<v Speaker 2>the whole universe, you probably just fill your mind with blackness,

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<v Speaker 2>and you imagine that it goes on forever. That you

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<v Speaker 2>could shoot a laser beam and it would just fly

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<v Speaker 2>on forever and ever until it hits something. But if

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<v Speaker 2>the universe was empty, it would just go on forever.

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<v Speaker 2>You can imagine these like dotted lines of x, y,

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<v Speaker 2>and z dimensions just stretching out to infinity, limited only

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<v Speaker 2>by your imagination. That's an infinite universe. And we don't

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<v Speaker 2>know if the universe is infinite, but such an infinite universe,

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<v Speaker 2>though it's a little bit weird to hold in your mind.

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<v Speaker 2>Is actually one of the most natural ideas for how

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<v Speaker 2>the universe might be shaped.

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<v Speaker 1>Is this a question that you think will have an

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<v Speaker 1>answer to in your lifetime or what will we be

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<v Speaker 1>wondering if the universe is finite or infinite three hundred

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<v Speaker 1>years from now?

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<v Speaker 2>Wow? Awesome. It's hard to prove that the universe is

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<v Speaker 2>infinite because if it goes on forever, then you need

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<v Speaker 2>infinite data to prove that. But we might be able

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<v Speaker 2>to prove the opposite. We might be able to prove

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<v Speaker 2>that it's not infinite because you could discover that the

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<v Speaker 2>universe is finite because the extent of the universe is

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<v Speaker 2>connected to another question about the shape of the universe,

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<v Speaker 2>Like if the universe is flat, and by flat, we

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<v Speaker 2>don't mean like a two D sheet of paper, We

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<v Speaker 2>mean the two parallel lines will not cross. It's a

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<v Speaker 2>three dimensional version of flatness. But if the universe is curved,

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<v Speaker 2>so the two parallel lines either diverge or do cross

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<v Speaker 2>over each other, and again curved in three dimensions in

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<v Speaker 2>a sort of general relative VisiC sort of way. That

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<v Speaker 2>means that the universe could be finite, that it could

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<v Speaker 2>loop around on itself again in a weird three dimensional way,

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<v Speaker 2>not exactly the same, like the surface of a sphere

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<v Speaker 2>loops around on itself, but in analogy to that. So,

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<v Speaker 2>if we discover that space is curved, that suggests the

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<v Speaker 2>space might be finite, and so we can't prove that

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<v Speaker 2>it's infinite, but we might discover that it is finite.

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<v Speaker 1>WHOA, I feel like I'm lost in thought here. So

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<v Speaker 1>if it's curved, then what's on the other side of

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<v Speaker 1>the curve.

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<v Speaker 2>No, this is a big mental pothole that we should

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<v Speaker 2>totally address, because if you imagine the universe as finite

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<v Speaker 2>and curved, you probably have in your mind something like

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<v Speaker 2>a sphere, a ball.

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<v Speaker 1>Right, I'm thinking of a doughnut because I'm hungry, all right.

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<v Speaker 2>It could also be a donut, right, But the problem is,

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<v Speaker 2>as soon as you name some object like that, you

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<v Speaker 2>imagine it with its boundaries inside some other vast mental space.

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<v Speaker 2>Like if I close my eyes and I think of

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<v Speaker 2>a donut, it's hovering in some blackness, and that's a mistake.

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<v Speaker 2>I've like sketched around it some empty space. But when

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<v Speaker 2>we talk about the universe as finite, we don't mean

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<v Speaker 2>like there's a bunch of stuff, and around it is

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<v Speaker 2>empty space. We mean finite including I mean, that's all

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<v Speaker 2>there is. Don't sketch anything around it. Don't fill in

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<v Speaker 2>that mental space with something. The finite universe is limited

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<v Speaker 2>in size, but it doesn't have an edge of boundary.

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<v Speaker 2>Every point on it is exactly the same. It's very,

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<v Speaker 2>very difficult to think about. It's very counterintuitive.

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<v Speaker 1>Yeah, I feel like the world is split into people

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<v Speaker 1>who think that that's fun and people who just are

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<v Speaker 1>really frustrated. There might be a different camps there.

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<v Speaker 2>So we should get to Claria's question, but first we

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<v Speaker 2>have to take a quick break.

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<v Speaker 1>What do we think let's follow up on Clara's idea.

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<v Speaker 2>Yeah, so Claren's question is porque Nola's does, right. She's like,

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<v Speaker 2>why can't it be infinite and finite? And she's saying,

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<v Speaker 2>what if you have a few dimensions in which it's infinite,

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<v Speaker 2>but other dimensions in which it's finite. So imagine, for example,

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<v Speaker 2>like an infinite cylinder. In one dimension it goes on forever,

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<v Speaker 2>but in the other dimensions it's limited. You know, it's

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<v Speaker 2>like a centimeter wide or a meter wide or something.

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<v Speaker 2>So you can picture geometric shapes which are like this,

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<v Speaker 2>that are infinite in one dimension and finite in others.

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<v Speaker 2>And she's basically asking, could our universe be like that?

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<v Speaker 2>Could it have two different kinds of dimensions, some that

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<v Speaker 2>are infinite and some that are finite.

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<v Speaker 1>Are there any current theories that encapsulate that, Like, has

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<v Speaker 1>she identified a theory that physicists are working with right

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<v Speaker 1>now as far as you know, or is this a

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<v Speaker 1>totally new way of thinking about it?

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<v Speaker 2>Claire's actually thought her way into a very popular area

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<v Speaker 2>of research right now, because it's totally possible to have

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<v Speaker 2>a geometry of the universe where you have some infinite

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<v Speaker 2>dimensions and some finite there's no theoretical reason saying you

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<v Speaker 2>can't do that. And first let's talk about like how

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<v Speaker 2>to try, frustratingly to visualize that your mind, and then

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<v Speaker 2>let's talk about why theorists are excited about this kind

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<v Speaker 2>of idea. So we know that there are three dimensions

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<v Speaker 2>in our universe X, y, and z. These are the

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<v Speaker 2>normal spatial dimensions, and let's just say those are infinite,

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<v Speaker 2>that they go on forever. If you shine a laser

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<v Speaker 2>beam out into space, if you don't hit some other

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<v Speaker 2>galaxy or some alien eyeball, it's just going to go

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<v Speaker 2>on forever, and if you shine two, they're going to

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<v Speaker 2>be in parallel forever. Right, So that's infinite flat space. Okay,

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<v Speaker 2>so hold that in your mind. Now we want to

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<v Speaker 2>add a fourth dimension, and we don't want to add

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<v Speaker 2>a fourth infinite dimension some new direction you could shoot

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<v Speaker 2>your laser beam, which is already very difficult to put

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<v Speaker 2>into your three D mental space. Let's add a fourth

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<v Speaker 2>finite dimension. And so the sort of two mental ways

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<v Speaker 2>to visualize this one is take your three D infinite

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<v Speaker 2>space and at every point, replace that point with a loop,

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<v Speaker 2>like a little circle, you know, like a bracelet.

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<v Speaker 1>Essentially, I'm getting angry, you're getting angry. I'm kidding. Let's

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<v Speaker 1>go forward, all right, lots of loops in infinite space, yes, exactly.

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<v Speaker 2>So instead of space being filled with points, now it's

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<v Speaker 2>filled with loops. And where you are along that loop

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<v Speaker 2>is essentially the fourth dimension. So now you have like

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<v Speaker 2>four numbers in your address, three numbers to tell you

0:12:17.800 --> 0:12:20.120
<v Speaker 2>where you are in the usual three D space, and

0:12:20.200 --> 0:12:22.800
<v Speaker 2>one to tell you how far you are along this loop.

0:12:23.000 --> 0:12:24.880
<v Speaker 2>So now space is like more complex.

0:12:25.320 --> 0:12:29.200
<v Speaker 1>Is there a way to help me picture that? Like

0:12:29.200 --> 0:12:31.080
<v Speaker 1>like I move in a direction and I get stuck

0:12:31.120 --> 0:12:33.040
<v Speaker 1>in a loop, and it's like being in a whirlpool.

0:12:33.320 --> 0:12:36.120
<v Speaker 1>Or is that extra dimension time and it determines how

0:12:36.160 --> 0:12:36.880
<v Speaker 1>long I'm there?

0:12:37.559 --> 0:12:40.960
<v Speaker 2>The extra dimension is not time, it's space, right, okay,

0:12:41.040 --> 0:12:44.000
<v Speaker 2>And you could still move through three D space jumping

0:12:44.040 --> 0:12:46.280
<v Speaker 2>from loop to loop the same way you can, like

0:12:46.559 --> 0:12:50.000
<v Speaker 2>move only in X without changing your y value. An

0:12:50.040 --> 0:12:53.000
<v Speaker 2>alternative way to think about it, instead of an infinite

0:12:53.000 --> 0:12:55.839
<v Speaker 2>space filled with loops is to take a single loop

0:12:55.960 --> 0:12:58.640
<v Speaker 2>and at every point put infinite space in it. So

0:12:58.720 --> 0:13:03.520
<v Speaker 2>imagine like a big loop of infinite spaces instead of

0:13:03.559 --> 0:13:06.280
<v Speaker 2>an infinite space of loops. It doesn't really matter which

0:13:06.400 --> 0:13:09.120
<v Speaker 2>order you think about it. Geometrically, it's the same, and

0:13:09.200 --> 0:13:11.280
<v Speaker 2>both of them will give you a migraine because it's

0:13:12.520 --> 0:13:15.880
<v Speaker 2>about four dimensions at all, But that's my best thing.

0:13:18.760 --> 0:13:21.960
<v Speaker 2>Especially in an audio format. This is challenging to describe,

0:13:22.400 --> 0:13:24.719
<v Speaker 2>but the bottom line is, yes, Claire, it's possible to

0:13:24.760 --> 0:13:28.239
<v Speaker 2>build a geometry where space is finite in some dimensions

0:13:28.240 --> 0:13:31.480
<v Speaker 2>and infinite in others. And this is actually very exciting

0:13:31.520 --> 0:13:35.040
<v Speaker 2>theoretically because it might explain one of the open puzzles

0:13:35.160 --> 0:13:38.880
<v Speaker 2>in physics, which is why gravity is so much weaker

0:13:38.920 --> 0:13:41.600
<v Speaker 2>than the other forces. Like, if you think of gravity

0:13:41.600 --> 0:13:44.080
<v Speaker 2>as a force, we know that it's much much weaker

0:13:44.120 --> 0:13:46.360
<v Speaker 2>than all the other forces out there. And like the

0:13:46.400 --> 0:13:48.920
<v Speaker 2>canonical example is that you can hold up a paper

0:13:48.920 --> 0:13:52.520
<v Speaker 2>clip using a kitchen magnet, which is counteracting the entire

0:13:52.559 --> 0:13:56.400
<v Speaker 2>gravitational force of the Earth, right, a huge mass or

0:13:56.559 --> 0:13:59.080
<v Speaker 2>you know, like a toddler's legs are strong enough to

0:13:59.200 --> 0:14:02.240
<v Speaker 2>overcome the groundravity of the Earth and learn to jump.

0:14:02.440 --> 0:14:03.520
<v Speaker 2>That's electromechanical.

0:14:03.679 --> 0:14:07.280
<v Speaker 1>And they're so cute and squishy, I know, and.

0:14:07.200 --> 0:14:10.280
<v Speaker 2>They're defeating an entire planet's gravity. Right. So gravity is

0:14:10.320 --> 0:14:13.599
<v Speaker 2>a crazy weak force, and that's a puzzle for physicists

0:14:13.600 --> 0:14:15.520
<v Speaker 2>because we like things to be in balance. We like

0:14:15.840 --> 0:14:18.960
<v Speaker 2>to understand why things are out of balance if they are.

0:14:19.600 --> 0:14:23.280
<v Speaker 2>So the explanation is, maybe the reason gravity is weak

0:14:23.680 --> 0:14:26.880
<v Speaker 2>is because it's special. Maybe the universe has a bunch

0:14:26.920 --> 0:14:30.480
<v Speaker 2>of other dimensions. But like Claria suggests, their loops and

0:14:30.520 --> 0:14:33.920
<v Speaker 2>their small little dimensions, their loops are like a centimeter

0:14:34.040 --> 0:14:37.000
<v Speaker 2>or even a millimeter or even smaller. And so what

0:14:37.120 --> 0:14:40.840
<v Speaker 2>happens is that gravity actually isn't weaker than the other forces.

0:14:40.880 --> 0:14:43.560
<v Speaker 2>It's just the same strength, but it feels weaker to

0:14:43.680 --> 0:14:46.640
<v Speaker 2>us because at distances bigger than a centimeter or bigger

0:14:46.680 --> 0:14:49.440
<v Speaker 2>than these dimensions, it's already sort of bled out into

0:14:49.440 --> 0:14:53.000
<v Speaker 2>these other dimensions. It spreads out in these other dimensions,

0:14:53.000 --> 0:14:55.880
<v Speaker 2>and so it seems weak to us. So that's like

0:14:55.920 --> 0:15:00.480
<v Speaker 2>a cool explanation for another puzzle in particle physics, if

0:15:00.520 --> 0:15:04.080
<v Speaker 2>we could prove that the universe did have additional dimensions

0:15:04.400 --> 0:15:05.440
<v Speaker 2>that were finite.

0:15:05.640 --> 0:15:08.320
<v Speaker 1>So one of my favorite parts of doing science is

0:15:08.360 --> 0:15:13.600
<v Speaker 1>designing experiments. Is there an experiment you could design to test, like,

0:15:13.640 --> 0:15:16.520
<v Speaker 1>for example, to look for those loops? Or this is

0:15:16.600 --> 0:15:18.240
<v Speaker 1>just too hard because it's all too big and it

0:15:18.280 --> 0:15:19.080
<v Speaker 1>goes on too long.

0:15:19.480 --> 0:15:21.920
<v Speaker 2>No, there absolutely is an experiment, but you're not gonna

0:15:21.960 --> 0:15:22.200
<v Speaker 2>like it.

0:15:23.720 --> 0:15:26.200
<v Speaker 1>You don't know me, but you probably know me well enough.

0:15:26.240 --> 0:15:27.800
<v Speaker 1>I'm probably not gonna like it, but go for it.

0:15:27.800 --> 0:15:28.040
<v Speaker 1>Tell me.

0:15:28.320 --> 0:15:30.760
<v Speaker 2>I mean it might destroy the planet. So if you're

0:15:30.760 --> 0:15:33.000
<v Speaker 2>cool with that, then yeah.

0:15:32.560 --> 0:15:34.480
<v Speaker 1>No, No, my kids are on this planet. You know

0:15:34.520 --> 0:15:36.840
<v Speaker 1>how I feel about when you endanger my kids.

0:15:37.720 --> 0:15:40.000
<v Speaker 2>So the idea is to do an experiment that tests

0:15:40.080 --> 0:15:44.120
<v Speaker 2>whether gravity gets really strong when things get close together.

0:15:44.560 --> 0:15:46.560
<v Speaker 2>And one way you can do that is try to

0:15:46.600 --> 0:15:49.480
<v Speaker 2>just measure the gravity of things that are really close together,

0:15:50.000 --> 0:15:52.640
<v Speaker 2>Like take two balls and put them a millimeter apart

0:15:52.720 --> 0:15:54.960
<v Speaker 2>and measure their gravity. This turns out to be really,

0:15:55.040 --> 0:15:57.920
<v Speaker 2>really hard because gravity is so weak and anything you

0:15:58.040 --> 0:16:01.040
<v Speaker 2>build is going to have really weak rindsvity. And there's

0:16:01.040 --> 0:16:04.360
<v Speaker 2>some real experimental virtuoso's at University of Washington who've been

0:16:04.360 --> 0:16:07.160
<v Speaker 2>doing these kinds of experiments and it's really amazing. They

0:16:07.200 --> 0:16:10.720
<v Speaker 2>have to isolate it from like anytime somebody coughs three

0:16:10.720 --> 0:16:13.280
<v Speaker 2>blocks away, or like a dog wags its tail and

0:16:13.400 --> 0:16:17.520
<v Speaker 2>changes the airflow or whatever. It's ridiculous what they have

0:16:17.560 --> 0:16:19.680
<v Speaker 2>to buffer themselves against because they're looking for such a

0:16:19.680 --> 0:16:23.040
<v Speaker 2>tiny effect. On the other hand, we can also do

0:16:23.160 --> 0:16:26.840
<v Speaker 2>it at the Large Hadron Collider because if gravity gets

0:16:26.880 --> 0:16:29.600
<v Speaker 2>really powerful when things get close together, Hey, that's what

0:16:29.600 --> 0:16:31.640
<v Speaker 2>we do all day. We take protons, we put them

0:16:31.640 --> 0:16:35.520
<v Speaker 2>really close together. And so the idea is maybe sometimes

0:16:35.520 --> 0:16:38.560
<v Speaker 2>when protons get really close together, their gravity gets really

0:16:38.600 --> 0:16:42.000
<v Speaker 2>strong and they make a tiny black hole. And so

0:16:42.160 --> 0:16:45.160
<v Speaker 2>these extra dimensions could enhance the power of gravity at

0:16:45.160 --> 0:16:48.080
<v Speaker 2>short distances and give us a chance to make more

0:16:48.080 --> 0:16:51.680
<v Speaker 2>black holes than we otherwise could, maybe even seeing one

0:16:51.680 --> 0:16:54.760
<v Speaker 2>evaporate in our detector and of course not destroying the

0:16:54.800 --> 0:16:57.400
<v Speaker 2>earth and keeping Kelly's children alive and healthy.

0:16:57.640 --> 0:17:00.600
<v Speaker 1>Thank you my children in particular. And so if we're

0:17:00.600 --> 0:17:05.159
<v Speaker 1>worried about dimensions, does creating a black hole is that,

0:17:06.240 --> 0:17:09.040
<v Speaker 1>you know, sort of analogous to the loops in the

0:17:09.080 --> 0:17:10.760
<v Speaker 1>dimensions that you were talking about, the.

0:17:10.680 --> 0:17:13.400
<v Speaker 2>Black hole, if it exists, would also exist in those

0:17:13.480 --> 0:17:16.879
<v Speaker 2>other dimensions. But ideas that those dimensions also weaken the

0:17:16.920 --> 0:17:20.000
<v Speaker 2>gravity for things that are further apart than the size

0:17:20.040 --> 0:17:22.520
<v Speaker 2>of those dimensions, and so you can create a black

0:17:22.520 --> 0:17:25.520
<v Speaker 2>hole by getting things really really close. That's sort of

0:17:25.520 --> 0:17:27.680
<v Speaker 2>the idea. We've never seen a black hole the large

0:17:27.720 --> 0:17:31.120
<v Speaker 2>Adron collider, so we have no experimental proof of any

0:17:31.160 --> 0:17:34.760
<v Speaker 2>of these additional spatial dimensions. There's another way you could

0:17:34.760 --> 0:17:36.880
<v Speaker 2>look for them, which is to look for weird echos

0:17:36.960 --> 0:17:40.000
<v Speaker 2>of the particles that we have seen. Like if the

0:17:40.080 --> 0:17:43.240
<v Speaker 2>electron exists in our universe, there might be an echo

0:17:43.400 --> 0:17:46.359
<v Speaker 2>of the electron in which it's like vibrating in this

0:17:46.400 --> 0:17:49.000
<v Speaker 2>additional dimension, and so it would look like an electron

0:17:49.280 --> 0:17:52.120
<v Speaker 2>but with more mass, like a heavier version of the electron,

0:17:52.680 --> 0:17:55.160
<v Speaker 2>and because of resonance effects, you would get a bunch

0:17:55.160 --> 0:17:57.199
<v Speaker 2>of these, you would get like one that's heavier, and

0:17:57.200 --> 0:17:59.280
<v Speaker 2>when that's twice is heavy and three times is heavy,

0:17:59.440 --> 0:18:02.919
<v Speaker 2>you get this whole tower of weird heavy electrons. So

0:18:02.960 --> 0:18:05.840
<v Speaker 2>we've looked for those and haven't seen them. So yes,

0:18:05.960 --> 0:18:08.560
<v Speaker 2>we can look for these things. No, we have no

0:18:08.720 --> 0:18:13.159
<v Speaker 2>evidence that the universe does have additional finite dimensions on

0:18:13.280 --> 0:18:17.360
<v Speaker 2>top of the three probably infinite dimensions that we know about.

0:18:17.440 --> 0:18:23.199
<v Speaker 1>And finding another dimension doesn't immediately answer the question. Is

0:18:23.240 --> 0:18:26.840
<v Speaker 1>the universe finite in one direction and infinite in the other, Right,

0:18:26.880 --> 0:18:29.359
<v Speaker 1>you'd still need additional information, that's just part of it.

0:18:29.640 --> 0:18:31.960
<v Speaker 2>Yeah, that's right. First step is discover the other dimension.

0:18:31.960 --> 0:18:34.880
<v Speaker 2>Second is to measure the curvature of that dimension. If

0:18:34.920 --> 0:18:37.320
<v Speaker 2>it's highly curved, then it probably is a loop. Then

0:18:37.359 --> 0:18:40.880
<v Speaker 2>it probably is finite. Clara wins the Nobel Prize. If

0:18:40.920 --> 0:18:43.159
<v Speaker 2>it turns out to be infinite, then like that blows

0:18:43.200 --> 0:18:45.960
<v Speaker 2>our minds in a whole other way. Like another infinite

0:18:46.000 --> 0:18:47.280
<v Speaker 2>dimension in our universe.

0:18:47.280 --> 0:18:50.440
<v Speaker 1>That would be crazy or infuriating.

0:18:51.920 --> 0:18:53.080
<v Speaker 2>Or headache inducing.

0:18:55.200 --> 0:18:56.320
<v Speaker 1>Now it would be cool.

0:18:56.520 --> 0:18:59.520
<v Speaker 2>All right, So that's the answer for Clara. Yes, the

0:18:59.640 --> 0:19:04.520
<v Speaker 2>universe could have finite and infinite dimensions. At the same time,

0:19:04.880 --> 0:19:07.280
<v Speaker 2>as much as that's difficult to think about, and while

0:19:07.280 --> 0:19:10.280
<v Speaker 2>we are doing experiments to search for these additional dimensions,

0:19:10.320 --> 0:19:13.199
<v Speaker 2>we do not yet have any evidence that they exist.

0:19:13.200 --> 0:19:14.879
<v Speaker 2>But we're going to keep looking to hope to provide

0:19:14.920 --> 0:19:16.639
<v Speaker 2>Clara with the Nobel Prize in the future.

0:19:17.880 --> 0:19:19.760
<v Speaker 1>Yeah, thank you for this amazing question.

0:19:19.840 --> 0:19:22.840
<v Speaker 2>And thanks to everybody out there who thinks about the universe,

0:19:23.000 --> 0:19:26.240
<v Speaker 2>wonders about it, wants to understand it, and writes to us.

0:19:26.359 --> 0:19:29.640
<v Speaker 2>Send us your questions to questions at dangelan Jorge dot com.

0:19:29.840 --> 0:19:32.880
<v Speaker 2>Everybody gets an answer and some people get highlighted on

0:19:32.920 --> 0:19:33.600
<v Speaker 2>the podcast.

0:19:33.760 --> 0:19:35.520
<v Speaker 1>Woo, it's like getting a hugo.

0:19:39.160 --> 0:19:41.480
<v Speaker 2>Yes, you can put it on your CP for sure.

0:19:42.800 --> 0:19:44.919
<v Speaker 2>All right, Thanks very much Kelly for helping me answer

0:19:44.960 --> 0:19:45.680
<v Speaker 2>these questions.

0:19:45.760 --> 0:19:47.159
<v Speaker 1>Thanks so much for having me on the show. It

0:19:47.160 --> 0:19:48.320
<v Speaker 1>was a lot of fun, all right.

0:19:48.359 --> 0:19:56.360
<v Speaker 2>Everyone, tune in next time for more science and curiosity.

0:19:56.359 --> 0:19:59.240
<v Speaker 2>Come find us on social media where we answer questions

0:19:59.280 --> 0:20:03.680
<v Speaker 2>and post video. We're on Twitter, Discorg, Insta, and now TikTok.

0:20:04.400 --> 0:20:07.200
<v Speaker 2>Thanks for listening, and remember that Daniel and Jorge Explain

0:20:07.280 --> 0:20:11.280
<v Speaker 2>the Universe is a production of iHeartRadio. For more podcasts

0:20:11.280 --> 0:20:15.920
<v Speaker 2>from iHeartRadio, visit the iHeartRadio app, Apple podcasts, or wherever

0:20:16.000 --> 0:20:17.719
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