Cosmic Queries: Time and Higher Dimensions

Neil deGrasse Tyson, mathematician John Allen Paulos, physicist James Kakalios, and comic co-host Harrison Greenbaum investigate the fourth dimension, hypercubes, wormholes, Edwin Abbott’s “Flatland,” and much more! NOTE: StarTalk All-Access subscribers can watch or listen to this entire episode commercial-free: https://www.startalkradio.net/all-access/cosmic-queries-time-and-higher-dimensions/

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Neil deGrasse Tyson?

  Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now.

• 0:21Neil deGrasse Tyson?

  Welcome to StarTalk. I'm your host Neil deGrasse Tyson, your personal astrophysicist. And today's topic is on higher dimensions in space and in time. And for that, I have a new co-host Harrison Greenbaum. Harrison, welcome to StarTalk. I'm very excited. Where have you been all our life? I've been around in another dimension, watching you guys. That's what it was. It was another dimension. Glad to have you. And I hope this topic is something you feel good about. Absolutely. Okay, because even if you don't, I got somebody else, just in case. Okay, cool, perfect. Let me introduce an old time friend. It's John Allen Paulos. He's a professor of mathematics at Temple University over there in Philadelphia.

• 1:06Neil deGrasse Tyson?

  Philadelphia. There you go. He's written some books, most recently A Numerate Life. Sounds very autobiographical. Is that correct?

• 1:15Speaker 01

  It's a mixture of math and memoir.

• 1:17Neil deGrasse Tyson?

  Math. Oh, I like that. Math and memoir. That's beautiful. And Harrison, you're tweeting at Harrison Comic.

• 1:23Harrison Greenbaum?

  Harrison Comedy.

• 1:24Neil deGrasse Tyson?

  Harrison Comedy.

• 1:25Harrison Greenbaum?

  Yes.

• 1:26Neil deGrasse Tyson?

  Well, we'll.

• 1:26Harrison Greenbaum?

  Oh, yeah. Tens and tens of people read it.

• 1:28Neil deGrasse Tyson?

  Tens and tens.

• 1:30Harrison Greenbaum?

  Oh, yeah. Killing it.

• 1:31Neil deGrasse Tyson?

  So, so, so John, I called you on to the show because we always get questions because part of the show is going to be cosmic queries. And we always get questions about dimensions, sometimes informed by movies that people saw. And but there's other things about dimensions that I think are just awesome, that people wouldn't even necessarily know to ask. And I brought you in because you're my, you're my mathematician at arm's reach. Harrison, do you have your own mathematician?

• 2:02Harrison Greenbaum?

  I have a calculator on my phone.

• 2:07Neil deGrasse Tyson?

  Close, but I think everybody should have a mathematician at our reach.

• 2:09Harrison Greenbaum?

  I was a psych major. We had our own statistics. We had psych for statistics for psych, which was not as.

• 2:15Neil deGrasse Tyson?

  It was like a tone down.

• 2:19Harrison Greenbaum?

  Yeah, like this is a medium. Like, okay, we got it.

• 2:23Neil deGrasse Tyson?

  So let me, let me walk through what I'd like to explore and I want to hear how you would plug into it.

• 2:29Speaker 01

  All right, sounds good.

• 2:30Neil deGrasse Tyson?

  So we are all familiar with living in three dimensions. Okay, and we measure them all the time. We have height, width and depth. All right, and mathematically would just be X, Y, Z. That's how we do that, right? And we're good with that. We can move in any of these directions at any time. We have full fluidity in the spatial dimensions in which we occupy. Okay, now there's a fourth dimension we talk about, time. We are moving forward in time, but we don't have access to the past. So we are forever prisoners in the present, transitioning from our past to our future. So that's a different kind of coordinate. I don't want to worry about that just yet.

• 3:14Neil deGrasse Tyson?

  I just want to imagine that we have like a fourth spatial coordinate that you can move around in. That would just seems to me to be really cool. But before we get there, let's start small. Okay, so let's imagine a two dimensional being. That's something that only has height sort of and width, but not depth. All right, so this would be like the Edwin Abbott's book.

• 3:34Speaker 01

  Right.

• 3:35Neil deGrasse Tyson?

  Flatland.

• 3:35Speaker 01

  Flatland, right.

• 3:36Neil deGrasse Tyson?

  Flatland. Could you just remind us about the themes of that book, written like 100 years ago, right?

• 3:40Speaker 01

  Right, it's, he talks about what he calls Flatland, which is a two dimensional surface. He was a mathematician and circles and lines and polygons move around on this two dimensional space.

• 3:53Neil deGrasse Tyson?

  So polygon is just a, it's a, it's a, it's like a stop sign.

• 3:57Speaker 01

  Right.

• 3:58Neil deGrasse Tyson?

  It's an example of a square, a stop sign, this sort of thing.

• 4:00Speaker 01

  Yeah, what interesting thing about Flatland though is there's a lot of social commentary built into it. He, he criticizes Victorian values, especially with regard to, to women. Women are just lines and the way they, the way they communicate is by wiggling their back part. And it's very hierarchical.

• 4:19Neil deGrasse Tyson?

  I'd forgotten that.

• 4:20Speaker 01

  Very hierarchical, the polygons that have more sides are above, superior to triangles. For example, the ideal is a circle.

• 4:29Neil deGrasse Tyson?

  Yeah, even in two dimensional universes, people gotta divide themselves out. So there was a social hierarchy.

• 4:34Speaker 01

  Right, but then he imagined a third dimension. He's taken to the third dimension.

• 4:40Neil deGrasse Tyson?

  One of these creature characters in 2D.

• 4:43Speaker 01

  Yeah, he's a creature in 2D, but a third dimensional entity comes and takes him up and shows him what the third dimension looks like. And he goes back and he kind of proselytizes for the existence of this. We have this very parochial view of the universe. It's actually much greater, but the little beings don't, the two dimensional beings don't like that.

• 5:07Neil deGrasse Tyson?

  And they can't even.

• 5:08Speaker 01

  They're very parochial, yeah. They can't conceive of it, they get angry because they can't conceive of it and they think he's some sort of quack or whatever.

• 5:16Neil deGrasse Tyson?

  So instead of squares, you have cubes.

• 5:18Speaker 01

  Right.

• 5:19Neil deGrasse Tyson?

  Instead of triangles, you might have a pyramid.

• 5:20Speaker 01

  Right.

• 5:21Neil deGrasse Tyson?

  Three dimensional versions of those shapes.

• 5:22Speaker 01

  Right, yeah. And as the sphere comes down onto flatland, the circle, its intersection with the flatland gets bigger and bigger as the sphere descends or ascends.

• 5:33Neil deGrasse Tyson?

  So if you were a flatlander and you saw a point grow into a circle and the circle gets bigger and bigger, it gets to some maximum diameter and then shrinks back down and then disappears, that would be completely mysterious to you. But if you're a high, if you live in a higher dimension, in three dimensions, you would say, oh, that's just a sphere passing through your two dimensional universe.

• 5:54Speaker 01

  And it might be possible to infer the existence of the third dimension from that very process. Here's a circle gets bigger and bigger and then smaller and smaller.

• 6:03Neil deGrasse Tyson?

  They'd have to be able to imagine a circle, though. I mean, they'd have to imagine a sphere.

• 6:05Speaker 01

  Imagine a sphere, yeah.

• 6:06Harrison Greenbaum?

  Or some flatlander makes a ton of money as like their copper fields. Weird, look at this point, whoa. He has television specials.

• 6:14Neil deGrasse Tyson?

  So here's what's interesting to me, which gets kind of freaky fun. Okay, so when we as three dimensional space beings look at a two dimensional world, every creature.

• 6:28Neil deGrasse Tyson?

  Is completely transparent to us. We can see their entire innards.

• 6:34Speaker 01

  Right.

• 6:35Neil deGrasse Tyson?

  Whereas they cannot see their own innards. Because the boundary of those innards is the outer quote surface of what they see.

• 6:43Speaker 01

  And that's all they see, right.

• 6:44Neil deGrasse Tyson?

  And they just see that line.

• 6:45Speaker 01

  Right.

• 6:45Neil deGrasse Tyson?

  The textured line, but they can't see through that line unless they cut it open.

• 6:48Speaker 01

  Or they see a point if it's a polygon or a triangle coming towards them.

• 6:52Neil deGrasse Tyson?

  Okay, so that tells me that a four dimensional being looking at us would have access to every one of our interior organs and that would just be completely mysterious to us.

• 7:05Speaker 01

  Right, and the four dimension, I mean, you get into these standard puzzles, a four dimension. If there was a fourth dimension, even if you were locked in a cubicle jail, you could step into the fourth dimension and escape in the same way as you can escape from a circular enclosure by going into the third dimension and escaping.

• 7:22Neil deGrasse Tyson?

  So you can imprison an ant by drawing a box around it if an ant only really lived in two D's. You can imprison it, but we as three dimensional people just step over it.

• 7:31Speaker 01

  Yeah.

• 7:31Neil deGrasse Tyson?

  But to do so has to engage a third dimension for it to then come back down. And so, so it is out of their mental awareness.

• 7:41Speaker 01

  Right.

• 7:42Neil deGrasse Tyson?

  So, let me ask you. Are we not only prisoners of our timeline, are we prisoners of our three dimension? What, what will it take, you're the mathematician. You've calculated in higher dimensions before. What will it take to escape our three dimensionality?

• 7:57Speaker 01

  Well, I mean, three physical dimensions, that the threeness was probably established in the early moments of the universe after the first moments after the Big Bang.

• 8:09Neil deGrasse Tyson?

  Yeah, formation of the universe.

• 8:10Speaker 01

  Right, with the, the energy was sufficient to pop out a new dimension. But once it cooled a little bit, you, the third dimension was locked in at least. So people are using the second law of thermodynamics to. Explain the threeness of the dimension. And whether that's the case or not, there are lots of alternative theories, but that's one. And it's a little bit like a phase transition. You need energy to change phases from water to gas or whatever. And you need energy to bump up.

• 8:39Neil deGrasse Tyson?

  Or to melt ice to liquid.

• 8:41Speaker 01

  Right, to bump up a dimension and now it's cool.

• 8:44Neil deGrasse Tyson?

  I think about phase transitions all the time because it's a fancy term we use in physics, but it's for a very familiar thing. But it's so familiar that we no longer are astonished by it when we should be. Okay, here is this liquid. And then it becomes completely solid. Why aren't we freaking out every day about this?

• 9:04Speaker 01

  Yeah, no.

• 9:05Harrison Greenbaum?

  It happens when you take out your parents vodka and you replace it with water and then the thing explodes in the freezer.

• 9:09Neil deGrasse Tyson?

  Oh, you can't hide.

• 9:11Harrison Greenbaum?

  You're like, ah, you damn phase transition. Thwarted again.

• 9:14Neil deGrasse Tyson?

  Yeah, so you were replacing the vodka with water so they wouldn't know.

• 9:17Harrison Greenbaum?

  Right, but that expands and all of a sudden there's an exploding bottle.

• 9:20Neil deGrasse Tyson?

  You have such expertise at this.

• 9:22Harrison Greenbaum?

  Perhaps.

• 9:22Speaker 01

  Already put a Diet Coke can in the freezer and leave it there for a day and it comes out all.

• 9:27Neil deGrasse Tyson?

  Right, right, so it's a, well, that'd be, that's a different.

• 9:30Speaker 01

  That's a different, going in the other.

• 9:32Neil deGrasse Tyson?

  No, no, if you expand, that's a separate phenomenon.

• 9:34Speaker 01

  Yeah, right.

• 9:35Neil deGrasse Tyson?

  From just the phase transition. Yeah, so what you're saying is we missed a few phase transitions in the early universe. It could have been four dimensional, five dimensional beings.

• 9:42Speaker 01

  And these are defective dimensions if you believe in strength theory there.

• 9:47Neil deGrasse Tyson?

  But here's another interesting thing I learned. If you're a two dimensional creature, you cannot have a digestive tract.

• 9:54Speaker 01

  Or even a brain, actually. I mean, if you push it, I mean.

• 9:56Neil deGrasse Tyson?

  Well, no, a brain, not as we would know it, but you can imagine some network of lines. Some, but a digestive tract in us is a hole through a tube and has two ends to it, right? Okay, or three, but let's keep it a two for the moment. So you eat food, comes out the other side. It's a hole through us, but that tunnel is completely enclosed by our flesh. Okay, okay, so now this is your two dimensional being and has a mouth. And then it opens its mouth, you put food in. If that food goes through it and then comes out any place, that being is in two separate pieces.

• 10:38Harrison Greenbaum?

  Right.

• 10:38Speaker 01

  Unless the mouth closes and the anus, for lack of a better term, opens.

• 10:43Neil deGrasse Tyson?

  Oh. So.

• 10:47Harrison Greenbaum?

  This sounds like somebody who's also thought about Flatlander sex. Next question. How does it work?

• 10:52Speaker 01

  Yeah. What are we gonna do with all these?

• 10:54Neil deGrasse Tyson?

  Yeah, the top people we need working on this. So, so it would open its mouth, consume the food, close its mouth. That'll hold it, it's gotta like rea steel or something. That way it's still together as one thing comes and it's gotta open that. Okay, all right, okay, well, I got this now.

• 11:14Harrison Greenbaum?

  Unless you need to keep the food away from the rest of the body. Like, there's a reason it's being separated from the rest of us.

• 11:18Neil deGrasse Tyson?

  No, but no, it gets absorbed in.

• 11:20Speaker 01

  Yeah.

• 11:20Neil deGrasse Tyson?

  Through the walls.

• 11:21Speaker 01

  They need nourishment.

• 11:22Neil deGrasse Tyson?

  Yeah, yeah, that's where the nourishment comes from. Didn't you take Bio 101?

• 11:28Neil deGrasse Tyson?

  So, so it's these things that intrigue me. And that's why I brought you on, just to sort of wax.

• 11:36Speaker 01

  Wormholes is another topic that's very intriguing.

• 11:39Neil deGrasse Tyson?

  Yeah, yeah, I love wormholes. But you need, you know, we always show a wormhole as with one reduced dimension. Cause I guess we can't otherwise conceive of it.

• 11:48Speaker 01

  Right.

• 11:48Neil deGrasse Tyson?

  Right? We show a rubber sheet and there's like a punk, you know, a stretch that goes through it and it comes out the other side. But that rubber sheet is a, is our way of representing a full three dimensions.

• 12:00Speaker 01

  Right, it's just two.

• 12:01Neil deGrasse Tyson?

  Right, it's really, so we, so did you see the movie Interstellar?

• 12:06Harrison Greenbaum?

  Yes.

• 12:06Neil deGrasse Tyson?

  Okay, so they're coming upon.

• 12:09Harrison Greenbaum?

  I like the part with the Joker.

• 12:15Neil deGrasse Tyson?

  So they're coming upon a wormhole through space and it's just, it's a sphere. And you say, well, that's not a hole, but yes, it is. Because it's a hole in every direction. So you go in and you come out another side, but that requires a higher dimension for it to happen. And that's just, that's just cool. So what I, you know what I want? I want.

• 12:36Harrison Greenbaum?

  But in any dimension, is that movie fun to sit through?

• 12:42Neil deGrasse Tyson?

  Well, if you read the book, there was a tandem book, Matt, guess you didn't get the book. Oh, okay. The book is, it's an explanatory book, The Science of Interstellar. Ah. Written by one of the co-executive producers, who's a professor of theoretical physics at Caltech. Nice. Yeah, and it's like a coffee table book, but a lot of pictures and things from the movie, and he explains everything. That's awesome. Yeah, yeah, so you read that, and then you Then I'll get back to it. Then you reserve judgment, you call me in the morning. Yeah, I like the time stuff, the time stuff is great. Yeah, it's good, it's good, it's good. So, I just love thinking about dimensions, I also like thinking about a hypercube. A hypercube. Tesseract. Tell me about hypercubes.

• 13:21Speaker 01

  Hypercubes are just cubes of four and higher dimensions, yeah.

• 13:26Neil deGrasse Tyson?

  I like the math, too. He's still like Dazak. It's just, it's just a higher dimensional cube. Yeah, we have these, I got one in my pocket.

• 13:35Speaker 01

  Actually, if you look at the ordinary sense of dimension, which is some feature or aspect of a person or thing or whatever, you can have, you know, very high dimensional entities. I mean, if you allow, for example, look at a person, his height, his weight, his whatever, plus what he likes, the degree to which he likes it, the brands he likes, his, almost any dimension, you could have 50 dimensions, you look at eHarmony, 100 dimensions. What's interesting about that, if you think of a person as a 100 dimensional person, almost everybody on Earth is in the, on the edge of the hypercube. Because if you take a square, a 10 inch by 10 inch square, to use parochial units, and

• 14:18Speaker 01

  you stay a half an inch away from the edge, you know, only, what is it, nine times, 81% is in the interior and the rest is in the exterior. But now if you take a cube, and you take a look at the half inch around each one, Then it's nine times nine times nine. It's only about seventy-three percent in the interior.

• 14:36Neil deGrasse Tyson?

  The percent goes up.

• 14:37Speaker 01

  It goes, the percent goes down.

• 14:38Neil deGrasse Tyson?

  No, the percent of what is in, the percent of on the perimeter goes up.

• 14:42Speaker 01

  Right. And then you have four, it's sixty-two percent. If you have fifty dimensions, almost everybody is in the edge, around the edge.

• 14:49Neil deGrasse Tyson?

  Ooh.

• 14:50Speaker 01

  And it's, so in that sense, my father used to love this saying, he says, there's two kinds of, you've probably heard it, there's, there are two kinds of people in the world. The very strange ones and the ones you don't know so well.

• 15:00Neil deGrasse Tyson?

  Oh, okay.

• 15:00Speaker 01

  And so we're all really strange, because we're all in the periphery of this hypercube that describes us as a collection of, of dimensions, a collection of, uh.

• 15:10Neil deGrasse Tyson?

  Does that mean eHarmony works or not?

• 15:11Speaker 01

  Uh, I am not.

• 15:12Neil deGrasse Tyson?

  You're on the dating scene, what I, I know from your.

• 15:15Harrison Greenbaum?

  I am, I'm on all the apps. I'm on Tinder, I'm on J-Swipe, which is Jewish Tinder.

• 15:18Speaker 01

  Yeah.

• 15:19Harrison Greenbaum?

  It's like regular Tinder, but if you both swipe right, you get half of her father's business. It's great.

• 15:23Neil deGrasse Tyson?

  Right. So, I, I, so, uh, do you feel like your dimensionality is properly represented in your social profiles?

• 15:29Harrison Greenbaum?

  I think they should ask if you understand hypercubes, and that could, that could really get out. I use astrology. That's my big thing.

• 15:35Neil deGrasse Tyson?

  Oh, there, you go that.

• 15:36Harrison Greenbaum?

  I sit a girl down and I go, do you believe in horoscopes? And if she says yes, I end the date immediately.

• 15:40Neil deGrasse Tyson?

  Oh, I see. That's a filter.

• 15:42Harrison Greenbaum?

  Right. If she's like, what's your sign? I'm like, the exit. I'm out of it.

• 15:45Speaker 01

  It's worse than between you and I.

• 15:47Harrison Greenbaum?

  Yeah, exactly.

• 15:49Neil deGrasse Tyson?

  That's if you're, if you're hyper literate, you'll, uh, back when Cosmos was airing, there, there was a comic that was really cute. There was a speed dating, right? And, uh, one person says to the other, uh, uh, have you seen Cosmos? And the person says, what's Cosmos? And the person says, next. Yeah. I said, whoa, that's good. That's like putting some academic pressure, you know, on your speed date encounter.

• 16:11Harrison Greenbaum?

  Absolutely.

• 16:12Neil deGrasse Tyson?

  So, so let's continue the hypercube. So, uh, so what, so describe to me how you get there. Because I, when I think of it, I think of, I'll start with a line, and the line is one dimension, because it only has length. And it's bounded by two.

• 16:25Speaker 01

  Points.

• 16:25Neil deGrasse Tyson?

  Points, each with zero dimension. Points doesn't have like height, width, or depth or anything. Okay? That's kind of interesting to me.

• 16:32Harrison Greenbaum?

  But I only see a cube if you hand it to me.

• 16:34Neil deGrasse Tyson?

  But wait, so watch. Oh, no, no, no, watch, watch. So now I take this line, and then I sort of. Rotate it out into an axis, then I get a square. So a square has two dimensions to it, but it's bounded by four one-dimensional lines. That's just kind of interesting. So now I take that square and slide it up to get a cube out of it. So now a cube has six sides, each bounded by two-dimensional surfaces.

• 17:05Speaker 01

  It's called a dy.

• 17:07Neil deGrasse Tyson?

  A what?

• 17:08Speaker 01

  A dy.

• 17:09Neil deGrasse Tyson?

  Oh, a dy, yes.

• 17:10Speaker 01

  Okay, sorry.

• 17:11Neil deGrasse Tyson?

  Excuse me. Okay, so now if I want a four-dimensional cube, I take this three-dimensional cube and pass it into a fourth dimension, and thereby I end up with eight sides, each a cube. The side is itself a cube, and we just can't think of that. But you're a mathematician, you've been doing... Can you think, can you think in four dimensions? Or is it still weird for you?

• 17:36Speaker 01

  No, you still have to resort to cross-sections. I mean, there's, there are animated versions of the tesseract, where it rotates...

• 17:44Neil deGrasse Tyson?

  The tesseract is the four-dimensional cube.

• 17:45Speaker 01

  It's the four-dimensional cube, where it rotates and you look at the various cross-sections. You can get a little bit of a, of a feel, but, uh, no, I mean, some people, I mean, Thurston, a late mathematician at, I think he was at Princeton, uh, did have a kind of visceral feel for four-dimensional, uh, entities, but, uh, most people, most mathematicians...

• 18:07Neil deGrasse Tyson?

  Okay, so I don't feel so bad?

• 18:08Speaker 01

  No, you don't have...

• 18:09Neil deGrasse Tyson?

  Okay. Gotta take a quick break. When we come back, we will be joined by a good friend and fellow physicist, James Cocalio. Some of you know him as the world's expert on the physics of superheroes. There's some higher dimensionality going on there. We will bring him into the conversation as well as queries from our families.

• 18:40Neil deGrasse Tyson?

  We're back at Mashable Headquarters in New York City for StarTalk. Topic of today is higher dimensions. And I got help, I got mathematician right here, John Paulos. And coming in on video call, John Kakalios. How you doing, man?

• 18:57Speaker 03

  I'm doing great. How are you?

• 18:59Neil deGrasse Tyson?

  Excellent, excellent. You've met my co-host for today, Harrison Greenbaum. And, and wait, wait, for those of you who see this on video, you have superheroes dangling from your wall. Now, I know you wrote the book, The Physics of Superheroes, but they appeared, little versions of them have appeared to invaded your, your, your den.

• 19:18Speaker 03

  You may think of them as action figures, Neil, but to me, they are lecture demonstration tools.

• 19:25Neil deGrasse Tyson?

  Oh, that's how you, that's how you explain that to your mother and to your wife? Yes, okay.

• 19:32Speaker 03

  And my department chair, yes.

• 19:35Harrison Greenbaum?

  You've been expensing a lot of action figures.

• 19:39Speaker 03

  Moving on.

• 19:43Neil deGrasse Tyson?

  One of your favorite books of mine is The Physics of Superheroes, but that's not your latest book. Remind me of your latest book?

• 19:48Speaker 03

  The latest book is, oh, and hair. I happen to have it right here. Who says this isn't the Marvel age of shameless plugs? The Physics of Everyday Things.

• 19:58Neil deGrasse Tyson?

  Excellent, excellent. So you're, you're, you're the, you're everyone's sort of man about town physicist.

• 20:04Speaker 03

  It, it, there are, there are people who cover astrophysics. There are people who do the Higgs boson. I cover all the nitty gritty stuff that surrounds us every day. And explain how physics is useful not just to explain colliding neutron stars, but also to explain our Fitbit.

• 20:24Neil deGrasse Tyson?

  Okay. Very good to know.

• 20:27Harrison Greenbaum?

  I got rid of my Fitbit.

• 20:28Neil deGrasse Tyson?

  You got rid of it.

• 20:29Harrison Greenbaum?

  It measures your motion based on wrist activity. And I was like, I don't need people to know I run a marathon at 4 a.m. every evening.

• 20:35Neil deGrasse Tyson?

  So what we've got here, we're in the Cosmic Queries

• 20:38Harrison Greenbaum?

  Yes.

• 20:39Neil deGrasse Tyson?

  Section of our Star Talk. And Harrison, you've collected questions.

• 20:45Harrison Greenbaum?

  All the questions.

• 20:47Neil deGrasse Tyson?

  Bring it on.

• 20:48Harrison Greenbaum?

  All right.

• 20:48Neil deGrasse Tyson?

  Bring it on. I've got two experts here. I could just like go to the Bahamas right now because we've got all the expertise you need for higher dimensions. And so much of people's access to higher dimensions and knowledge of higher dimensions comes from superhero movies. So let's see what you've got.

• 21:01Harrison Greenbaum?

  Yeah. So the first question comes from our Patreon. So thank you for

• 21:04Neil deGrasse Tyson?

  Patreons, okay.

• 21:05Harrison Greenbaum?

  For supporting us. And this one is from Orlando, Florida. So he's near a superhero theme park. We've seen compelling theories that postulate everything from four to 26 dimensions in our physical world. What's so special about the fourth dimension? Is there anything mathematically unique about it compared to what we consider spatial dimensions? I think we pretty much answered that, but.

• 21:23Neil deGrasse Tyson?

  Ooh. Yeah.

• 21:25Harrison Greenbaum?

  Is there anything mathematically unique about it?

• 21:27Speaker 01

  It's physically, I mean, there are arguments for it. As I said, the second law of thermodynamics suggests that once the early universe cooled a bit, it didn't have enough energy to

• 21:40Neil deGrasse Tyson?

  To birth out another dimension.

• 21:41Speaker 01

  To birth out another dimension if you wanted the second law to hold. So the fourth is beyond us.

• 21:48Neil deGrasse Tyson?

  You're saying we're stuck with four dimensions?

• 21:49Speaker 01

  We're stuck with three and one. Yeah, four dimensions. So I mean, there are these other deficient, for lack of a better term, dimensions, if you believe in string theory. But, you know.

• 22:02Neil deGrasse Tyson?

  Okay.

• 22:04Speaker 01

  I mean, there are lots of theories. I mean, Kant had his own theory, but I don't want to get into Kant.

• 22:10Neil deGrasse Tyson?

  Immanuel Kant?

• 22:11Speaker 01

  Immanuel Kant.

• 22:12Neil deGrasse Tyson?

  Okay, yeah. But he didn't know anything about cosmology.

• 22:15Speaker 01

  No. Well, one thing he did, he made a distinction that many people derided between numina and phenomena. Numina is the way things are that we'll never know. Phenomena is the way we see things. We are a priori categories. And in a way, I mean, the string theory is something we'll never know. And the extra dimensions and other universes, we'll just never know.

• 22:36Neil deGrasse Tyson?

  In physics, we don't give a rat's ass about what something is if what it is is not revealed to us through a measurement.

• 22:42Speaker 01

  Yeah, but.

• 22:44Neil deGrasse Tyson?

  Would you agree with that?

• 22:45Speaker 03

  I would. It is kind of disturbing that of all the extra dimensions, none of them are in the time domain. They all seem to be extra spatial dimensions, because if they were in the time domain, then maybe we could move back and forth in time the way we move back and forth in space. And in fact, science fiction stories have sometimes suggested that that would be how time travel would occur.

• 23:10Neil deGrasse Tyson?

  So, help me on this. So if we had more than one time dimension accessible to us, does that mean we can just go off in one time coordinate while freezing our movement in the other time coordinate and do things with our life and then return and then continue? Because that's what I do spatially.

• 23:27Speaker 03

  Why not? I... presumably that would be in fact the case.

• 23:34Neil deGrasse Tyson?

  That's kind of cool.

• 23:35Speaker 03

  Yeah. So that... I can't remember where. It might have been even an H.G. Wells short story about that might be a way of achieving time travel, that they discovered that there's other pathways, just so you can get from one point to another, taking alternate routes.

• 23:54Neil deGrasse Tyson?

  Alternate time routes.

• 23:55Speaker 03

  You could... It's spatial routes. We do it all the time.

• 23:58Neil deGrasse Tyson?

  Right, right.

• 23:59Speaker 03

  So...

• 24:00Neil deGrasse Tyson?

  Oh, I see. You'll take a shortcut. You'll do it all. You'll go backwards to where you once were.

• 24:06Speaker 03

  Exactly.

• 24:07Neil deGrasse Tyson?

  You'll get your old haunts. Yeah.

• 24:08Speaker 03

  It's like a time shortcut. Yeah. So you could have a time shortcut, right. That would be interesting. But they never want to add another time dimension when they need to add dimensions.

• 24:20Neil deGrasse Tyson?

  But is this anything different from the wiggly, wobbly, timey-wimey time of Doctor Who?

• 24:28Speaker 03

  I think that ultimately, the reason why there are only extra spatial dimensions isn't in fact just that, to avoid saying, well, they kind of postulate, time travel's not going to happen, so everything has to stay, all the extra dimensions are spatial.

• 24:43Speaker 01

  Well, time travel always leads to the grandfather paradox. You go back in time and you're your grandfather. And that's the universe splits there. One universe, your grandfather...

• 24:54Speaker 03

  That's the many worlds. So that's the many worlds. That's right. So you can go back in time, but it's an alternate, so you can kill as many grandfathers as you got bullets.

• 25:02Harrison Greenbaum?

  Would Trump be president? There's nobody who's using their time travel to come back and be like, "What are you doing?" I'm work, I'm working on it. I'm working on it.

• 25:10Neil deGrasse Tyson?

  All you have to do is prevent your grandfather from meeting your grandmother.

• 25:13Speaker 01

  Yeah.

• 25:13Neil deGrasse Tyson?

  Then you won't be born. Or delay when they had sex by 10 minutes.

• 25:18Harrison Greenbaum?

  This guy with blood on his hands, he's like, you just had to go to the library.

• 25:24Harrison Greenbaum?

  Oh, my God.

• 25:26Neil deGrasse Tyson?

  Let's go to the next question.

• 25:27Harrison Greenbaum?

  All right. Uh, this gets us to our next one from Justin Colado in Facebook. How much cannabis do I have to smoke to get to the fourth dimension?

• 25:34Neil deGrasse Tyson?

  Oh.

• 25:36Harrison Greenbaum?

  I'm assuming he's in Seattle.

• 25:39Neil deGrasse Tyson?

  Or Colorado.

• 25:40Harrison Greenbaum?

  Or Colorado.

• 25:41Neil deGrasse Tyson?

  We got good places for that.

• 25:44Harrison Greenbaum?

  What are you looking at me for?

• 25:47Neil deGrasse Tyson?

  Okay, so John, when you get deep into your math, how much cannabis does is required to reach different dimensionalities in your analysis?

• 25:56Speaker 01

  Uh, I don't know.

• 25:58Neil deGrasse Tyson?

  Don't know. Okay. Okay, so that's an experiment that you could perform.

• 26:03Speaker 01

  Yeah, well, in my particular case, it'd probably be a tiny amount since I don't ever engage in such. So I think a tiny little bit and I'd be in the fifth dimension.

• 26:15Harrison Greenbaum?

  Time slows down when I use it. So that's a way of changing the fourth dimension.

• 26:19Neil deGrasse Tyson?

  Right. So it's not for you?

• 26:20Harrison Greenbaum?

  For me.

• 26:21Neil deGrasse Tyson?

  Yeah, yeah, yeah. Rest of us are looking.

• 26:22Harrison Greenbaum?

  My friend.

• 26:24Neil deGrasse Tyson?

  Oh, your friend?

• 26:24Harrison Greenbaum?

  Yeah. My friend in Colorado.

• 26:26Neil deGrasse Tyson?

  Who smokes?

• 26:27Harrison Greenbaum?

  I don't know anything about that.

• 26:30Neil deGrasse Tyson?

  All right, next one.

• 26:31Harrison Greenbaum?

  All right, cool. Uh, this is from the StarTalk website. Is there a study of physics that delves into the zero D dimension? Every other dimension possibility is looked at like in string theory, but why is the possibility of dimensions lower than one excluded from that line of thought?

• 26:43Neil deGrasse Tyson?

  Well, technically they're not because that's what a singularity is in the center of a black hole. That's what the singularity was at the birth of the universe. That's the definition of a singularity. So now here's the problem. And, and, and James, correct me if I'm wrong here, or if you think differently about it, the, what's interesting about these singularities is that we know in advance that's where Einstein's general theory of relativity breaks down. We need a new way to gain access to what's going on in the universe at those points of singularity. And it's been said that's where God is dividing by zero. We're like, you're not supposed to do that. Okay. So, so, and string theorists are supposed to be lining up to handle that limit, that limiting case.

• 27:28Neil deGrasse Tyson?

  So, so, yes, that, that, this writer needs to think of singularities as the zeroth dimension. And James, what, could you add to that?

• 27:34Speaker 03

  I, I would, I, so, along what you just suggested, Neil, the tricky part is that if you're going to base, you say physics only cares about things that you can measure, and what the evidence is, and at the singularity, we have no evidence, and all of our equations break down, it makes it rather tricky to then have a theory that accounts for the singularity, and then presumably would then account for things that we're observing today, um, to try to justify.

• 28:06Neil deGrasse Tyson?

  I hadn't thought about that. What you're saying is, you can't use a macroscopic object to measure a zero-dimensional thing.

• 28:12Speaker 03

  Right. So, or, or going back to that, to that point, you know, of the singularity, it's like, where's the evid, you know, we say, what's the evidence, or what's the, what's the data?

• 28:23Neil deGrasse Tyson?

  You have to be there, but you can't be there if everything is singular. Uh, all right, next question.

• 28:28Harrison Greenbaum?

  All right. Uh, so, this is sort of related, we touched on it a little bit, but this guy on the website, Gary F. Anderson, he said, supposedly before the Big Bang, dimensions didn't exist. When the Big Bang manifested itself, dimensionality suddenly came into existence. Did that dimensionality expand at the speed of light? Or did it just instantly pop into existence, creating an infinite, empty universe?

• 28:47Neil deGrasse Tyson?

  Well, everything we know says that we were endowed by the matter, energy, space, and dimensionality from the, the, the transition from an extremely high-temperature universe to one that's much cooler, and we're freezing out these properties as the universe expands and cools. So, so, it, so, so, James, would, would you add or subtract anything from that account?

• 29:12Speaker 03

  Not at all. I'm a humble but lovable, solid-state experimentalist, so.

• 29:17Neil deGrasse Tyson?

  No, don't blame me for this Big Bang stuff.

• 29:20Speaker 03

  No, no, but this is not my area of expertise, so I will defer.

• 29:25Neil deGrasse Tyson?

  Yeah, so, I mean, we, it's, you get this at different stages of the extremely early universe, and so, uh, we're stuck with the universe we have. Get over it. Next one.

• 29:36Harrison Greenbaum?

  That's fair.

• 29:36Neil deGrasse Tyson?

  Got time for one more before we take a break.

• 29:38Harrison Greenbaum?

  Yeah. Green Meteor from Instagram said, is death the fourth dimension?

• 29:43Neil deGrasse Tyson?

  Ooh.

• 29:44Speaker 01

  Sounds, seemed like more the zeros dimension.

• 29:49Speaker 01

  Just disappear.

• 29:52Neil deGrasse Tyson?

  Yeah, I would agree. Death is the zeros dimension.

• 29:54Speaker 03

  Yeah. I'm going with that.

• 29:57Neil deGrasse Tyson?

  You're going with that. We got three.

• 29:58Speaker 03

  It works for me.

• 29:59Neil deGrasse Tyson?

  We're three and O here. We're going with it. Okay, we got another one.

• 30:02Harrison Greenbaum?

  Sure. Richard Adams on Facebook says, do accounts of powerful deities make more sense when you consider higher dimensions?

• 30:09Neil deGrasse Tyson?

  Ooh.

• 30:10Speaker 03

  Well, you know, when you think about like the, the, the flat land example, that if we lived in a flat dimension, a three dimensional, uh, a person who could put things in and out of our flat dimension would seem, you know, extra physical, you know, would seem, uh, beyond our realm or our understanding.

• 30:30Neil deGrasse Tyson?

  And is that what Thor is to Earth? Thor exists in higher dimensions. They have access to space time dimensions that we don't? Isn't that correct?

• 30:39Speaker 03

  Presumably.

• 30:41Neil deGrasse Tyson?

  Well, you're my comic book guy. Don't tell me presumably.

• 30:44Speaker 03

  But, but well, they, they've gone back and forth on that of saying, oh, it's magic. Or saying that there's a scientific, it's just like hyper-science or back to it's magic. So, um.

• 30:57Neil deGrasse Tyson?

  But I think the takeaway here is that it's clear that if you live in a higher dimension, relative to some community of beings, you are all powerful and all knowing in ways they will never understand or imagine.

• 31:11Speaker 03

  Yeah, I think that's, I think that's right. I think that's right.

• 31:15Neil deGrasse Tyson?

  Yeah, I think the answer is basically yes.

• 31:18Speaker 03

  Yeah.

• 31:18Neil deGrasse Tyson?

  Yeah, it's indistinguishable from what a high, and deeply religious people will say God is, is a, is, knows all and, and is all powerful. They, they will describe powers, describe powers to God that.

• 31:33Neil deGrasse Tyson?

  Any of us would give to a four to a higher dimensional being. If they, yeah, I think that would be a trivial.

• 31:39Speaker 01

  And we could have a hierarchy of gods too, the fourth dimension, the fifth dimension, sixth dimension.

• 31:43Neil deGrasse Tyson?

  Yeah, yeah.

• 31:44Harrison Greenbaum?

  So I just need to find a flatland and be God.

• 31:46Neil deGrasse Tyson?

  That's what you, is that your first thought? Is that, is that what you?

• 31:51Harrison Greenbaum?

  Yes, the cult of Harrison, there'll be a bunch of flatlanders giving me two dimensional offerings.

• 31:57Speaker 03

  Like the tiny insects you are.

• 32:02Neil deGrasse Tyson?

  Well, when we come back, more cosmic queries on higher dimensions. When StarTalk returns.

• 32:14Neil deGrasse Tyson?

  We're back on StarTalk, Cosmic Queries segments. We're talking about higher dimensions beyond the three spatial and one time dimension with which we are familiar. I've got math professor John Paulos, I got my co-host.

• 32:29Harrison Greenbaum?

  Yeah.

• 32:29Neil deGrasse Tyson?

  Harrison Greenbaum, and on video call, I've got James Kakalios. One of my favorite people out there of them all, Mr. Superhero Expert. So we got questions from our fanbase.

• 32:41Harrison Greenbaum?

  Yeah.

• 32:41Neil deGrasse Tyson?

  So, so what do you have?

• 32:43Harrison Greenbaum?

  Alex Lanter from Twitter wrote, is a tesseract a fourth dimensional object? Follow up, what is a tesseract? So that's weird that this person doesn't even know what it is, but he's asking about that.

• 32:52Neil deGrasse Tyson?

  Cause he's seen it in the movies.

• 32:54Harrison Greenbaum?

  Yeah.

• 32:54Neil deGrasse Tyson?

  So, so, so obviously the word tesseract has its origins in mathematics. And it was then co-opted by the Marvel Universe, I presume. So what, earlier in our first segment, we talked about the tesseract just as a four dimensional cube. So if you can tell us, what role does it play in the Avengers Pantheon?

• 33:16Speaker 03

  Not so much the Avengers, the Fantastic Four at one point had their headquarters. That was kind of a tesseract so that they could be on just a warehouse, um, on the, uh, New York, uh, wharf. And yet have managed to have the, uh, facilities of a skyscraper there.

• 33:34Harrison Greenbaum?

  It was a real estate device?

• 33:35Speaker 03

  Exactly. It was a real estate, it was a real estate scam. It's bigger on the inside, trust me.

• 33:42Neil deGrasse Tyson?

  Bigger on the inside, like Doctor Who's, um, uh, police call box, the TARDIS, like Mary Poppins' bag. Where she puts mirrors and lamps out of it, like Hermione's purse in Harry Potter.

• 33:58Harrison Greenbaum?

  The wardrobe from Lion and the Witch and the Wardrobe? Or is that really more of a portal?

• 34:02Neil deGrasse Tyson?

  No, it was more a portal. I thought of that more as a portal rather than a container. Uh, inside. What's the movie I'm remembering where the, like, the tesseract was in this, in a NASA facility?

• 34:12Speaker 03

  Oh, oh, they were talking about, so that was, um, the tesseract was actually one of the infinity stones. That was in the first Avengers film. I know it. Yes, yes. And so that's that blue glowing, um, uh, stone. And that was supposed, that has been later identified as the space infinity gem or infinity stone. That gives you ultimate control over space. So it, it was viewed naively as a tesseract. Just basically as a portal or some way to go from one point to another. And now it's recognized that it would give you control over any point in space.

• 34:53Neil deGrasse Tyson?

  So when you say now it is recognized, was there some team of researchers that, a crack team of, like, what do you mean? Now it came to be realized?

• 35:01Speaker 03

  Yes. When Thor went into that little mystic pool in Avengers 2: Age of Ultron. He recognized that what, what they were dealing with were the infinity stones. Um, we saw a purple power infinity stone in Guardians of the Galaxy. Um, the vision has a yellow, uh, mind stone that gives you powers.

• 35:24Neil deGrasse Tyson?

  Okay, so tesseract was just a holding, a holding word.

• 35:27Speaker 03

  It was basically, it was a holding word.

• 35:29Neil deGrasse Tyson?

  They needed a cool word until they could figure out how to do more with this thing.

• 35:34Speaker 03

  Right.

• 35:34Neil deGrasse Tyson?

  Okay. And now there's a Trump tesseract tower.

• 35:40Neil deGrasse Tyson?

  The Trump tesseract. That, that'd be a, that, that's a, okay, so that'd be a building you walk into and it's way bigger on the inside. Then it would be on the outside.

• 35:48Harrison Greenbaum?

  And that's, isn't there a cosmic cube?

• 35:50Neil deGrasse Tyson?

  There's a joke in there somewhere. Come on.

• 35:51Harrison Greenbaum?

  There's so many. I'm gonna use my tesseract to go back in time and, uh, but there, I, cause I was getting, I was nerding out. Cause isn't there also the cosmic cube, which is like?

• 36:01Speaker 03

  That, okay, so they were referring to the tesseract a little bit as the cosmic cube in Captain America: First Avenger. And then in the Avengers movie, in the comic books, the cosmic cube is a cube that when you're holding it, you can change reality. So in some sense, it was like the reality stone, infinity gem. In that you could just change, so suddenly if the red skull. Was holding the cosmic cube, he could, we could suddenly be in a world where Germany won World War II.

• 36:30Neil deGrasse Tyson?

  So a different, a different outcome of events in the world.

• 36:33Speaker 03

  Whole different realities, or everyone has like, you know, a third eye or forearm. You could, you could change any aspect.

• 36:41Neil deGrasse Tyson?

  And that was primarily, that was primarily through the comics rather than through the films.

• 36:45Speaker 03

  Yes, except that in Thor, the dark world, God, it is so sad I know all this. Uh, the red.

• 36:53Neil deGrasse Tyson?

  We weep for you.

• 36:55Speaker 03

  With ether.

• 36:56Harrison Greenbaum?

  I'm on the same boat. I lost my virginity in college, so we're fine.

• 37:01Speaker 03

  The ether that Thor and the dark elf Malekith fought over turned out to be identified to be the reality stone. So that is introduced into the Marvel Cinematic Universe and will be seen that presumably in Avengers three and four.

• 37:17Neil deGrasse Tyson?

  So these are other space, space paths, not time paths.

• 37:22Speaker 03

  Right.

• 37:23Neil deGrasse Tyson?

  So other realities that.

• 37:24Speaker 03

  There is a time stone. We haven't seen that one yet though.

• 37:28Neil deGrasse Tyson?

  Okay, alright. So next one.

• 37:29Harrison Greenbaum?

  Nice.

• 37:30Speaker 03

  Sorry, we have seen it. We saw it in Doctor Strange. Doctor Strange in the Eye of Agamotto had the time stone. That's why he was able to trap Dormammu in the time loop. Oh, spoiler alert.

• 37:41Harrison Greenbaum?

  Alright, this next question comes from Nanuk Shakook.

• 37:46Neil deGrasse Tyson?

  Let it be.

• 37:48Harrison Greenbaum?

  It rhymes, alright. Could it be plausible that the edge of the universe is merely the end of a dimension and possibly the start of another? Dot, dot, dot, just a thought.

• 37:57Neil deGrasse Tyson?

  Well, so it turns out variations on the multiverse idea have it that there are pockets of the universe that are expanding in such a way that other expanding zones don't know about each other. Okay, so the independently expanding zones within sort of the space that's spread out among this metaverse, if you will, this multiverse. And so, the edge of your universe is technically the edge of your reality, but I learned this, uh, James, I don't know if you knew this, I learned this like a week ago from a cosmology colleague of mine, that you can have one edge of an expanding universe bump into the edge

• 38:42Neil deGrasse Tyson?

  of another expanding universe, and that would show up as a circle, because these are expanding bubbles, which with two bubbles intersect, you get a circle, and that would show up in sort of the cosmic microwave background.

• 38:54Speaker 01

  Flatland, the sphere coming down.

• 38:55Neil deGrasse Tyson?

  The sphere coming through. So, so, uh, so I don't, I don't think we can think of it so much as another dimension, but it certainly would be the boundary between your universe and other universes. And so, uh, so that, that's gotta be pretty good, if you found a way to portal from one to, to tunnel from one to the other. You do a lot of tunneling in your, in your microphysics, don't you?

• 39:21Speaker 03

  Yeah, I, actually, we do. All I know is that if one universe bumps into another universe, your insurance rates are going up.

• 39:29Neil deGrasse Tyson?

  Okay. No, you get one forgiven collision.

• 39:33Speaker 03

  Oh, you get one, that's, that's.

• 39:34Harrison Greenbaum?

  Yeah, it's no fault.

• 39:35Speaker 03

  One freebie, the mulligan, yes.

• 39:37Neil deGrasse Tyson?

  All right, Harrison, what else you got?

• 39:39Harrison Greenbaum?

  All right, uh, since the Higgs field, this is from Gavin Minton on Facebook, since the Higgs field creates mass, and massless particles do not experience time, does that mean that the Higgs field creates time? Is time simply a bizarre emergent property of the Higgs boson?

• 39:53Neil deGrasse Tyson?

  I love it. I don't know if it's true, but I love the idea. What, what do you think, James?

• 39:58Speaker 03

  Yeah, that's, that sounds great.

• 39:59Neil deGrasse Tyson?

  Right, because without the Higgs boson, uh, you would have no particle mass, and only particles with mass experience time. The question is, can you experience time if there's no mass and no speed of light particles? Can you even imagine time? Or maybe time has no meaning, because there is no sequence of events for you to measure. What do you think?

• 40:23Speaker 03

  Right, I think that's, I think that's exactly right, what you just said there, that if there's, if there, time is the thing that we use to kind of order, uh, you know, what comes first, what comes second, and if, if they're occurring all simultaneously, then, uh...

• 40:39Neil deGrasse Tyson?

  It's all simultaneous, or nothing is happening anywhere.

• 40:41Speaker 03

  Right, right.

• 40:42Neil deGrasse Tyson?

  Then time has no meaning.

• 40:45Speaker 03

  The thing is that different particles interact with the Higgs field, they couple in different ways, which is why they have different mass. Um, and yet, no matter how they couple to the Higgs field, they all seem to experience time the same way.

• 40:59Neil deGrasse Tyson?

  That's an interesting point. So even the high mass particles experience time at the same rate that a low mass particle does, but different unstable particles decay at different rates than do other unstable particles. So that's one of the great mysteries that you get. This particle decay in 30 seconds, this one in six minutes, reliably, predictably every single time.

• 41:25Speaker 01

  Well, one thing that strikes me is that often in these speculations, the interplay between the English language and physics is very nebulous. I mean, even, I mean, Pon Kray once said that you could, the mathematician and physicist, that you could insist that the universe was Euclidean. If you, and if you did, you'd have to introduce fictitious forces and strange torques and accelerations. So you, you pick your, your physics geometry combination, and you can make it whatever you want to some extent. He had this conventional view of philosophy of math. But if you do pick it one way, you've got to change the physics. And so.

• 42:05Neil deGrasse Tyson?

  So this is, this reminds me of the quote, was it attributed to Einstein, where it's time is invented to make motion look simple.

• 42:14Speaker 01

  Yeah, that, that's a.

• 42:16Neil deGrasse Tyson?

  What do you think of that?

• 42:17Speaker 01

  A conventional theory of time.

• 42:19Harrison Greenbaum?

  Like when I, as a comic, you light a comic to say you have two minutes left. So I always joke, can we light people based on how long their set has felt?

• 42:26Neil deGrasse Tyson?

  That's good.

• 42:28Harrison Greenbaum?

  Yeah. Cause he's been on stage for an hour, according to my perception.

• 42:32Speaker 03

  It's the relativistic theory of standup, yes.

• 42:35Neil deGrasse Tyson?

  The time dilation of comedic capacity to entertain.

• 42:39Harrison Greenbaum?

  Speaking of time going slower than it should, let's talk about the movie Interstellar. How do you feel about the accuracy of the presentation of the fifth dimension in the movie Interstellar? That's from LookaYoYo89 on Instagram.

• 42:53Neil deGrasse Tyson?

  Yeah, I have issues with the interior of the black hole in the library and he sees, I like their, that their attempt to portray that, where the sort of infinite. Uh, uh, boulevards, basically, of space. I'd like the attempt, and so, and I can't come up with a better attempt. So who am I to judge it? But if I were to, if you asked me, I would say that's probably not what it's actually like. But I don't know how else to say why that's so. James, what do you think?

• 43:22Speaker 03

  And actually, didn't he, existing in a higher, a five dimensional space, he was able to move around then in time? Because he was able to then go to, to like his, when his daughter was young or some later time. And so it was the same notion that he was in the, what we've been talking about before, about Flatland. He was actually able to move around in a higher dimension.

• 43:46Neil deGrasse Tyson?

  And I just don't know how he could do sort of Morse code with book titles, but from the backside of each book. How well do you know your books that the other side of the book, you can identify the title?

• 44:01Harrison Greenbaum?

  Right, because he's on the other side of the shelf.

• 44:02Neil deGrasse Tyson?

  He's on the other side of the shelf, poking, poking them through.

• 44:05Speaker 03

  Oh, yeah.

• 44:06Neil deGrasse Tyson?

  I have issues.

• 44:07Harrison Greenbaum?

  He can travel through five dimensions, but he can't go to the other side of the bookshelf.

• 44:11Neil deGrasse Tyson?

  Just turn around. Yeah, just turn the brick around, right?

• 44:16Neil deGrasse Tyson?

  We've got time for like one or two more questions. All right, go.

• 44:18Harrison Greenbaum?

  All right.

• 44:19Neil deGrasse Tyson?

  Those will be soundbite mode, okay? All answers in soundbites, go.

• 44:22Harrison Greenbaum?

  Cool, this one's good. This is from Tony from El Paso, Texas. Is it possible to fabricate an artificial dimension? And if so, could we theoretically create an artificial dimension and send people there to solve our overpopulation?

• 44:33Neil deGrasse Tyson?

  I'm not authorized to respond to that from my knowledge of national security. Uh, that would be cool, James, if you can manufacture a dimension.

• 44:41Speaker 03

  I, I could go into this, but it involves proprietary technology right now.

• 44:45Neil deGrasse Tyson?

  That's right. So both James and I are, are silent on this.

• 44:49Harrison Greenbaum?

  I think it's the Trump tesseract. I think, I think we've already spilled the beans.

• 44:54Neil deGrasse Tyson?

  No, it would be, it would be really cool if you, if you could do that.

• 44:57Speaker 01

  Well, I mean, wormholes, I mean, you, something like that. I mean, wormholes strike me as sort of like entangled particles writ large.

• 45:05Neil deGrasse Tyson?

  What I want is a box in my, on my desk where, because I already stack, the surface is already covered and I already got stuff stacked. But now I need something to put it in a fourth dimension.

• 45:14Harrison Greenbaum?

  Oh, see, I, I can have, yeah.

• 45:16Neil deGrasse Tyson?

  The stacked pages must look really mysterious to ants on the surface of the desk. Because the pages just disappeared. But they actually were elevated into a third dimension. And you could store way more papers up in a third dimension than you ever could two dimensionally on the surface of the desk. So I'm thinking now if I have boxes, I'll just need a four dimensional portal and put all the boxes in the four dimensional portal. I could do that like forever. Am I, am I, am I right there, James?

• 45:42Speaker 03

  I think it will not violate any point of entropy because no information will be preserved.

• 45:49Neil deGrasse Tyson?

  No, I'm not saying put it forever, you can access it later if you want.

• 45:53Speaker 03

  I'm just talking about the stacks that I have right now.

• 45:57Harrison Greenbaum?

  If I had any physical object, I would have like a Schrödinger's cat. I would have a cat that's dead and alive simultaneously.

• 46:02Neil deGrasse Tyson?

  That's creepy.

• 46:03Harrison Greenbaum?

  It'd be, it'd be awesome for Halloween.

• 46:05Neil deGrasse Tyson?

  Yes, it would be awesome.

• 46:06Speaker 03

  Are you trying to get out of feeding it or changing the litter box?

• 46:09Harrison Greenbaum?

  Right, you wouldn't have to because at that point it's dead, but then it's not.

• 46:13Neil deGrasse Tyson?

  All right, well, so rather than take care of it, he said, I will now have dead cat.

• 46:17Harrison Greenbaum?

  Right.

• 46:17Neil deGrasse Tyson?

  For the day, so I don't have to.

• 46:18Speaker 01

  I think it's no accident that dimensions sound like dementia.

• 46:26Neil deGrasse Tyson?

  Let's do one more question.

• 46:27Harrison Greenbaum?

  All right.

• 46:27Neil deGrasse Tyson?

  The last one.

• 46:28Harrison Greenbaum?

  This is one is from Call Him Bob, and his name is Bob, so call him Bob. Uh, is there an upper limit to the possible number of dimensions? And if so, how do we know and why does it exist?

• 46:39Speaker 01

  Well, physical dimensions, I mean, the dimensions in the everyday sense, there's no limit. You could go eHarmony, there's a hundred dimensions. But physical dimensions, it's not clear. I mean, 26 people used to talk about, but I don't know if there's any physical limit.

• 46:53Neil deGrasse Tyson?

  Yeah, I don't know either. Do you know, James?

• 46:56Speaker 03

  No, I don't think, I think the only limit would be what's the evidence? You know, the evidence right now is three spatial in one time. And there are proposals and suggestions for higher order dimensions, but are smaller. And that we'd have to access them at higher energy. But until we find them, you know, and, and once you figure out how to find them, there's no reason to cut it off. But it's what's the evidence?

• 47:20Neil deGrasse Tyson?

  If I found it, I'm not telling anybody. But, but just to be clear mathematically, there is no constraint on how many dimensions you can invoke in a, in a, in an equation or in a calculation.

• 47:31Speaker 01

  An infinite dimensional vector space.

• 47:34Neil deGrasse Tyson?

  Infinite dimensions.

• 47:36Harrison Greenbaum?

  But physically, I don't know. So then there can never be somebody beyond your, there can be an infinity plus one deity.

• 47:42Neil deGrasse Tyson?

  That you sound like a 10 year old kid. What's your biggest number you know? A billion, billion and one. Okay, infinity. Infinity and one. No, it's still infinity. You lose. It's not like you lost that a couple of times.

• 47:55Neil deGrasse Tyson?

  We gotta wrap this up. James, always good to have you.

• 47:58Harrison Greenbaum?

  Pleasure. Thanks.

• 47:59Neil deGrasse Tyson?

  Anyway, we can get you. Next time.

• 48:00Harrison Greenbaum?

  Good seeing you.

• 48:01Neil deGrasse Tyson?

  Next time you come through New York, just make sure to stop by. We will wrap a show around you.

• 48:05Harrison Greenbaum?

  Okay. Bring your action figures.

• 48:07Neil deGrasse Tyson?

  Yeah, right. And John, thanks for being on.

• 48:11Harrison Greenbaum?

  It was a great pleasure.

• 48:12Neil deGrasse Tyson?

  This is your first time on StarTalk?

• 48:13Harrison Greenbaum?

  It is, it is.

• 48:14Neil deGrasse Tyson?

  Okay. Well, we'll find a way to get back to you because I love me some math. And, and Harrison.

• 48:20Harrison Greenbaum?

  Yeah.

• 48:20Neil deGrasse Tyson?

  Welcome.

• 48:21Harrison Greenbaum?

  Thank you.

• 48:21Neil deGrasse Tyson?

  We'll get you back for sure.

• 48:23Harrison Greenbaum?

  Awesome.

• 48:23Neil deGrasse Tyson?

  And this has been StarTalk, the 4D Cosmic Queries Edition. I've been your host, Neil deGrasse Tyson, your personal astrophysicist, and as always, I bid you