Latest / Daniel and Kelly’s Extraordinary Universe / What Is A Dimension And How Many Are There?

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What Is A Dimension And How Many Are There? · Daniel and Kelly’s Extraordinary Universe

• 0:08
  Speaker 1: What if you could slip in and out of the
• 0:11
  Speaker 1: world you're currently in. Are you talking about like opening
• 0:14
  Speaker 1: a door to another dimension, because you know that's just
• 0:16
  Speaker 1: science fiction, right, is it really? Are you sure there
• 0:19
  Speaker 1: could be more to the world than the world we
• 0:21
  Speaker 1: see around us? You know, like there's this three D
• 0:24
  Speaker 1: world we live in, but maybe this world that we're
• 0:27
  Speaker 1: in actually kind of extends somewhere else. It's certainly true
• 0:31
  Speaker 1: that we know very little about how the universe works,
• 0:34
  Speaker 1: So there's the possibility to sort of blow things open
• 0:37
  Speaker 1: and discover that the universe is rich in ways we
• 0:40
  Speaker 1: hadn't imagined. And one of the highest candidates in my
• 0:42
  Speaker 1: mind is this concept that there might be other dimensions
• 0:45
  Speaker 1: to space and time. Well, I'm excited about this podcast.
• 0:48
  Speaker 1: I feel like it's going to add a whole new
• 0:51
  Speaker 1: dimension to our conversation. I feel like you worked way
• 0:55
  Speaker 1: too hard, but I laughed the theme the theme. So, Hi,
• 1:20
  Speaker 1: I'm Jorge and I'm Daniel, and we're at the authors
• 1:23
  Speaker 1: of the book We Have No Idea and this is
• 1:25
  Speaker 1: our podcast. Daniel and Jorge explain the universe today on
• 1:29
  Speaker 1: the podcast Extra Dimensions, Dimensions, dimensions and also non extra dimensions.
• 1:39
  Speaker 1: The ones you know and love and shake your booty
• 1:42
  Speaker 1: too on Friday nights. What is a dimensions? Right? There's
• 1:45
  Speaker 1: essential dimensions and then there's extra dimensions. I feel like
• 1:48
  Speaker 1: there's some sort of judgment you're making their like extra
• 1:50
  Speaker 1: like second class dimensions or not necessary dimensions, or if
• 1:54
  Speaker 1: you have to cut them away, you know, you could
• 1:56
  Speaker 1: just prune them out of your life without King twice.
• 1:58
  Speaker 1: You don't need him to make a podcast apparently. Actually,
• 2:01
  Speaker 1: I think, as you'll discover when we break this down,
• 2:03
  Speaker 1: explain what dimensions are. All the dimensions that exist are
• 2:06
  Speaker 1: absolutely essential for physics to work, and you know, physics
• 2:10
  Speaker 1: is for and fundamental. If physics doesn't work, nothing works. Yeah,
• 2:13
  Speaker 1: And these days I feel like we kind of need
• 2:15
  Speaker 1: an emergency dimension too, just in case, you know, you
• 2:18
  Speaker 1: mean you want a trap door you can slip into
• 2:20
  Speaker 1: some emergency dimension where nobody can hear, yeah, or you know,
• 2:23
  Speaker 1: just throw some extra heat from global warming or that
• 2:27
  Speaker 1: would be awesome, just like a venting dimension. Just dimension
• 2:34
  Speaker 1: you want to just have like a black circle on
• 2:36
  Speaker 1: the on the floor of your office where you can
• 2:38
  Speaker 1: press a button and suck anything you want into into
• 2:41
  Speaker 1: another dimension. But this is a really mind blowing topic
• 2:45
  Speaker 1: and really kind of challenges your what you know about
• 2:48
  Speaker 1: the world around you. We were curious about what people
• 2:51
  Speaker 1: out there thought about extra dimensions and how many of
• 2:55
  Speaker 1: them are there. Yeah, So I went around and I
• 2:57
  Speaker 1: asked people. I said, what is the dimension and how
• 3:00
  Speaker 1: many do you think there are? Here's what they had
• 3:02
  Speaker 1: to say. I'm not sure. If I was watching Interstellar,
• 3:07
  Speaker 1: I heard it was five dimensions, so I was like,
• 3:10
  Speaker 1: but realistic, realistic? I don't know. I heard of a
• 3:13
  Speaker 1: four dimensions, faith dimension. I don't know if anything beyond that.
• 3:17
  Speaker 1: I don't know a lot of the fifth dimension, the
• 3:20
  Speaker 1: sixth dimension, the movies we have seen right right, So
• 3:23
  Speaker 1: I mean using time as a conundrum, that can be
• 3:27
  Speaker 1: many dimensions and you can go from one dimension. No,
• 3:30
  Speaker 1: I don't know scientifically. I just know like fictionally, like
• 3:33
  Speaker 1: when they say there's like different dimensions, and I think
• 3:36
  Speaker 1: of like kind of like time traveling. But and I
• 3:40
  Speaker 1: don't know how many dimensions there are, all right, not
• 3:44
  Speaker 1: a lot of deep knowledge about dimensions, yes, definitely some
• 3:48
  Speaker 1: deep misunderstandings about what dimensions are. Some people out there
• 3:51
  Speaker 1: seem to have some concept, you know, that dimensions are
• 3:53
  Speaker 1: not universes, that they're not parallel places you can go to,
• 3:57
  Speaker 1: but that they're like a direction in space. So we
• 3:59
  Speaker 1: have some knowledge but also a lot of misconceptions. So
• 4:02
  Speaker 1: that totally motivates this podcast. We should really break this
• 4:05
  Speaker 1: down and explain from the beginning what is a dimension? Yeah,
• 4:08
  Speaker 1: because in science fiction you always see them talk about
• 4:11
  Speaker 1: dimensions that if it's like another parallel universe, you know,
• 4:15
  Speaker 1: like it's just like ours, but it's in another dimension,
• 4:18
  Speaker 1: creature from the other dimension. But that's kind of hard
• 4:21
  Speaker 1: to use normally, right, like in doorway to another dimension
• 4:24
  Speaker 1: and the version of you in another dimension. That's right,
• 4:28
  Speaker 1: it's really used to mean parallel universe. Yeah. Why do
• 4:31
  Speaker 1: you think science fiction writers started using that word dimension
• 4:34
  Speaker 1: for this concept of a parallel universe. I don't know,
• 4:37
  Speaker 1: And um I have a lot of things to say
• 4:39
  Speaker 1: about that, but I don't want to because I love
• 4:41
  Speaker 1: science fiction and I don't want to get on the
• 4:43
  Speaker 1: on the bad side of science fiction writers. UM. I
• 4:47
  Speaker 1: think a lot of times they don't have as deep
• 4:49
  Speaker 1: a grasp of the science as they think they do,
• 4:52
  Speaker 1: and they imagine they understand it, and so they end
• 4:54
  Speaker 1: up misusing a word. UM Like, I read a lot
• 4:57
  Speaker 1: of science fiction with the higgs boson in it, and
• 4:59
  Speaker 1: the higgs bos one in those fictional universes has nothing
• 5:02
  Speaker 1: in common with the higgs boson in our universe except
• 5:05
  Speaker 1: for like how it's spelled on the page. So I
• 5:09
  Speaker 1: think they appropriate terms the here in science and this
• 5:12
  Speaker 1: use them as for whatever plot device they need. Well,
• 5:17
  Speaker 1: let's break it down. So in science fiction and that
• 5:19
  Speaker 1: other mentioned means like a parallel universe, but in physics
• 5:23
  Speaker 1: it means something else, doesn't mean a whole another universe
• 5:26
  Speaker 1: means just another direction of space. Right, that's right. You
• 5:30
  Speaker 1: can think of the question what is a dimension as
• 5:32
  Speaker 1: another way of saying, like, how many numbers do you
• 5:35
  Speaker 1: need to specify where you are? Right? Imagine that you're
• 5:39
  Speaker 1: some being that lives on a string is a one
• 5:41
  Speaker 1: dimensional world. What that means is that there's only one
• 5:44
  Speaker 1: direction you can move, and so you can specify exactly
• 5:47
  Speaker 1: where you are in that world with just one number,
• 5:49
  Speaker 1: which is how far along you are in that string. Right.
• 5:52
  Speaker 1: Imagine like a ruler, a single ruler, and if you say, hey,
• 5:56
  Speaker 1: meet me at six point five, there's no other place
• 5:58
  Speaker 1: at six point five, right, You just need a number
• 6:00
  Speaker 1: to tell you where you are. On that string. It's
• 6:02
  Speaker 1: kind of like your coordin and it's in a GPS map,
• 6:05
  Speaker 1: Yeah exactly. Like in a flat map, you only need
• 6:07
  Speaker 1: two numbers right up and down to know where you
• 6:10
  Speaker 1: are on a flat map, Yeah exactly. So in one dimension,
• 6:13
  Speaker 1: need one number. In two dimensions, which is like a surface,
• 6:16
  Speaker 1: like a flat piece of paper or the surface of
• 6:18
  Speaker 1: the Earth, you need two numbers, right, for two dimensions.
• 6:21
  Speaker 1: So that's why you need like longitude and latitude. If
• 6:23
  Speaker 1: you're on a two dimensional surface like the surface of
• 6:26
  Speaker 1: the Earth, and you just tell somebody your latitude, like
• 6:28
  Speaker 1: meet me at this latitude, there's an infinite number of
• 6:31
  Speaker 1: places that have that latitude, it's not enough to specify
• 6:34
  Speaker 1: your location. So in two dimensions you need two numbers.
• 6:37
  Speaker 1: That's what dimension means, right, Being in two dimensional world
• 6:40
  Speaker 1: means you need two numbers to specify it, and so
• 6:44
  Speaker 1: three D means three dimensions means you need three numbers
• 6:47
  Speaker 1: to specify where you are, like not just wearing the map,
• 6:50
  Speaker 1: but also how high up you are. Yeah exactly. So
• 6:53
  Speaker 1: if you're flying an airplane, right, you need to know
• 6:55
  Speaker 1: exactly where you are longitude and latitude, but also your altitude. Right,
• 6:59
  Speaker 1: you need to know that would be important. Yeah, to
• 7:01
  Speaker 1: know that would be you don't crush two place together
• 7:04
  Speaker 1: or into a mountain or something, right, because you can
• 7:06
  Speaker 1: be at the same longitude and latitude but different altitudes
• 7:10
  Speaker 1: and so be quite safe. Right. So three dimensional world
• 7:13
  Speaker 1: needs three dimensions to specify where you are. So it's
• 7:16
  Speaker 1: mostly just about directions. So like instead of calling dimensions,
• 7:19
  Speaker 1: you could just call it directions, right kind of right,
• 7:21
  Speaker 1: like you could say, in our three D world, we
• 7:25
  Speaker 1: have up and down, left, right, forward backwards. Those are
• 7:28
  Speaker 1: the three main directions. Yeah, And and there's an important
• 7:32
  Speaker 1: concept there which is not just main directions but orthogonal directions,
• 7:36
  Speaker 1: directions that don't overlap, right, so they're moving in one
• 7:40
  Speaker 1: of them doesn't change your position in another. You mean,
• 7:43
  Speaker 1: they're like in a corner of a cube. You know,
• 7:45
  Speaker 1: there's ninety degrees between each direction. That's right, So imagine
• 7:49
  Speaker 1: yourself on a chessboard or something right, and you can
• 7:51
  Speaker 1: hop left or right just along one road doesn't change
• 7:54
  Speaker 1: which column you're on. That's because those two directions are
• 7:58
  Speaker 1: orthogonal there, they don't affect each other. You can move
• 8:00
  Speaker 1: independently in those two right. Now, you could put a
• 8:04
  Speaker 1: third dimension. On a piece of paper, you put a
• 8:06
  Speaker 1: third direction, like a diagonal direction, but then moving along
• 8:09
  Speaker 1: it would change your direction and the other two. So
• 8:11
  Speaker 1: that's how you know on a piece of paper that
• 8:13
  Speaker 1: there are only two dimensions, because there's no place to
• 8:15
  Speaker 1: add a third one. Oh, I see, they need to
• 8:17
  Speaker 1: be like totally independent directions exactly, exactly, got it. So
• 8:23
  Speaker 1: that's three dimensions, and so dimensions is kind of like directions.
• 8:26
  Speaker 1: So then if we add more dimensions, that means that
• 8:30
  Speaker 1: what does that even mean? Yes, So in order for
• 8:32
  Speaker 1: there to be more dimensions, and they have to be
• 8:34
  Speaker 1: more ways that you can move, right, it means that
• 8:37
  Speaker 1: specifying your position just with three numbers isn't enough. Right,
• 8:41
  Speaker 1: There's like another way that you can be at those
• 8:44
  Speaker 1: three places but not be on top of each other. Right,
• 8:47
  Speaker 1: it's space has this other way you can move. And
• 8:50
  Speaker 1: this is really hard to think about, right, because we
• 8:52
  Speaker 1: are used to being in a three dimensional world. We
• 8:54
  Speaker 1: understand depth and height and and and with and these
• 8:58
  Speaker 1: sort of ways to move. It's hard to imagine like
• 9:01
  Speaker 1: where things could go or where this dimension could be, Right,
• 9:05
  Speaker 1: But I think it's interesting to think about how long
• 9:07
  Speaker 1: people have been thinking that way. You know, I think, um,
• 9:10
  Speaker 1: thousands of years ago, people weren't thinking in terms of
• 9:14
  Speaker 1: three dimensions. The whole concept of dimensions is actually fairly
• 9:17
  Speaker 1: new and scientific, what I mean, you know, it's only
• 9:20
  Speaker 1: a few hundred years old. You know, Decartes came up
• 9:22
  Speaker 1: with Cartesian coordinates. He was the first person to really
• 9:25
  Speaker 1: lay this idea out that there was a space around
• 9:28
  Speaker 1: us and that you could define it mathematically in terms
• 9:31
  Speaker 1: of a few independent directions. Yeah, but like ancient civilizations,
• 9:35
  Speaker 1: they could build pyramids and buildings and columns and blogs, right,
• 9:39
  Speaker 1: And it's not like they thought in two D. Well,
• 9:41
  Speaker 1: it's not clear how they thought. I mean, they lived
• 9:43
  Speaker 1: in three D. Right, Certainly they lived in the world
• 9:45
  Speaker 1: and they could understand it. But look at their art,
• 9:47
  Speaker 1: you know, their art was really flat. The whole concept
• 9:50
  Speaker 1: of like perspective and geometry and art is only a
• 9:53
  Speaker 1: few hundred years old, and some people even think that
• 9:56
  Speaker 1: art might have led the way. You know that people
• 9:59
  Speaker 1: artists trying to figure out how to make an image
• 10:02
  Speaker 1: look accurate, develop this concept of perspective in order to
• 10:06
  Speaker 1: describe it. And it's out of that idea of perspective
• 10:09
  Speaker 1: and geometry change the way people thought about the space
• 10:12
  Speaker 1: in front of them mathematically speaking, you mean mathematically speaking, Yeah,
• 10:15
  Speaker 1: that they gave us a more mathematical view of the
• 10:18
  Speaker 1: very world we live in. And this is one of
• 10:21
  Speaker 1: the core problems is that it's hard to pull apart
• 10:24
  Speaker 1: the way you think and think about the ways you
• 10:26
  Speaker 1: could be thinking, right, other ways that you could imagine
• 10:29
  Speaker 1: the world, because it's so ingrained in it's just the
• 10:31
  Speaker 1: way you are. It's really difficult to imagine what would
• 10:34
  Speaker 1: you like to live in another country, or to use
• 10:36
  Speaker 1: another kind of toy let or whatever, right, because these
• 10:38
  Speaker 1: are just the way we live and we think it's
• 10:40
  Speaker 1: basic and inherent to everything, but it might not be so.
• 10:42
  Speaker 1: At some point somebody said, hey, hey, guys, wait a minute.
• 10:45
  Speaker 1: If we're going to do science, we we got to
• 10:47
  Speaker 1: think about these directions of space. Yeah, and the whole
• 10:50
  Speaker 1: concept of spaces is even kind of new. I mean,
• 10:52
  Speaker 1: Aristotle didn't believe in space. He thought everything was filled, right,
• 10:56
  Speaker 1: He's like, there's no void, everything is filled, there's no
• 10:59
  Speaker 1: gap between me and the air surrounding me. You know.
• 11:03
  Speaker 1: He didn't believe in atoms, right. He thought air was continuous, fluid,
• 11:07
  Speaker 1: and everything was continuous and the cold concept of like
• 11:11
  Speaker 1: a huge universe out there mostly empty was an anathema
• 11:15
  Speaker 1: to Aristotle, and you know, Aristotle was an influential dude,
• 11:18
  Speaker 1: So people thought that way for a long long time,
• 11:20
  Speaker 1: and it wasn't until much later the people embraced this
• 11:23
  Speaker 1: concept of space. And you know, Decarte invented this this
• 11:26
  Speaker 1: coordinate system, which now seems like totally trivial. Right. I
• 11:29
  Speaker 1: love these inventions in history where you're like, do dude
• 11:32
  Speaker 1: just wrote down X Y Z, and he's like a
• 11:34
  Speaker 1: genius and like a staggering genius, and the history of
• 11:37
  Speaker 1: intellectual thought, like it's so obvious, but that's a clue
• 11:41
  Speaker 1: that the concept was so deep and fundamental and insightful
• 11:44
  Speaker 1: that changed the way everybody thinks so much that you
• 11:46
  Speaker 1: can't even imagine another way. Right. It's like when you
• 11:49
  Speaker 1: see a joke in a movie, you wish you had
• 11:51
  Speaker 1: been born a few hundred years ago, so you could,
• 11:53
  Speaker 1: you know, become more famous a little bit more easily.
• 11:56
  Speaker 1: I don't think I would have been a man of
• 11:58
  Speaker 1: leisure and had the opportunity to do any science. Plus
• 12:01
  Speaker 1: a few years ago, like the food wasn't nearly as good.
• 12:03
  Speaker 1: So I'm pretty happy to be alive now, yeah, I
• 12:05
  Speaker 1: think the bathrooms were also less comfortable, and then the
• 12:09
  Speaker 1: broadband was terrible. Yeah. Um. But you know it's like
• 12:13
  Speaker 1: when you see trope in a movie and you're like, oh,
• 12:15
  Speaker 1: my god, what a cliche, and then you discover, oh,
• 12:17
  Speaker 1: this is the movie that invented that cliche, and actually
• 12:20
  Speaker 1: it's totally forward thinking. And at the time it was
• 12:23
  Speaker 1: it was a crazy idea, right, That's how crazy the
• 12:25
  Speaker 1: idea of dimensions was at the time. And then Newton
• 12:28
  Speaker 1: extended it to space. Right, he said, well, if the
• 12:31
  Speaker 1: laws of physics are the same on the Earth as
• 12:33
  Speaker 1: they are out in the cosmos, that these three dimensions
• 12:36
  Speaker 1: should extend all the way out and they could go
• 12:38
  Speaker 1: on forever. And so this whole concept of thinking of
• 12:41
  Speaker 1: the world around us is having three dimensions and that
• 12:43
  Speaker 1: we moved through it in this space is actually kind
• 12:46
  Speaker 1: of new. Okay, So we think that there are only
• 12:48
  Speaker 1: three dimensions in our world. I mean, that's why we're
• 12:51
  Speaker 1: used to We're used to only being able to move forward, backwards,
• 12:55
  Speaker 1: left and right, up and down. And so now this
• 12:57
  Speaker 1: idea is that maybe in the same universe that we're in,
• 13:01
  Speaker 1: you can also move in other directions that are sort
• 13:04
  Speaker 1: of invisible or not apparent to us right now. Yeah,
• 13:08
  Speaker 1: and so let's think that through, Like what would that
• 13:10
  Speaker 1: be like? And we talked at the top of the
• 13:12
  Speaker 1: program about you know, could you disappear into another dimension? Yeah,
• 13:15
  Speaker 1: let's get into it, but first let's take a quick break. Okay, So,
• 13:31
  Speaker 1: how can there be more than three dimensions around me
• 13:34
  Speaker 1: right now? How it is an even possible? Well, almost
• 13:36
  Speaker 1: anything is possible. I mean, we should take everything we
• 13:39
  Speaker 1: know about physics with a huge grain of salt, right
• 13:41
  Speaker 1: because everything we've learned is something we've learned by studying
• 13:44
  Speaker 1: a tiny little slice of the kinds of stuff in
• 13:46
  Speaker 1: the universe only around us here on Earth for the
• 13:49
  Speaker 1: last few decades. Basically, so a lot of things that
• 13:52
  Speaker 1: we think could be wrong. We should be prepared for
• 13:54
  Speaker 1: almost anything you think is fundamentally obviously true to be
• 13:58
  Speaker 1: overthrown by physics in the next few decades. Okay, so
• 14:00
  Speaker 1: you're saying physicists are salty A and B. Not even
• 14:06
  Speaker 1: the things we take for granted, like three dimensions we're
• 14:09
  Speaker 1: certain about. Is that what you're saying? That's right? In fact,
• 14:12
  Speaker 1: we're pretty sure there are more than three dimensions I mean,
• 14:15
  Speaker 1: no concrete proof, but if the world would make more
• 14:18
  Speaker 1: sense if there were more than three dimensions, Well, I
• 14:21
  Speaker 1: guess um. It's something we had in our book that
• 14:24
  Speaker 1: I always liked, was this idea that why only three dimensions? Yeah?
• 14:29
  Speaker 1: Like what is special about the number three? Right? Yeah?
• 14:32
  Speaker 1: Three is a weird number? Like there's no argument in
• 14:35
  Speaker 1: physics it says there must be only three dimensions. So
• 14:38
  Speaker 1: that's a weird thing. It's weird. And mathematicians don't like
• 14:41
  Speaker 1: the number three either, you know, they like simple numbers zero,
• 14:44
  Speaker 1: pie e, nobody, but the Catholic Church thinks that three
• 14:48
  Speaker 1: is a deep fundamental number in the universe. Right, Um,
• 14:51
  Speaker 1: why don't we think about, like what would be like
• 14:54
  Speaker 1: if we saw something that was four dimensional? Okay, so
• 14:58
  Speaker 1: I can move forward, backwards, left, right, up and down,
• 15:01
  Speaker 1: and I can also move in this other fourth dimension. Yeah,
• 15:04
  Speaker 1: let's invent a name for this fourth dimension. Okay, you're
• 15:07
  Speaker 1: the creative one, go ahead, Yeah, sure, red blue okay,
• 15:11
  Speaker 1: Marshamallow unicorn, marshallow unicorn. No, I like red and blue.
• 15:15
  Speaker 1: That's cool. So before we think about the fourth dimension,
• 15:18
  Speaker 1: that's practiced by thinking about three dimensions as if we
• 15:22
  Speaker 1: were two dimensional beings. Right, say we lived on the
• 15:24
  Speaker 1: surface of a piece of paper. Okay, so we're flat
• 15:28
  Speaker 1: Daniels flat Jorge talking on a flat podcast somehow delivered
• 15:31
  Speaker 1: to you. I mean like we're stuck in a comic book, yes,
• 15:34
  Speaker 1: exactly right, or a TV screen. Yeah, we are comic
• 15:37
  Speaker 1: characters on a comic page. Now, of course we live
• 15:40
  Speaker 1: in a three dimensional world. But as comic book characters,
• 15:43
  Speaker 1: we're not aware of that. We can only see our
• 15:44
  Speaker 1: two dimensions. Right, We're moving around inside the page, we're
• 15:48
  Speaker 1: walking around each other, we're bumping into each other, but
• 15:50
  Speaker 1: we're still stuck on the page. Yeah. Now, imagine what
• 15:53
  Speaker 1: happens if a three dimensional object passes through the page, right,
• 15:58
  Speaker 1: what do we sense? What is that like? For us
• 16:00
  Speaker 1: to experience a higher dimensional object, it would suddenly appear, right,
• 16:05
  Speaker 1: or if it was I guess, if it was a
• 16:06
  Speaker 1: like a sphere, like a ball going into our page,
• 16:09
  Speaker 1: if we would see first the dot, and then it
• 16:11
  Speaker 1: would get bigger and bigger and bigger, and then would
• 16:13
  Speaker 1: get smaller and smaller and smaller, like it would just
• 16:16
  Speaker 1: suddenly appear, yes, exactly, because it's moving in this dimension,
• 16:20
  Speaker 1: we can't understand or appreciate or measure, right, And so
• 16:24
  Speaker 1: we just see a slice of it. We see the
• 16:26
  Speaker 1: two dimensional slice of this three dimensional object, and that
• 16:29
  Speaker 1: slice is changing as it moves through this dimension that
• 16:32
  Speaker 1: we can't observe or notice. Right, So that's the useful strategy, right,
• 16:37
  Speaker 1: that's how you think about going up one dimension. So
• 16:40
  Speaker 1: now we're in a three dimensional world, right, maybe we're
• 16:42
  Speaker 1: three D people, flesh and blood, etcetera. And now imagine somebody,
• 16:47
  Speaker 1: a four dimensional being, passes a four dimensional sphere through
• 16:51
  Speaker 1: our universe. The analogy tells us that it would start
• 16:55
  Speaker 1: out looking like an object, appearing and then growing and
• 16:58
  Speaker 1: then shrinking, right, and um, so that's how you see
• 17:02
  Speaker 1: a higher dimensional object. You only observe your dimensional slice
• 17:06
  Speaker 1: of it. So we see a three dimensional slice of
• 17:08
  Speaker 1: a four dimensional sphere. It would do things that three
• 17:11
  Speaker 1: D spheres just can't do. You only see part of it,
• 17:14
  Speaker 1: that's right. Yeah, Because the three D slice has three dimensions, right,
• 17:17
  Speaker 1: it looks like a physical object, but because you can
• 17:20
  Speaker 1: move in this fourth dimension, it can do things that
• 17:22
  Speaker 1: make no sense to us. Right. It can seem to
• 17:24
  Speaker 1: disappear or change or grow or whatever. It's like. You
• 17:27
  Speaker 1: call it a slice but it's it could almost also
• 17:30
  Speaker 1: like the shadow or the projection of that thing in
• 17:33
  Speaker 1: our world. Oh I like that projection. Yeah, okay, so
• 17:37
  Speaker 1: that's what What would it? What would it feel like
• 17:39
  Speaker 1: for me to move in this other dimension? Like if
• 17:42
  Speaker 1: I'm sitting here talking to you and then suddenly I
• 17:44
  Speaker 1: decided to move in the other direction, what would that
• 17:47
  Speaker 1: be like? Well, if you are a three dimensional being
• 17:50
  Speaker 1: and you can only observe three dimensions, right, so you
• 17:52
  Speaker 1: can't tell where you are in this fourth dimension, then
• 17:56
  Speaker 1: you're going to be seeing different three D projections of
• 17:59
  Speaker 1: that four D world, and so the whole world around
• 18:02
  Speaker 1: you would change. It would change, Yeah, the same way
• 18:05
  Speaker 1: a four D object passing through your three D world
• 18:08
  Speaker 1: would shift and change in ways that don't make sense
• 18:10
  Speaker 1: to you. If you, as a three D object pass
• 18:13
  Speaker 1: through a four D world, then the whole world around
• 18:16
  Speaker 1: you could change. Like what does your house look like
• 18:19
  Speaker 1: in this fourth dimension? Is it the same? Does it change?
• 18:21
  Speaker 1: Does it disappear? Does it have a finite extent in
• 18:24
  Speaker 1: this fourth dimension? So that if you move through that
• 18:26
  Speaker 1: fourth dimension, your house disappears, right, and you're not observing
• 18:29
  Speaker 1: the whole thing. Okay, I'm getting a three D headache
• 18:33
  Speaker 1: you're getting exactly. Imagine a cartoon character walking through our world, right,
• 18:38
  Speaker 1: only perceiving in two dimensions. Things would suddenly appear to
• 18:41
  Speaker 1: them and disappear, and the whole world around them would
• 18:44
  Speaker 1: would be changing constantly. Would be very hard to understand. Oh,
• 18:47
  Speaker 1: I see. So you're saying, like, if I can move
• 18:49
  Speaker 1: in four dimensions, but maybe my house didn't have a
• 18:52
  Speaker 1: four dimensional aspect to it, then it would just disappear
• 18:56
  Speaker 1: once I moved to this other dimension. Yeah, like that
• 18:58
  Speaker 1: comment that two D comic book character jumping off the page, right,
• 19:02
  Speaker 1: if they can still only experience two D, then the
• 19:04
  Speaker 1: world around them, the comic world they've known and loved,
• 19:07
  Speaker 1: disappears instantly, right Wow. Okay, so then it could it
• 19:10
  Speaker 1: could be sort of like in science fiction where it's
• 19:12
  Speaker 1: a whole another world, right, Like not really a whole
• 19:15
  Speaker 1: another world. It's like it's a larger it's an expansion
• 19:19
  Speaker 1: of our world. We there were, we are a slice
• 19:21
  Speaker 1: of a larger world. Okay, I could change my red
• 19:26
  Speaker 1: blue coordinate and what if there's a whole another world
• 19:29
  Speaker 1: in another red Boudloe coordinate, then I would sort of
• 19:31
  Speaker 1: be moving to another world. Yeah. Absolutely, that could totally
• 19:36
  Speaker 1: scientifically actually happen, but there wouldn't be a door, and
• 19:39
  Speaker 1: there'd probably no marshmallows and no uniforms. But you know,
• 19:42
  Speaker 1: I can't guarantee. Like I said, we should be prepared
• 19:45
  Speaker 1: for everything. I think. I think all physics theories should
• 19:47
  Speaker 1: have the caveat. You know, not may pack your own marshmallows.
• 19:55
  Speaker 1: It's double footnote. Forget about the unicorns and the marshmallows.
• 20:00
  Speaker 1: B y o marshmallows. Okay, So it's all about kind
• 20:06
  Speaker 1: of like slices of reality and projections a reality. That's
• 20:09
  Speaker 1: what would be like to move between dimensions. Yeah, and
• 20:12
  Speaker 1: so if you're moving through these dimensions and things are changing,
• 20:14
  Speaker 1: then you have to build in your mind the sort
• 20:16
  Speaker 1: of four dimensional map of this space. You're like, Okay,
• 20:19
  Speaker 1: when I'm on the red end of this dimension, the
• 20:22
  Speaker 1: world looks like this. When I'm on the blue end,
• 20:23
  Speaker 1: the world looks like that, and then you can sort
• 20:25
  Speaker 1: of interpolate between and get an idea of how things
• 20:28
  Speaker 1: change as you move through this fourth red blue dimension. Right. Um,
• 20:32
  Speaker 1: but you have a little bit of practice with that already,
• 20:34
  Speaker 1: because in some sense you already know how to move
• 20:37
  Speaker 1: through a fourth dimension and that's time right, oh, right,
• 20:40
  Speaker 1: time people, something's call it the fourth dimension. Yeah, exactly.
• 20:44
  Speaker 1: If you think about time as another dimension, like a
• 20:47
  Speaker 1: direction you can move, it's a good practice because moving
• 20:51
  Speaker 1: through time is different from moving in like X, y
• 20:53
  Speaker 1: or z. Right, there's no replacing one with the other.
• 20:56
  Speaker 1: It's something like you can do it while standing still. Yes, exactly,
• 20:59
  Speaker 1: it's into pendent right. And really to specify where you
• 21:02
  Speaker 1: are you need to say when. Also, you can't say, hey,
• 21:05
  Speaker 1: meet me at Lexington and Fourth Avenue, you know, Um,
• 21:08
  Speaker 1: you have to say, well tomorrow, next year, yesterday, like
• 21:12
  Speaker 1: when are we meeting? Right, um? So you really do
• 21:15
  Speaker 1: need to specify time. And also it's in this time direction.
• 21:19
  Speaker 1: You're used to the world changing, Like the world is
• 21:21
  Speaker 1: different now than it was a hundred years ago, and
• 21:23
  Speaker 1: it will be different in a hundred years. The whole
• 21:25
  Speaker 1: three D world does evolve through time, and you're used
• 21:28
  Speaker 1: to sort of making a understanding of the world through time.
• 21:32
  Speaker 1: So it's not that much of a brain meld to
• 21:35
  Speaker 1: think that the world is changing through this fourth dimension
• 21:38
  Speaker 1: because you're you're used to doing that a little bit
• 21:40
  Speaker 1: with time. It's kind of like a videotape of view,
• 21:43
  Speaker 1: scrub it back and forth. If you hit rewinding for
• 21:45
  Speaker 1: it's backwards. It's like the world changes, but it doesn't move.
• 21:49
  Speaker 1: That's right exactly. And you know, listen to our podcast
• 21:52
  Speaker 1: about time travel to know how time is different from
• 21:55
  Speaker 1: the other dimensions. Rights like another dimension, but it's not
• 21:58
  Speaker 1: actually like another dimension. Right, has all sorts of special
• 22:01
  Speaker 1: rules and we don't understand it at all. And one
• 22:03
  Speaker 1: of these days we're gonna have time to sit down
• 22:05
  Speaker 1: and do a whole podcast about how time is weird.
• 22:08
  Speaker 1: But that's not the time for today. We'll run out
• 22:10
  Speaker 1: of time time after time. Cool. Well, I guess the
• 22:15
  Speaker 1: question is why are we even entertaining these crazy ideas
• 22:18
  Speaker 1: about dimensions? Like what makes us think that there could
• 22:22
  Speaker 1: be more dimensions than the three we're in? Yeah, that's
• 22:25
  Speaker 1: a great question. But before we get into it, let's
• 22:28
  Speaker 1: take a quick break. What makes physicists think that there's
• 22:44
  Speaker 1: more than three dimensions in our universe? Well? Number one,
• 22:47
  Speaker 1: physicists hope there's more dimensions because that would be like
• 22:49
  Speaker 1: a crazy discovery and awesome and like mind blowing is
• 22:53
  Speaker 1: there it could be more funding in that other dimensions
• 22:56
  Speaker 1: like a product cats, Right, that's right, or you just
• 22:58
  Speaker 1: have more lab space or something. So it's just it's
• 23:01
  Speaker 1: like on the list of crazy ideas you would love
• 23:04
  Speaker 1: to discover because it reveals the universe. It's different from
• 23:06
  Speaker 1: the way you always thought it was. And nobody said
• 23:09
  Speaker 1: there can be more dimensions, and so therefore it's tantalizing
• 23:12
  Speaker 1: to be the one who discovers it. That's right, But
• 23:14
  Speaker 1: it's more than that. We have some concrete hints that
• 23:16
  Speaker 1: there might be more dimensions. And hint number one is
• 23:19
  Speaker 1: this the unification of space and time into a concept
• 23:23
  Speaker 1: called space time, right, And this is Albert Einstein. More
• 23:26
  Speaker 1: than a years ago. He noticed that if you think
• 23:29
  Speaker 1: of space and time together as one four dimensional world, right,
• 23:33
  Speaker 1: that's a lot of things mathematically make a lot of sense. Um,
• 23:37
  Speaker 1: things just sort of unify. But most importantly, it helps
• 23:40
  Speaker 1: us understand what gravity is. Right. So we're used to
• 23:43
  Speaker 1: thinking of forces, and space is totally different. Right. Force
• 23:48
  Speaker 1: of gravity is something that pulls you through space, pushes
• 23:51
  Speaker 1: you away, or whatever. Um, it helps you move through space.
• 23:54
  Speaker 1: But Einstein, by bringing time and space together into space time,
• 23:58
  Speaker 1: made this argument that act truly, gravity is not a force.
• 24:02
  Speaker 1: It's just a bending of space. Right, You curve space
• 24:05
  Speaker 1: in a certain way, and then it's very natural for
• 24:07
  Speaker 1: the Earth to go around the Sun or the Earth
• 24:09
  Speaker 1: makes a bending of space, and so gravity is just
• 24:12
  Speaker 1: you sort of falling into the well that the Earth
• 24:15
  Speaker 1: makes in space. Right. So Si Einstein said, hey, actually
• 24:19
  Speaker 1: there are aren't Actually there aren't three dimensions. There's actually four,
• 24:23
  Speaker 1: and so that's kind of kick things off. That kicks
• 24:25
  Speaker 1: things off. And then people thought, well, if you can
• 24:28
  Speaker 1: explain gravity, this force we all know and love, in
• 24:31
  Speaker 1: terms of other dimensions, can we explain the other forces
• 24:34
  Speaker 1: in terms of other dimensions? Right? And so guys said, well,
• 24:37
  Speaker 1: if you make five dimensions, then you can kind of
• 24:40
  Speaker 1: explain electromagnetism, Like maybe electromagnetism isn't the force either, it's
• 24:44
  Speaker 1: just a way of bending in five dimensions. And then
• 24:49
  Speaker 1: to explain the other forces, you add another dimension. Other forces,
• 24:52
  Speaker 1: you add another dimension, meaning like the reason two magnets
• 24:56
  Speaker 1: are attracted to each other, it's not some kind of
• 24:58
  Speaker 1: magical force, it's just that in this if dimension they
• 25:01
  Speaker 1: want to be together. Yeah, Or that magnets are the
• 25:05
  Speaker 1: manifestation of space five dimensional space getting bent in such
• 25:09
  Speaker 1: a way that it's the most natural thing for these
• 25:12
  Speaker 1: things to do slide together or to be pushed apart,
• 25:14
  Speaker 1: and exactly the way the gravity is a bending of
• 25:17
  Speaker 1: four dimensional space. Maybe the idea goes that space has
• 25:22
  Speaker 1: more dimensions eight, nine, ten, eleven. This is why you
• 25:25
  Speaker 1: might hear sometimes that space might have eleven dimensions, ten spatials,
• 25:30
  Speaker 1: ten physical dimensions of motion, and one for time. Let's
• 25:33
  Speaker 1: just go for the Baker's dozen, you know, why not?
• 25:37
  Speaker 1: This is not like an auction or where we saying
• 25:40
  Speaker 1: let's figure out what the universe is. I hear twelve
• 25:42
  Speaker 1: going once, let's do anybody for thirteen. That's not how
• 25:45
  Speaker 1: That's not how physics conferences go. No, No, you've been
• 25:48
  Speaker 1: out of academia a little too long, I think. For Hey,
• 25:51
  Speaker 1: that's not the way we figure out the way the
• 25:52
  Speaker 1: world works. Um, it's not like the prices, right, you know,
• 25:55
  Speaker 1: who can get the closest without going over Welcome to
• 25:59
  Speaker 1: physics the game show. But it turns out, if you
• 26:04
  Speaker 1: want to explain the four fundamental forces we have, right, gravity, electromagnetism,
• 26:09
  Speaker 1: the weak force, and the strong force, you need ten
• 26:12
  Speaker 1: physical dimensions, ten dimensions of motion, and one dimension of time. Really, like,
• 26:18
  Speaker 1: that's part of the current theory of physics is that
• 26:20
  Speaker 1: there are eleven dimensions. That's one theory of physics. Yeah,
• 26:23
  Speaker 1: it's um theory that involves strings. Right. So string theory
• 26:27
  Speaker 1: maybe you've heard of, and it says that the universe
• 26:30
  Speaker 1: has ten dimensions and that three of them are physical
• 26:32
  Speaker 1: that we can move through, and that the other ones
• 26:35
  Speaker 1: are ways that the universe can bend, that the space
• 26:38
  Speaker 1: can bend. That explains what forces are. Really I never
• 26:42
  Speaker 1: knew that about string theory, is that it's it uses
• 26:45
  Speaker 1: these dimensions to explain the other forces. Yeah. Yeah, And
• 26:50
  Speaker 1: you know, the's a lot of questions. They're like, why
• 26:52
  Speaker 1: are these three dimensions seem to be infinite and orthogonal
• 26:55
  Speaker 1: and physical and the other dimensions are like these curled
• 26:59
  Speaker 1: up little rink that you can't like notice or move through. Mean,
• 27:02
  Speaker 1: somebody out there might be saying, Okay, maybe there are
• 27:05
  Speaker 1: ten dimensions. How do I move through those? Why can't
• 27:07
  Speaker 1: I notice them? Um? You know what's going on with
• 27:10
  Speaker 1: those other dimensions? Even if they do explain the forces,
• 27:13
  Speaker 1: where are they? Right? And the thing is that the
• 27:16
  Speaker 1: dimensions that we know and love X, Y and Z
• 27:19
  Speaker 1: might be different from those dimensions because X, Y and Z.
• 27:22
  Speaker 1: We think go on forever. I mean, we don't know
• 27:24
  Speaker 1: how long the universe goes, meaning they don't have to
• 27:26
  Speaker 1: be straight, right, like another fifth dimension, sixth dimension. It
• 27:31
  Speaker 1: could be like a little curly loop where it could
• 27:34
  Speaker 1: be who knows, right, that's right, we don't even know
• 27:36
  Speaker 1: about X, Y, Z if they eventually curl around themselves
• 27:39
  Speaker 1: and come back to where you started. We don't know
• 27:41
  Speaker 1: if you go straight forever, if you run out of
• 27:44
  Speaker 1: space or come back to where you started. But let's
• 27:46
  Speaker 1: assume for now that X, Y and Z go on forever.
• 27:49
  Speaker 1: The universe is infinite, and you know, and there's an
• 27:51
  Speaker 1: infinite number of locations in X, Y and Z, and
• 27:53
  Speaker 1: you can go on forever and never come back to
• 27:55
  Speaker 1: where you started. That's probably not true for the other dimensions.
• 27:58
  Speaker 1: The other dimensions were pretty sure are rolled up little curls,
• 28:03
  Speaker 1: tiny tiny little curls like ten to the minus thirty
• 28:06
  Speaker 1: centimeters or tend of the minus ten centimeters, meaning like
• 28:10
  Speaker 1: like if my coffee cup suddenly took off and went
• 28:12
  Speaker 1: off into this one of these other dimensions, it would
• 28:15
  Speaker 1: just make a little loop, like it would disappear and
• 28:17
  Speaker 1: then come back. Yeah, that there aren't many places to
• 28:19
  Speaker 1: go in these other dimensions. And also we don't even
• 28:23
  Speaker 1: really know what it would be like to notice those dimensions.
• 28:25
  Speaker 1: I mean, um, if those dimensions don't play our role
• 28:29
  Speaker 1: in our lives, then you know we have and we
• 28:31
  Speaker 1: have no senses in which to detect motion in those dimensions.
• 28:35
  Speaker 1: And also of motion of those dimensions is really limited
• 28:37
  Speaker 1: because they're really super duper tiny, then you might not
• 28:39
  Speaker 1: even notice, right. The takeaway is that those other dimensions,
• 28:43
  Speaker 1: if they exist, are really small, um and looped up
• 28:47
  Speaker 1: on themselves. So they're really different from the kind of
• 28:49
  Speaker 1: dimensions were familiar. So well, physicists suspect that there are
• 28:53
  Speaker 1: dimensions of space. They're probably not the dimensions you can
• 28:55
  Speaker 1: move through or extend your house into, or go and
• 28:58
  Speaker 1: gallop on unicorns. While problem wouldn't be like the ones
• 29:03
  Speaker 1: that we have and know about. They'll be really weird
• 29:06
  Speaker 1: and different, pretty small, yeah, And so mostly they would
• 29:10
  Speaker 1: confirm like our understanding of the way forces work. And
• 29:13
  Speaker 1: maybe string theory, and you know, there's a bunch of
• 29:15
  Speaker 1: variants of string theory. Uh, there's one variant of string
• 29:18
  Speaker 1: theory called bosonic string theory that suggests twenty six dimensions
• 29:21
  Speaker 1: in order to get all the math to work out
• 29:23
  Speaker 1: really really nicely. How do they pick these numbers? Is
• 29:26
  Speaker 1: it just from the math or they I don't think
• 29:29
  Speaker 1: they're just like, you know, going out for froli and
• 29:31
  Speaker 1: being doing like, hey man, how many dimensions you think
• 29:33
  Speaker 1: there are today? Is that your model of how physics
• 29:37
  Speaker 1: is happening? But guess what I mean? It's like twenty
• 29:39
  Speaker 1: six makes the math work, but twenty seven and twenty
• 29:41
  Speaker 1: five do not. That's kind of exactly exactly. I think
• 29:45
  Speaker 1: the game is what's the minimum number of dimensions you
• 29:48
  Speaker 1: need to make the math work to make the theory
• 29:50
  Speaker 1: come together to have a universe that makes sense. So
• 29:52
  Speaker 1: it kind of seems like all the dimensions we have,
• 29:56
  Speaker 1: that's that's it. That's we can't escape to another universe
• 29:59
  Speaker 1: or other world, or we're kind of stuck with this reality.
• 30:02
  Speaker 1: Hey is this reality is so bad? Or hey man,
• 30:04
  Speaker 1: you're impressing me. You mean like, hey, this is an
• 30:07
  Speaker 1: awesome reality. I'm glad we're stuck with this awesome and
• 30:09
  Speaker 1: amazing reality. We have to spend at all day looking
• 30:12
  Speaker 1: at the pressing news articles. They will be good news
• 30:17
  Speaker 1: one day in this dimension getting and there's all sorts
• 30:21
  Speaker 1: of other fascinating things we get to in another episode
• 30:23
  Speaker 1: of the podcast, which can talk about like why these
• 30:26
  Speaker 1: dimensions can explain mysteries like why is gravity so weak?
• 30:30
  Speaker 1: It's so much weaker than the other forces, and can
• 30:33
  Speaker 1: we make black holes in the large Hadron Collider? All
• 30:36
  Speaker 1: these really fascinating things could be explained by having other
• 30:39
  Speaker 1: dimensions of space and time and having them be rolled
• 30:42
  Speaker 1: up and curled up. It can even explain why how
• 30:44
  Speaker 1: farts moved through the universe. Why what it could explain
• 30:47
  Speaker 1: how farts moved through the universe. And you're like what,
• 30:52
  Speaker 1: You're like, stop paying attention there, he said, from here
• 30:59
  Speaker 1: you know about fart physics. Of fart physics is a
• 31:01
  Speaker 1: whole new growing field. Yeah. To put it in perspective, right,
• 31:09
  Speaker 1: remember that the universe that you think you understand, it's
• 31:12
  Speaker 1: definitely not the universe that we live in. Right. The
• 31:15
  Speaker 1: universe we live in is more complicated and richer and
• 31:17
  Speaker 1: fascinating than you can probably even imagine. And sometimes we
• 31:21
  Speaker 1: get these crazy glimpses of other possible theories of how
• 31:24
  Speaker 1: the universe could work, and they might actually work that way,
• 31:26
  Speaker 1: and and one day we hope physics will crack them
• 31:28
  Speaker 1: open and reveal to us the universe is strange and
• 31:31
  Speaker 1: bizarre and beautiful in ways that we can we really
• 31:33
  Speaker 1: have a hard time even understanding. Yeah, and you'll discover
• 31:37
  Speaker 1: there's more sites to it than you think. Yeah, and
• 31:40
  Speaker 1: one day you will eat a four D marshmallow. That's right,
• 31:43
  Speaker 1: writing a unicorn. Yeah, how many sides are there on
• 31:47
  Speaker 1: a four D marshmallow? I mean three D marshmallows a
• 31:49
  Speaker 1: three D c right, so it's a four D hyper moment. Actually,
• 31:52
  Speaker 1: marshmallow only has two D s right, like two flat
• 31:55
  Speaker 1: ends in one cylinder. What are you saying marshmallows are cylinders?
• 31:59
  Speaker 1: I think I thought marshmallows were cubes. Did I just
• 32:01
  Speaker 1: blow your mind? You just taught me the universe is
• 32:04
  Speaker 1: different from what I always thought it was. Yeah, there's
• 32:06
  Speaker 1: always something's more to the universe. No, that was terrible
• 32:14
  Speaker 1: slash wonderful. The four D version of that joke really
• 32:18
  Speaker 1: is hilarious. Thank you everyone for listening. This has been
• 32:21
  Speaker 1: a mind blowing experience in other dimensions. See you next time.
• 32:33
  Speaker 1: If you still have a question after listening to all
• 32:36
  Speaker 1: these explanations, please drop us a line. We'd love to
• 32:39
  Speaker 1: hear from you. You can find us at Facebook, Twitter,
• 32:41
  Speaker 1: and Instagram at Daniel and Jorge That's One Word, or
• 32:45
  Speaker 1: email us at Feedback at Daniel and Jorge dot com