Latest / Daniel and Kelly’s Extraordinary Universe / What is the strongest magnet in the universe?

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What is the strongest magnet in the universe? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Daniel, what do you think is the most physics
0:10
Speaker 1: inspired superhero in TV or movies or comics. Oh? I'm
0:15
Speaker 1: a big fan of Magneto, and not just because I
0:17
Speaker 1: like Michael Fassbender, but because he can control magnets. Well,
0:21
Speaker 1: does he technically control magnets or is he like a
0:25
Speaker 1: like a magnet? He's got a magnetic personality. But the
0:28
Speaker 1: thing I like about it is that he can't just
0:30
Speaker 1: like move metal around. They actually thought about the physics
0:33
Speaker 1: of it. He has power over magnetic fields. But wait,
0:36
Speaker 1: isn't he a villain? Doesn't that make physics the science
0:39
Speaker 1: of bad guys? It just means, hey, you better give
0:42
Speaker 1: physics some respect or watch out. Well, I would have
0:45
Speaker 1: to say, Michael Fastbender is pretty attractive and magnetic, as
0:49
Speaker 1: is Ian McKellen. I'm surprised he didn't go to the
0:51
Speaker 1: Ian McKellen version of Magneto. I'm surprised you didn't include
0:55
Speaker 1: physicists on your list of attractive people. Well, I yes, yeah,
1:00
Speaker 1: I guess magnet's repulse as well. So there's a yin
1:05
Speaker 1: and a yang to everything. But break it down for us,
1:09
Speaker 1: what is the physics of Magneto? Yeah, that's basically it.
1:12
Speaker 1: He can control magnetic fields, and that's why in the
1:15
Speaker 1: movies you see him lifting anything with metal in it
1:18
Speaker 1: he can control because of course magnetic fields can control
1:21
Speaker 1: things that are conductors that can transmit electricity like metal.
1:25
Speaker 1: So is that why you became a physicist to try
1:27
Speaker 1: to be a supervillain. Yeah, I wanted to super repel everybody.
1:31
Speaker 1: Well it worked, no, because I think physics is kind
1:34
Speaker 1: of a superpower. I mean, it helps us understand the
1:37
Speaker 1: universe and then bend it to our will in certain
1:40
Speaker 1: maniacal cockle. Here, Hi am Morey. I'm a cartoonist and
2:01
Speaker 1: the creator of PhD Comics. Hi, I'm Daniel. I'm a
2:05
Speaker 1: particle physicist and I'm not a superhero. And together with
2:08
Speaker 1: the authors of the book, we have No Idea a
2:10
Speaker 1: guide to the Unknown Universe, which inspired this podcast. That's right.
2:15
Speaker 1: It's filled with all the questions about the universe that
2:17
Speaker 1: we don't know the answers to, and so we didn't
2:20
Speaker 1: put them in the book, but you can listen to
2:22
Speaker 1: them right now. Welcome to our podcast, Daniel and Jorge
2:25
Speaker 1: Explain the Universe, a production of My Heart Radio. That's right,
2:29
Speaker 1: our podcast and which we think about all the big
2:31
Speaker 1: questions of the universe and tell you what science does
2:34
Speaker 1: and does not know about them in a way that
2:36
Speaker 1: we hope educates you and makes you laugh. Yeah, all
2:39
Speaker 1: the everyday physics in your life, and also all the
2:41
Speaker 1: extreme things out there in the universe. That's right, the
2:44
Speaker 1: attractive stuff and the repulsive stuff. And so today we
2:48
Speaker 1: are continuing our series of podcasts about universal extremes or
2:53
Speaker 1: the extremes of the universe. That's right. And these are
2:56
Speaker 1: some of my favorite podcast because they really help us
2:59
Speaker 1: understand a context of the Earth and human life and
3:02
Speaker 1: your experience, and how everything you thought was amazing on
3:06
Speaker 1: Earth is actually kind of pathetic when you stack it
3:08
Speaker 1: up against what's going on in the rest of the universe. Wait,
3:11
Speaker 1: are we going to do the same joke we always
3:12
Speaker 1: do the extreme heavy metal riff. That's right, we are doing.
3:18
Speaker 1: We're drinking mountain dew and talking about the universe extreme universe,
3:24
Speaker 1: listening to Metallica in the background. That's right. This is
3:27
Speaker 1: just us pandering to be um the official podcast of
3:30
Speaker 1: the Next Bill and Ted excellent Adventure movie. I wish
3:34
Speaker 1: it should have right, we should have them on. Yeah,
3:38
Speaker 1: don't you know, Kanu I I know someone who knows
3:40
Speaker 1: Kanu more importantly, the the other guy. Um goes the
3:47
Speaker 1: other guy. It's Kanu and the other guy. Is that
3:49
Speaker 1: how you're going to get him to show up? Hey,
3:51
Speaker 1: other guy, would you like to be on our podcast?
3:53
Speaker 1: It's all about extreme universe? Well we should talk about
3:56
Speaker 1: this offline, but he does live in South past at
4:00
Speaker 1: and I've seen him around. All right, Well, Bill and
4:02
Speaker 1: or Ted and or the other guy. And if you
4:05
Speaker 1: want to appear on our podcast and talk about the
4:07
Speaker 1: extreme universe for your awesome new movie, you are welcome
4:10
Speaker 1: to sign up. And so today we'll be covering another
4:13
Speaker 1: universal extreme and one that is very It's a topic
4:17
Speaker 1: that's very attractive, right and magnetic and simultaneously repulsive. But
4:23
Speaker 1: it really, it really does capture something awesome about physics
4:26
Speaker 1: because this particular element of physics is something that really
4:29
Speaker 1: pulled me in as a kid. I mean, I remember
4:31
Speaker 1: playing with magnets as a kid and feeling like they
4:33
Speaker 1: were kind of a superpower, getting them to push against
4:36
Speaker 1: each other and one float above the other. It feels
4:39
Speaker 1: kind of like magic. Yeah, it is pretty magical. So
4:42
Speaker 1: today on the podcast, we'll be talking about what is
4:50
Speaker 1: the strongest magnet in the universe, in the entire universe, exactly,
4:56
Speaker 1: the strongest, most magnetic, most crazy magnet there that physics
5:01
Speaker 1: can come up with. That's right, And spoiler alert, the
5:04
Speaker 1: strongest magnet in the universe is not your brain. You
5:09
Speaker 1: mean my brain or our listeners brains. I mean the
5:11
Speaker 1: average brain. But you might be surprised to learn that
5:14
Speaker 1: your brain actually is a magnet. Really interesting. Yeah, well,
5:18
Speaker 1: you know, one of the things about physics that we've
5:20
Speaker 1: learned the last hundred years is this deep connection between
5:22
Speaker 1: electricity and magnetism. They're basically the same thing. And so
5:26
Speaker 1: anytime you have electrical currents, you're going to get magnetic fields.
5:30
Speaker 1: And what's going on in your brain? How do nerves work?
5:33
Speaker 1: How does this whole model of the crazy universe that
5:35
Speaker 1: you understand and you're the way you appreciate jokes and humor,
5:38
Speaker 1: how does that all work? It's electrical firings in your brain. Interesting,
5:42
Speaker 1: you're saying, because we have currents in our brain, therefore
5:45
Speaker 1: we do sort of generate magnetic fields. That's right, not
5:49
Speaker 1: sort of. If you think hard enough, you can wipe
5:51
Speaker 1: the credit cards out of your wallet. Well, I don't
5:55
Speaker 1: need my brain to my credit. But um, but even so,
5:59
Speaker 1: but brains work with like ion channels, right and not
6:02
Speaker 1: necessarily electrons. That also creates magnetic field. That's right. Every
6:06
Speaker 1: charged particle, any current, any moving charged particle will create
6:10
Speaker 1: a magnetic field. And so these magnetic fields we're talking about,
6:13
Speaker 1: they're not very impressive. They can't actually erase credit cards
6:16
Speaker 1: if you think about them correctly. But there is a
6:18
Speaker 1: magnetic field in your brain. And the unit we use
6:21
Speaker 1: for magnetic field is pretty cool. It's the Tesla Like
6:24
Speaker 1: how many cars it can move? No, you know, Tesla?
6:29
Speaker 1: How many can you can you get? The girl mustache? Like? Tesla? Know?
6:34
Speaker 1: How many startups can you start in one year? That's
6:37
Speaker 1: when Tesla um No, Tesla of Corps much predates the company, right.
6:42
Speaker 1: The company is named after the inventor and physicist and
6:45
Speaker 1: staggering genius Nikolai Tesla, And he was an early pioneer
6:49
Speaker 1: in and understanding electricity and magnetism, and so they named
6:53
Speaker 1: this unit of magnetization after him. When they named after him,
6:56
Speaker 1: or he named it, like he's the one who started
6:58
Speaker 1: measuring magnets. That's a good question the history of the
7:02
Speaker 1: the Tesla unit. I'm gonna have to look that up later,
7:04
Speaker 1: but I'm pretty sure it was named after him posthumously.
7:07
Speaker 1: I don't know if you can have a unit named
7:08
Speaker 1: after you while you're still alive. I think it's kind
7:10
Speaker 1: of like stamps. It's a bad form. I can discover
7:15
Speaker 1: this amazing thing, I'm gonna name it the whore, somebody
7:18
Speaker 1: else has to name it after you, right, That's the
7:20
Speaker 1: way these things usually work. One tesla is a pretty
7:24
Speaker 1: serious magnet. And so for example, like a fridge magnet
7:28
Speaker 1: that you have, you know, in your fridge that holds
7:30
Speaker 1: up your piece of paper whatever, that's like ten to
7:33
Speaker 1: the minus three tesla. It's like you need a thousand
7:36
Speaker 1: of those um to make one point oh oh one tesla.
7:40
Speaker 1: He's a fridge magnet, yeah, exactly. And your brain is
7:45
Speaker 1: tend to the minus twelve tesla, so it really doesn't
7:48
Speaker 1: even register. It's like one trillionth of a tesla, meaning
7:51
Speaker 1: like if you are were to measure the magnetic field
7:54
Speaker 1: in my head, you know, around my head, that's how
7:57
Speaker 1: strong it would be. And you know, I don't know
7:59
Speaker 1: how they got this number, and like stick probes in
8:01
Speaker 1: somebody's head, like somebody signed up to be that experiment. Um,
8:04
Speaker 1: I'm not quite sure, but I guess they must, because
8:06
Speaker 1: you know, they do do these experiments when they stick
8:08
Speaker 1: probes and people's heads. And so somebody decided to measure
8:10
Speaker 1: the magnetic field of the brain. But it's weak, but
8:13
Speaker 1: it's there. Meaning if I stand next to a fridge,
8:16
Speaker 1: I lit, my head is sort of attracted to the fridge.
8:19
Speaker 1: That's right. That's why you keep going back to the fridge.
8:22
Speaker 1: It's not your stomach, it's your head exactly. The head
8:26
Speaker 1: keeps pulling you into the fridge. Um. Yeah, no, but
8:29
Speaker 1: really right, that's what you're saying, right, Like, Um, there
8:31
Speaker 1: is some attraction between my brain and pieces of metal.
8:35
Speaker 1: That's true, Yes, there is some attraction. And um, that's
8:37
Speaker 1: basically you know, the core physics behind inventing a mutant
8:41
Speaker 1: that could actually become magneto. Right if you somehow had
8:45
Speaker 1: a brain which with super strong currents in it that
8:48
Speaker 1: generated really strong magnetic fields and could control them somehow,
8:51
Speaker 1: you know, dot dot dot, Um, you have magneto. Interesting,
8:56
Speaker 1: could any humans do that? You know? Like, you know,
8:58
Speaker 1: if I figure out how to align all the current
9:00
Speaker 1: in my brain, could increase the magnetic field. If you've
9:03
Speaker 1: got a trillion humans and lined up their brains, then
9:07
Speaker 1: then yeah, maybe you could be as strong as a
9:09
Speaker 1: pretty weak magnet. I'm not sure that's the best use
9:10
Speaker 1: of a trillion humans, but you're saying basically, anything with
9:13
Speaker 1: a current as can have a magnetic field. So even
9:16
Speaker 1: your toaster as a magnet. That's right. And it turns
9:19
Speaker 1: out your toaster has a magnetic it's about ten thousand
9:22
Speaker 1: times stronger than your brain. There's not that many things,
9:25
Speaker 1: ten thou, that's not that many things that your toaster
9:27
Speaker 1: can do better than your brain. One thing is toast bread.
9:30
Speaker 1: The other thing is make a magnetic few a toastbread
9:35
Speaker 1: be burned that in your house. That's right, and none
9:39
Speaker 1: of these are very strong compared to, of course, the
9:41
Speaker 1: Earth's magnetic field. The earth magnetic field is like thirty
9:45
Speaker 1: to sixty micro tesla. Okay, so that's pretty weak though, right,
9:50
Speaker 1: isn't it. That's pretty weaker than a fridge magnet. Yeah,
9:52
Speaker 1: that's right. A fridge magnet is also about ten to
9:54
Speaker 1: the mine is three tesla. And that's why, for example,
9:57
Speaker 1: when you make when you have a compass, you need
9:58
Speaker 1: to really find little filament. It has to be balanced
10:01
Speaker 1: on that needle because the magnetic force from the Earth's
10:04
Speaker 1: magnetic field is not very strong, right, it's you don't
10:08
Speaker 1: notice it if it's magnet's just sitting on the counter,
10:10
Speaker 1: doesn't like slide up or rotate towards the Earth's magnetic field.
10:14
Speaker 1: You need a very small piece of metal that can
10:16
Speaker 1: align with earth magnetic field because it's not a strong force. Alright,
10:20
Speaker 1: So today we'll be getting into magnetism and what is
10:23
Speaker 1: the strongest magnet in the universe. And it's I think
10:26
Speaker 1: feel like it's something interesting because not just because it
10:28
Speaker 1: is sort of like magic that we all feel as
10:30
Speaker 1: a kid, but it's so pervasive in our everyday lives.
10:34
Speaker 1: You know, like people listening to this podcast, they're not
10:38
Speaker 1: actually listening to our voice. They're listening to a little
10:42
Speaker 1: tiny magnet in their earphones or speakers making the sounds
10:45
Speaker 1: that we would make with our voices. Right, that's right,
10:48
Speaker 1: We're all just listening to magnets talking to us all day,
10:50
Speaker 1: following instructions from magnets. Right, magnets are basically in charge
10:54
Speaker 1: of our lives. Yeah, turn left at the upcoming intersection,
10:57
Speaker 1: says this magnet basically, right, It like it's so any
11:02
Speaker 1: any media, TV, movies, podcast you listen to, or your
11:06
Speaker 1: Alexa that you talked to, or any uh, all any
11:09
Speaker 1: of these things. Right, it's all bangnets, that's right. Yeah,
11:12
Speaker 1: there's a little magnet inside every speaker. It's a little
11:15
Speaker 1: electro magnet, and there's a really powerful and useful because
11:17
Speaker 1: they can be turned on and off using you know, circuitry.
11:21
Speaker 1: And so you're right. Magnets are everywhere and everyone also
11:24
Speaker 1: has a sort of a grasp of magnetism. Right, It's
11:26
Speaker 1: not like some weird thing out there in space. It's
11:29
Speaker 1: right here, it's in front of us. We can play
11:31
Speaker 1: with it. Everybody has experiences playing with magnets, um and
11:35
Speaker 1: so it's something that feels very tactile. All right, So
11:37
Speaker 1: today we'll talk about what is the strongest magnet? And
11:40
Speaker 1: so as usual, Daniel, you went out there and wondered
11:44
Speaker 1: if people knew what the strongest magnet in the universe was.
11:47
Speaker 1: That's right. And as usual with the Extreme Universe series,
11:50
Speaker 1: I really try and to get people to think universal.
11:53
Speaker 1: Don't just think about the Earth or a solar system,
11:55
Speaker 1: think about our place in the universe. And so you'll
11:58
Speaker 1: hear sometimes I prompted people a little bit to think
12:01
Speaker 1: about whether there are big space magnets out there. So
12:04
Speaker 1: think about yourself before you listen. Where do you think
12:07
Speaker 1: the strongest magnet in the universe is? Here's what people
12:10
Speaker 1: had to say. It's a black hole of the magnetic field.
12:13
Speaker 1: I feel like I should know the answer to these questions.
12:15
Speaker 1: I call the Earth. How about that? I would just
12:18
Speaker 1: say the gravitational pools stars. But I don't know what
12:21
Speaker 1: that means about gravitation and magnetism at least I don't know.
12:25
Speaker 1: I have no idea. I have no idea. Would it
12:30
Speaker 1: be Japan? I don't have any idea. The National High
12:34
Speaker 1: Magnetic Field Laboratory, Okay, And how do they make a
12:36
Speaker 1: really high magnetou? Uh to a combination of uh these
12:41
Speaker 1: bitter disc copper coils and super conducting coiled wires. And
12:47
Speaker 1: do you think the magnets here on Earth are stronger
12:48
Speaker 1: than anything else out there in the universe or their
12:50
Speaker 1: strongest stronger magnets out there in the universe. There should
12:53
Speaker 1: be stronger magnets out there in the universe, all right.
12:55
Speaker 1: Not a lot of bright ideas here. You didn't attract
12:58
Speaker 1: a lot of very um um creative answers a lot
13:02
Speaker 1: of people just said I have no idea. Yeah, a
13:04
Speaker 1: lot of people have no idea. Um. I like the
13:07
Speaker 1: ones said maybe the Japanese because they seem pretty clever.
13:10
Speaker 1: The last one is really my favorite because he really
13:12
Speaker 1: knew what he was talking about. And the fun bit
13:15
Speaker 1: is that after I was done interviewing him, he was like,
13:17
Speaker 1: what's this for? And then I described our podcast and
13:20
Speaker 1: he's like, oh my god, I love that podcast. I
13:22
Speaker 1: listened to it every week. You didn't realize that he
13:27
Speaker 1: was going to be on the podcast. It only sunk
13:29
Speaker 1: in afterwards. Just a random person who listened to this podcast.
13:33
Speaker 1: You interviewed him on the street, Yeah, exactly. So you
13:36
Speaker 1: can happen? Can happen? Yeah? Yeah, you might be a
13:39
Speaker 1: listener to this podcast and one day you might get
13:41
Speaker 1: asked by a random physicist. Have better chances if you're
13:45
Speaker 1: walking around in the afternoon at you see Irvine than
13:48
Speaker 1: if you are, you know, in Bangkok or something, But yeah,
13:51
Speaker 1: it could happen to you. Quantum mechanically, anything can happen.
13:54
Speaker 1: That's not true, that's a that's a comic book sign.
13:57
Speaker 1: That's right. Quantum mechanically, you can't go back in time. Yeah, well,
14:00
Speaker 1: I don't think I would ask to have a very
14:02
Speaker 1: creative answer or accurate as for either. I mean, I
14:05
Speaker 1: don't really know what is the strongest magnet in the universe,
14:09
Speaker 1: or where where you would find it, or how you
14:11
Speaker 1: would make it. And one of the fascinating things that
14:13
Speaker 1: there's lots of different ways to make magnets, right, You've
14:16
Speaker 1: got a permanent magnets, you've got electro magnets, you've got superconductors,
14:19
Speaker 1: you've got crazy stuff going on inside stars, and each
14:22
Speaker 1: of them have their own limitations for how strong you
14:25
Speaker 1: can get that magnet. So it really it turned out
14:27
Speaker 1: to be quite a rich topic. But um, I think
14:29
Speaker 1: we covered this in a little bit in our podcast before,
14:32
Speaker 1: is that all of these ways of making magnets, they're
14:35
Speaker 1: all sort of the same, aren't they. They're all based
14:37
Speaker 1: on kind of the same quantum mechanical properties of stuff.
14:42
Speaker 1: That's right. In the end, it all comes down to
14:44
Speaker 1: the same concept, which is moving charged particles. Because of
14:48
Speaker 1: this deep connection between electricity and magnetism. Anytime you move
14:53
Speaker 1: a charged particle, that's an electric current, and every current
14:56
Speaker 1: makes a magnet. And that's true of course for electromagnets,
14:59
Speaker 1: which will dig into. But sort of counterintuitively, it's also
15:02
Speaker 1: the reason you have that fridge magnets have a magnetic field,
15:05
Speaker 1: or any little permanent magnet, even if you don't see
15:07
Speaker 1: something moving, even if it doesn't have a current, it's
15:10
Speaker 1: all based on the same idea. Yeah, and it sort
15:14
Speaker 1: of does have a current because in the end, like
15:16
Speaker 1: a permanent magnet is a bunch of little magnets at
15:19
Speaker 1: all points in the same direction, and those little magnets
15:22
Speaker 1: and the magnetic field in the end comes from the
15:24
Speaker 1: quantum mechanical spin of that particle. So you have a
15:27
Speaker 1: particle with an electric charge on it, like an ionized
15:31
Speaker 1: atom inside that net magnet, like a piece of iron
15:34
Speaker 1: that doesn't have its charges all balanced, and it has
15:37
Speaker 1: quantum mechanical spin. And remember we talked about this on
15:40
Speaker 1: an episode. Quantum mechanical spin isn't actual spin. It's not
15:43
Speaker 1: like a thing is spinning like a top, but it's
15:47
Speaker 1: close enough to spin that the motion of it, the
15:50
Speaker 1: rotation of it, this quantum mechanical version of spin will
15:53
Speaker 1: also generate a magnetic field. So any charge particle that
15:57
Speaker 1: has quantum mechanical spin also has a magnet the field. Okay,
16:01
Speaker 1: so I think that's a good place to start. So
16:02
Speaker 1: let's start with just your average fridge magnet and how
16:06
Speaker 1: that works. And you're saying the average fridge magnet works
16:10
Speaker 1: because all of the little particles in the are act
16:13
Speaker 1: like little magnets themselves, exactly. And if you just like
16:16
Speaker 1: take a chunk of iron from the earth, um then
16:19
Speaker 1: you'll have a bunch of little magnets in it, but
16:21
Speaker 1: they all point in random directions. And that's why, like
16:23
Speaker 1: a random piece of of metal that you dig out
16:26
Speaker 1: of the ground is not necessarily a magnet yet, but
16:28
Speaker 1: it has the capacity to be an overall magnet. And
16:31
Speaker 1: what you have to do is get all those magnets
16:33
Speaker 1: pointing in the same direction. And so you can think
16:36
Speaker 1: of it like a billion tiny little magnets, but they're
16:39
Speaker 1: all in random directions, right, so they cancel each other out,
16:41
Speaker 1: or exactly, they cancel each other out, and so overall,
16:45
Speaker 1: this lump of iron is not a magnet. Now, what
16:47
Speaker 1: happens if you put that in a big magnetic field, Well,
16:50
Speaker 1: each of those little tiny magnets are gonna line up
16:53
Speaker 1: with the magnetic field, because that's what the magnetic field does.
16:56
Speaker 1: It turns magnets It's like looking at a compass, right,
16:59
Speaker 1: a compass lines up with the Earth's magnetic field. Each
17:02
Speaker 1: of these little iron atoms are a tiny little compass,
17:05
Speaker 1: and if you put them in a magnet, a strong one,
17:07
Speaker 1: they will line up with that magnetic field. And then
17:10
Speaker 1: you take the magnet away and they still are aligned.
17:13
Speaker 1: They can move around, you know, like, aren't they fixed
17:16
Speaker 1: in a crystal or in some molecule. They can still
17:19
Speaker 1: kind of reorient them those themselves. Yeah, they can still
17:22
Speaker 1: reirient themselves. You're right that they're sort of fixed in
17:24
Speaker 1: a crystal, but that affects like the spacing between them there.
17:27
Speaker 1: They still have freedom to rotate, right, It's not like
17:31
Speaker 1: tinker toys where you have where they're fixed by some
17:34
Speaker 1: rod to each other. There is a relationship there and
17:37
Speaker 1: it comes from a chemical bond. But they do have
17:39
Speaker 1: freedom to rotate still within that crystal. Do you mean
17:42
Speaker 1: when you say particles, you mean like the electrons or
17:44
Speaker 1: the protons, But what do you mean exactly inside of
17:47
Speaker 1: those magnet materials? Well, I think the best thing to
17:49
Speaker 1: do is to think about the whole iron atom, right,
17:52
Speaker 1: um as one, because that's where the magnetic field comes from.
17:55
Speaker 1: But in the end, it does come down to the
17:57
Speaker 1: little particles inside it. You know, this is the standard
18:00
Speaker 1: in physics is like shells. Right. You can think of
18:02
Speaker 1: the magnet as a whole. You can think of the
18:04
Speaker 1: atom irons is having little magnets on them, or you
18:07
Speaker 1: can think of the magnetic field of the atom of
18:10
Speaker 1: iron as being a sum of the magnetic fields of
18:13
Speaker 1: all the protons and the electrons. And that's actually why
18:16
Speaker 1: some kind of materials can be magnets, like iron. It's
18:20
Speaker 1: because the electric fields. It's because the magnetic field don't
18:23
Speaker 1: exactly cancel out right, whereas other materials where the electron
18:27
Speaker 1: shells are totally filled, that everything just balances and all
18:30
Speaker 1: the magnetic fields of the atom are canceled out. Oh man,
18:33
Speaker 1: you just blew my mind. Yeah. So in the end,
18:36
Speaker 1: all my life I've known about magnets, I've never known
18:39
Speaker 1: this piece of information. So that's why that's why iron
18:41
Speaker 1: is so special. That's why iron and other materials. Yeah,
18:44
Speaker 1: it's it's precisely because the alignment the electrons and whether
18:47
Speaker 1: the shells are filled. And the cool thing about magnets
18:50
Speaker 1: is that in the end they're quantum mechanical like magnets
18:53
Speaker 1: don't work. If quantum mechanics does, isn't real. So you're
18:55
Speaker 1: holding in your pocket a quantum matt You are listening
18:58
Speaker 1: right now to a quantum magnet. Well you are, and
19:01
Speaker 1: you're not because it's quantum. But you're both laughing and
19:04
Speaker 1: not laughing at these jokes. That's right. It's it's both
19:08
Speaker 1: good and that exactly. So either something special about iron,
19:14
Speaker 1: that basic configuration of it doesn't cancel out all the
19:17
Speaker 1: little magnets of its electrons and protons. Yeah, and you
19:21
Speaker 1: know there's something special. But every element don't feel bad,
19:23
Speaker 1: you know, um beryllium or hydrogen or whatever. And that's
19:27
Speaker 1: the thing that makes the elements different, right is Basically
19:30
Speaker 1: it's all about the arrangement of the electrons in the
19:32
Speaker 1: in those shells. That's what makes something shiny or not shiny,
19:36
Speaker 1: or active or not active, or you know, a metal
19:39
Speaker 1: or goopy at room temperature whatever. It's all down to
19:41
Speaker 1: how the electrons fill out their orbitals. It's incredible how
19:45
Speaker 1: rich a variety of stuff you can get, Like the
19:48
Speaker 1: elements are so different from each other just from how
19:50
Speaker 1: you arrange these same particles. You know, it's just another
19:53
Speaker 1: example of this this thing that blows my mind every day,
19:56
Speaker 1: that the most amazing things in the universe come from
19:59
Speaker 1: the arrangements of stuff, not from the stuff itself. Right,
20:02
Speaker 1: The same materials make iron as they as you used
20:04
Speaker 1: to make hydrogen or silken or whatever. But if you
20:08
Speaker 1: arrange them in a particular way with a certain amount
20:10
Speaker 1: of each one, then you get a magnet. Yeah, exactly.
20:13
Speaker 1: And iron is not the only one that can make magnet, right,
20:15
Speaker 1: other other things can be magnets as well. I guess
20:18
Speaker 1: one thing I've never understood is what exactly is a magnet?
20:22
Speaker 1: And you know, whether we're talking about one particle with
20:24
Speaker 1: a spin direction or whatever, or a fridge magnet, Like
20:28
Speaker 1: what is that? Like? Why does it get attracted to metal?
20:32
Speaker 1: Why does mental get attracted to it? Wow, that's a
20:34
Speaker 1: pretty deep question. What is a magnet? I think it's
20:37
Speaker 1: hard to start from that direction. What is a magnet?
20:39
Speaker 1: I think it's easier to sort of think about the
20:42
Speaker 1: history of the idea, which is like, well, we see
20:45
Speaker 1: this thing right in the end, physics is all about
20:48
Speaker 1: describing the things we see. So people discovered magnets, right, Clearly,
20:52
Speaker 1: magnets are real, right, It's a thing and so what
20:54
Speaker 1: we did is we developed a mathematical formulation that explains it. Like, Okay,
20:59
Speaker 1: they seem to work this way, and when they're further apart,
21:01
Speaker 1: the force is weaker. When they're closer, they're stronger. Only
21:04
Speaker 1: certain things seem to feel them, and they feel them
21:06
Speaker 1: in this circumstance, and you can make this force in
21:09
Speaker 1: that circumstance when you move particles around. Right. So that's
21:12
Speaker 1: what we have, is we have this description of the
21:14
Speaker 1: things we've seen, and we try to understand it and
21:16
Speaker 1: simplify it. So in other words, you you don't know, Well,
21:20
Speaker 1: it depends. Are you asking like why are there magnets?
21:23
Speaker 1: Like could you have a universe without magnets? You know? Well,
21:26
Speaker 1: I guess I'm asking, like, like I know about the
21:28
Speaker 1: electromagnetic force, right, if I have one electron, it repels
21:32
Speaker 1: another electron because we're both negative and they repel each other, right,
21:35
Speaker 1: Like that's the force. But then why where does this
21:40
Speaker 1: you know, where do fridge magnets? Okay? Like is it
21:43
Speaker 1: the is the electrons in my magnet attracted to or
21:47
Speaker 1: repelled by the you know, electrons in the fridge door?
21:50
Speaker 1: And what's what's going on there? Yeah? Well, you know, Um,
21:52
Speaker 1: the fascinating about magnetic fields is they have a north
21:55
Speaker 1: and a south. Right, they have this direction to them,
21:58
Speaker 1: and so the north attract the south, and the south
22:01
Speaker 1: attracts the north, and north repels the north right. And
22:04
Speaker 1: so in that way, they're very similar to charges, right,
22:07
Speaker 1: positive and positive repel each other, and positive negative attract
22:10
Speaker 1: each other. For charges. For magnetis it's similar. You have
22:13
Speaker 1: this north and the south. One of the really amazing
22:16
Speaker 1: things about magnetism that I want to cover on a
22:18
Speaker 1: whole other podcast, is that you can never have a
22:20
Speaker 1: north by itself. Right, Like for electricity, you can have
22:24
Speaker 1: a positive particle over here and it's all by itself,
22:26
Speaker 1: and over there you can have a negative particle it's
22:28
Speaker 1: all by itself. In magnetism, you have to have a
22:31
Speaker 1: north and the south together. There's no such thing as
22:34
Speaker 1: a single north or a single south. Need both. You
22:37
Speaker 1: need both. And nobody really understands why if you could
22:41
Speaker 1: find a single north we call that a magnetic monopole,
22:44
Speaker 1: then I would actually solve a whole lot of problems
22:47
Speaker 1: in physics. Nobody understands why we've never seen one bring
22:49
Speaker 1: it down from me. So one electron does it one
22:52
Speaker 1: electron have a magnetic field or is it just a
22:55
Speaker 1: negative charge. One electron has a magnetic field because it
22:58
Speaker 1: has a quantum spin, and so what it has it's
23:00
Speaker 1: a magnetic north and a magnetic south. Yeah, so it
23:03
Speaker 1: attracts other electrons and also repels of their electrons. How
23:07
Speaker 1: does that work? Yeah, it depends on their alignments of
23:09
Speaker 1: the fields. Right, So if the if the electron A,
23:12
Speaker 1: if it's north and south are in the same direction
23:14
Speaker 1: as electron B, then they'll repel each other. If if
23:17
Speaker 1: it flips over right so that the north and the
23:19
Speaker 1: south are then closer together, then they'll attract each other.
23:23
Speaker 1: It's just like if you take two magnets, right, two
23:25
Speaker 1: magnets can repel each other or attract each other just
23:27
Speaker 1: based on the orientation. If you ever try to like
23:29
Speaker 1: stack a bunch of magnets, you'll see this effect that
23:32
Speaker 1: you need to arrange them in a certain way so
23:34
Speaker 1: that they the north and the south are a line
23:36
Speaker 1: so they stick together, otherwise they'll repel each other. Wait,
23:39
Speaker 1: so you're saying that two electrons can attract each other
23:42
Speaker 1: if you change the quantum spin. Is that kind of
23:45
Speaker 1: the caveat It's it's not you're You're not just like
23:48
Speaker 1: flipping the electron over, you're changing the spin of it. Yeah,
23:51
Speaker 1: that's right, because what does it mean to flip an
23:53
Speaker 1: electron over? Right, It's like it's a point particle doesn't
23:55
Speaker 1: have a direction, but it's spin has a direction. And
23:57
Speaker 1: if you flip that spin, then they will make genetically
24:00
Speaker 1: attract each other. They'll still electrically repel each other, but
24:04
Speaker 1: there would be a small magnetic attraction if they're magnetic
24:07
Speaker 1: fields are pointed in different directions. Yes, all right, that
24:10
Speaker 1: blows my mind a little bit. But magnets are awesome, right,
24:13
Speaker 1: this is why kids said magnets an adults level. Could
24:16
Speaker 1: you're saying sort of like, maybe not think about it
24:17
Speaker 1: too much. She was like, let's look at them from
24:20
Speaker 1: what they do, which is a somehow there is when
24:23
Speaker 1: you want to put a lot of these things together,
24:25
Speaker 1: you get this thing that has a north and south
24:27
Speaker 1: and oh man, I never say don't think about it
24:30
Speaker 1: too much. I'm mr think about it too much. I'm
24:32
Speaker 1: professor to think about it too much. No, for sure,
24:34
Speaker 1: I love to talk about like why do we have
24:37
Speaker 1: magnets at all? Like could you have a universe without
24:39
Speaker 1: magnets and be fascinating. Would be a dark place because
24:42
Speaker 1: remember light is electro magnetism. Light is an electric field
24:45
Speaker 1: and a magnetic field in balance, slashing back and forth,
24:48
Speaker 1: the electric field creates a magnetic field which goes back
24:50
Speaker 1: to create an electric field. So without magnetism, you couldn't
24:54
Speaker 1: have light, right, and you can have lots of stuff.
24:56
Speaker 1: So universe without magnets would be a dark place, all right. Well,
25:00
Speaker 1: so that's kind of a general idea of magnets, right then, right,
25:03
Speaker 1: it's it's like the alignment of the spins of the
25:06
Speaker 1: particles inside of molecules like iron or atoms like iron
25:10
Speaker 1: that then add up to make magnets. That's right. And
25:13
Speaker 1: if you want to make the strongest magnet you can
25:16
Speaker 1: in that kind of setup, right, just with the quantum
25:19
Speaker 1: spin to the particles, then you need to find just
25:21
Speaker 1: the right chemicals, just the right elements to mix together
25:24
Speaker 1: so they have really strong magnets and add all add up.
25:28
Speaker 1: And so people have been doing this for a while
25:29
Speaker 1: and they found that, you know, for example, boron can
25:31
Speaker 1: make magnets and neodymium can make magnets, and so the
25:36
Speaker 1: strongest magnet we've ever built out of sort of a
25:38
Speaker 1: permanent magnet setup. Is this combination neodymium, iron and boron together,
25:44
Speaker 1: and that makes the magnetic field that's one and a
25:47
Speaker 1: half tesla. Is that per ounce or per cubic centimeter
25:51
Speaker 1: of magnet? What is that relative to? Right? And the
25:55
Speaker 1: unit tesla? That's magnetic field per volume. So it doesn't
25:59
Speaker 1: really matter how how big, how large physically the magnet
26:02
Speaker 1: is because the magnetic field sort of per space because
26:06
Speaker 1: you know, the more stuff you get than the more
26:07
Speaker 1: magnet you get. But then it's distributed. I see. So
26:10
Speaker 1: tesla is like a normalized quantity, you like, it doesn't
26:14
Speaker 1: matter what scale you're looking at it. Yeah, if you
26:16
Speaker 1: get to one tesla magnets and you put them together,
26:18
Speaker 1: you don't get a too tesla magnet. You get it
26:20
Speaker 1: twice as big one tesla magnet. Oh wait, so it
26:23
Speaker 1: is dependent on scale. Well, the strength of the field
26:25
Speaker 1: doesn't change. Right, you had a larger one tesla magnet.
26:28
Speaker 1: If you put to one tesla magnets together, you don't
26:31
Speaker 1: get a two tesla magnet. So there's something special about
26:34
Speaker 1: these materials neodymium, iron and boron, and especially about that
26:37
Speaker 1: combination that somehow aligns everything really well, so then you
26:42
Speaker 1: get a strong magnetic feel. What's going on? Yeah, I
26:44
Speaker 1: don't know. It's a lot of complicated chemistry, and I
26:47
Speaker 1: think it's also just been a lot of experimentation. You know.
26:50
Speaker 1: I'm not sure it's really that well understood. I think
26:52
Speaker 1: people are just like, let's add a little boron, let's
26:54
Speaker 1: add a little neodymium. Let's see what happens. You know,
26:58
Speaker 1: let's not think about it as much. I said, let's
27:01
Speaker 1: think about it. But it doesn't mean I mean necessarily
27:03
Speaker 1: know the answer. Um. But yeah, that's the magic combination,
27:10
Speaker 1: and that's what's set the world record so far on
27:13
Speaker 1: Earth for the strongest permanent magnet. You know the magnet
27:16
Speaker 1: it doesn't require any power input, and you know the
27:19
Speaker 1: magnetic field there. You might wonder, like, what where does
27:22
Speaker 1: this energy come from? For the magnetic field, It comes
27:24
Speaker 1: from the spinning of all these particles. All those tiny
27:27
Speaker 1: little particles inside there are zooming around or not actually
27:30
Speaker 1: zooming with like zooming with their like spin, making this
27:34
Speaker 1: magnetic field. It's sort of awesome. Things cannot have spin, right,
27:37
Speaker 1: some particles you can have zero spin um. Some particles
27:40
Speaker 1: kind of zero has been. The Higgs boson has zero spin.
27:43
Speaker 1: But all particles that that make matter so fermons. They're
27:47
Speaker 1: all half integer spin particles, which means they have to
27:50
Speaker 1: have positive or negative spin, so they can't have zero.
27:54
Speaker 1: Those are fridge magnets, and that's what makes your refrige
27:57
Speaker 1: so attractive. Next time you just callously put fridge magnet
28:00
Speaker 1: up on your fridge, think about the billions of tiny
28:03
Speaker 1: little particles that are basically holding onto the fridge for
28:06
Speaker 1: you just by spinning around. All right, let's get into
28:08
Speaker 1: electro magnets and the strongest magnets in the universe. But
28:12
Speaker 1: first let's take a quick break. Alright, we're talking about
28:28
Speaker 1: the strongest magnets in the universe, and we talked about
28:31
Speaker 1: fridge magnets. The strongest fridge magnets ever made by humans
28:34
Speaker 1: is about one point for Tesla, which is like electric car,
28:39
Speaker 1: and then point forward an electric car. No, it's not
28:43
Speaker 1: just about total misinformation, man, this is an educational podcast.
28:48
Speaker 1: It's about like it's pretty strong, right, because that's pretty strong, right,
28:53
Speaker 1: Yeah sure, yeah, Like like if you stuck them into
28:56
Speaker 1: two those together, you you probably couldn't with your bare
28:59
Speaker 1: hands break them apart. No, it's a very strong force, yeah,
29:02
Speaker 1: exactly one point for tesla is a very strong magnet.
29:05
Speaker 1: But that's about the most you can get out of
29:07
Speaker 1: a fridge magnet or or permanent magnet or any kind
29:09
Speaker 1: of ferro magnetic material. That's what it's called. And the
29:12
Speaker 1: other thing about fridge magnets and permanent magnets is that
29:14
Speaker 1: they're pretty permanent. Right, you build this magnet, it takes
29:17
Speaker 1: a lot of energy to like change the direction of
29:19
Speaker 1: all those particles, make it go in another direction, or
29:22
Speaker 1: to bounce it out or something. And sometimes you want
29:24
Speaker 1: a magnet that you can turn on and off right,
29:26
Speaker 1: or that you can flip the other direction, like you
29:28
Speaker 1: want to build an electric engine or a speaker or
29:31
Speaker 1: something like that. That's the other kind of magnets that
29:34
Speaker 1: we're going to talk about, which is electro magnets exactly.
29:37
Speaker 1: And these work on basically the same principle, which is
29:40
Speaker 1: moving charges generated a magnetic fields. And so instead of
29:44
Speaker 1: relying on the charges like spinning weirdly quantum mechanically to
29:47
Speaker 1: make tiny midlettle magnets, you just take those particles and
29:50
Speaker 1: you move them along, like take a battery and drag
29:53
Speaker 1: a bunch of electrons through a wire. What happens you
29:56
Speaker 1: get a magnetic field that goes around the wire, makes
29:59
Speaker 1: these circular magnetic fields around the wire, and that's happening
30:02
Speaker 1: all the time. Like every electrical wire in your house,
30:06
Speaker 1: you know that's that's on it has a current through.
30:08
Speaker 1: If there's a magnetic field there, and you can see this,
30:11
Speaker 1: you just like turn on two wires near each other
30:13
Speaker 1: and you'll see them like jump towards each other or
30:15
Speaker 1: away from each other because of the magnetic fields. And
30:17
Speaker 1: so then the idea is that you and you can
30:19
Speaker 1: build those up. You know, that's why motors have coils, right,
30:23
Speaker 1: and electromagnets. You wind up the wire and each time
30:28
Speaker 1: you wind it up, you're sort of building and building
30:30
Speaker 1: the magnetic field onto itself. Yeah, So holding your mind
30:33
Speaker 1: the image of a wire and then draw around it
30:36
Speaker 1: sort of a circle has an arrow, and that's the
30:39
Speaker 1: direction of the magnetic field. Now, if you bend the
30:41
Speaker 1: wire to a circle, then you notice that those circular
30:44
Speaker 1: magnetic fields are all pointing in the same direction at
30:48
Speaker 1: the center of that circle. If you make a wire,
30:51
Speaker 1: you put it into a circle, and the magnetic fields
30:53
Speaker 1: around that wire all adds up to push in the
30:56
Speaker 1: same direction at the center of the circle, and so
30:58
Speaker 1: that's where you get the strong is magnetic field, like
31:01
Speaker 1: you focus it. It's like focusing the magnetic field by
31:04
Speaker 1: putting in in the loop. Yeah, it's like it's adding
31:07
Speaker 1: them all up constructively and you're not changing their directions.
31:10
Speaker 1: You're just getting them all to push in the same
31:12
Speaker 1: direction at once. So if you're, for example, if you're
31:14
Speaker 1: a magnet in the center of a loop of wire,
31:17
Speaker 1: then you're feeling the magnetic field from all the electrons
31:19
Speaker 1: all the way around that loop, all at the same time, right,
31:23
Speaker 1: And so that's where the strongest, the strongest field is
31:25
Speaker 1: there in the center. And you want it stronger, add
31:27
Speaker 1: another loop. You want it stronger, add another loop. And
31:30
Speaker 1: that's why electromagnets have all those coils, because every coil
31:34
Speaker 1: means more current. It just adds more magnetic field. Yeah.
31:36
Speaker 1: Like if you open up a motor, electric motor or
31:39
Speaker 1: a speaker, you'll see like the little copper lines just
31:42
Speaker 1: going around and around and around. That's the electromagnet. That's
31:45
Speaker 1: the electromagnet. And the really cool thing is turn off
31:48
Speaker 1: the current. Boom magnet goes away reverse the current magnet
31:52
Speaker 1: points the other direction, right, And that's why you can
31:56
Speaker 1: use electromagnets to control, for example, the vibrations of the
32:00
Speaker 1: surface of a speaker. That's how that's how we make
32:03
Speaker 1: a speaker make make sound, right, is that it turned
32:06
Speaker 1: on and off the electromagnet really fast, and it shakes
32:09
Speaker 1: the surface of the speaker, and that's what makes the
32:11
Speaker 1: sound that you hear. Yeah, it's amazing, it is really amazing. Yeah,
32:14
Speaker 1: And it also works the opposite direction. Right. If you
32:17
Speaker 1: just take a magnet and you move it through a
32:19
Speaker 1: coil of wire, what happens, Well, you get an electric field,
32:24
Speaker 1: So you get an electric current through the coil, and
32:26
Speaker 1: that's what a generator is, all right. So then that's
32:28
Speaker 1: how you make kind of an artificial electromantic field, right,
32:32
Speaker 1: not like a fridge magnet. Yeah, but what's what's artificial
32:36
Speaker 1: about it? It's it's still nature, it's still physics, it's
32:39
Speaker 1: still real. Yeah, but you have to put the electro
32:41
Speaker 1: in front of it for a reason, that's true. But
32:43
Speaker 1: just a magnet it makes it sound like the way
32:46
Speaker 1: you say, it makes it sound like I have like
32:47
Speaker 1: a weird after taste or something like you know. So
32:49
Speaker 1: then that's an electromagnet. And so this is where we
32:52
Speaker 1: can now get into really big magnets, right, Like we
32:55
Speaker 1: can go way past naturally metallic magnets with electromagnets, that's right.
33:00
Speaker 1: And the thing about this is that it requires um
33:03
Speaker 1: continuous source of power. Right. You can't just build a
33:06
Speaker 1: electro magnet and then walk away from it. You have
33:08
Speaker 1: to keep powering and when you stop powering it, it
33:10
Speaker 1: turns off. But these magnets can get really strong. In fact,
33:14
Speaker 1: the best way to make them even stronger is you
33:17
Speaker 1: make a coil of wire like we talked about before,
33:19
Speaker 1: but then you put a permanent magnet in the middle
33:22
Speaker 1: of it, and the to sort of add in this
33:24
Speaker 1: resonant way to make you an even stronger magnet, like
33:28
Speaker 1: a magnet on steroid. It's a magnet on magnet interaction
33:34
Speaker 1: that makes this lines up all the little magnetic domains
33:37
Speaker 1: and they enhance each other and so you get this.
33:39
Speaker 1: It's called a resistive magnet um a resistive electro magnet,
33:43
Speaker 1: and those can get really powerful. How powerful? So what's
33:47
Speaker 1: the strong is steroidal magnet that we've made on Earth?
33:51
Speaker 1: So it's this awesome project and Florida State and they
33:54
Speaker 1: call it Project eleven. I think it's named after the
33:57
Speaker 1: spinal tap thing like this magnet goes to eleven um
34:01
Speaker 1: and really not after the Stranger Things character. No, No,
34:05
Speaker 1: I think it's Ah. These guys are a little older
34:07
Speaker 1: than that, so I think their references are probably dated. Um.
34:11
Speaker 1: But their magnets goes up to just over forty one tesla. Wow.
34:16
Speaker 1: Yeah that's a lot, because it's it's like forty times
34:20
Speaker 1: the strongest metallic magnet, right, which you couldn't even separate
34:23
Speaker 1: with your hands. Yeah, thirty or so times. And they
34:26
Speaker 1: use this particular configuration. They actually don't use wire. They
34:29
Speaker 1: use these helical plates because it spreads out the energy
34:33
Speaker 1: a little bit more so it prevents it from overheating.
34:35
Speaker 1: It's invented by a guy named Bitter. His last name
34:38
Speaker 1: is Bitter b I T T e R. And so
34:40
Speaker 1: it's called a bitter magnet. Now I wouldn't I don't
34:42
Speaker 1: know what it tastes like, and I don't know how
34:45
Speaker 1: their competitors feel. But it's a bitter victory um and
34:48
Speaker 1: they have the strongest magnet. Wow. This might be a
34:51
Speaker 1: case where maybe naming it after yourself is maybe not
34:54
Speaker 1: the best idea, what if you should have picked your
34:56
Speaker 1: first name, you know, the John magnet, or what if
34:59
Speaker 1: your last n magnet is grumpy or something, you know,
35:02
Speaker 1: the grumpy principle, the grumpy theorem, or what if your
35:05
Speaker 1: name is like Magnets, it's the Magnets magnet that would admit, awesome,
35:09
Speaker 1: the magnetis magnet on Earth. So so then you can
35:12
Speaker 1: get up to forty one test load. That's as far
35:14
Speaker 1: as they've gotten so far. Yeah, and the thing that
35:17
Speaker 1: really limits them is that there's a huge amount of
35:19
Speaker 1: energy this all this current going through it, and basically
35:21
Speaker 1: this thing will just melt itself. And so the thing
35:24
Speaker 1: that keeps them from going higher up is that thing
35:26
Speaker 1: just gets too hot. And so the current effort these
35:29
Speaker 1: days is like how to get the heat out of there.
35:32
Speaker 1: And they have like water cooling and they have these
35:34
Speaker 1: air baffles, and you know, it's just a huge source
35:37
Speaker 1: of energy. They're pupping so much juice into this magnet,
35:40
Speaker 1: so much current that it literally like melts down. It's
35:44
Speaker 1: hard to keep it from blowing up exactly because all
35:47
Speaker 1: this wire is carrying this current and all wires have
35:50
Speaker 1: some resistance, right, and anytime you pump a current through
35:54
Speaker 1: a wire that has some resistance, it's going to heat up.
35:56
Speaker 1: That's what the resistance is. And so if you're generating
35:59
Speaker 1: a huge current is to make huge magnets, You're gonna
36:01
Speaker 1: get a huge amount of heat and eventually the thing
36:03
Speaker 1: will just melt down. So that's what they're working on,
36:05
Speaker 1: is to try to cool it off. And that actually
36:07
Speaker 1: leads us to the next kind of magnet, which tries
36:10
Speaker 1: to limit the resistance. If you can reduce the resistance
36:13
Speaker 1: of the wires, then you can pump more current through exactly.
36:16
Speaker 1: And so some people like for example, at the large
36:19
Speaker 1: hage On collider, we need really strong magnets to bend
36:21
Speaker 1: the particles going in a circle, because remember, particles that
36:24
Speaker 1: have charges will feel a magnetic force, they'll get bent.
36:28
Speaker 1: And so the way we make particles move in a
36:29
Speaker 1: circle the particle colliders is we have these really strong
36:32
Speaker 1: magnets and we use superconducting magnets. And the way that
36:35
Speaker 1: works is basically the same as any other electromagnet, except
36:38
Speaker 1: you use superconducting wire, which means this is much less resistance,
36:43
Speaker 1: so as much less heat lost and you get more current.
36:46
Speaker 1: And a huge current means big magnet so you basically, um,
36:49
Speaker 1: I mean, when you have a superconductor, we talked about
36:51
Speaker 1: this in a podcast, you basically have zero resistance, right,
36:54
Speaker 1: almost zero, yeah, exactly. Almost take a free wire kind
36:59
Speaker 1: of like as much current as you want, exactly, and
37:02
Speaker 1: the current just flies through with almost no resistance. And
37:04
Speaker 1: so most of the energy is then just going to
37:07
Speaker 1: the magnet and it's not heating the thing up, it's
37:09
Speaker 1: not gonna make it melt down. So then what's the
37:10
Speaker 1: strongest magnet we can make with that? Well, there's a
37:14
Speaker 1: group in the U. S. It's the National Magnetic Field Laboratory,
37:17
Speaker 1: and they've made it thirty two tesla magnet. And you
37:20
Speaker 1: might think, why isn't that stronger than the resistive magnet, right?
37:23
Speaker 1: And the reason is that, you know, you can do
37:25
Speaker 1: super conductivity. But we have the whole episode about how
37:28
Speaker 1: it works. It's a little bit delicate. It requires the
37:30
Speaker 1: electrons to move in pairs, etcetera. And if you have
37:33
Speaker 1: too strong a magnetic fields, it interferes with the super conductivity.
37:37
Speaker 1: So like, you can use super conjectivity to make a
37:39
Speaker 1: really strong magnet, but if you do, if you make
37:42
Speaker 1: it strong enough, it'll ruin the super conductivity of your wires. Oh,
37:46
Speaker 1: I see, it's like you made it too good that
37:48
Speaker 1: it just breaks down the laws of physics. Nothing breaks
37:52
Speaker 1: the laws of physics, man, But it make it a
37:56
Speaker 1: super conductive yeah, exactly, it ruins the super context by uh.
38:00
Speaker 1: And but so that goes up to thirty two tesla
38:02
Speaker 1: and that's pretty powerful. But then you're saying that you
38:05
Speaker 1: can combine all these things to get like an ub omega,
38:09
Speaker 1: like a voltron type of magnet. Yeah, exactly. As usual,
38:12
Speaker 1: the best way to do something in physics is to
38:14
Speaker 1: like combine all the other best ideas and see what
38:17
Speaker 1: you get. And so some folks made a bitter magnet, right,
38:20
Speaker 1: that's this thing with a helical plates so that they
38:24
Speaker 1: do you distribute the heat and the current, etcetera. And
38:27
Speaker 1: then they added super conducting wires to that. So there's
38:29
Speaker 1: a combination bitter resistive magnet and the super and super
38:33
Speaker 1: conducting wires, and they got up to forty five tesla.
38:36
Speaker 1: And that's again at the Florida State University Magnet Lab.
38:39
Speaker 1: So they're the current reigning champions through the most magnetic
38:43
Speaker 1: that's right, the most attractive and repulsive lab in the
38:46
Speaker 1: history of the attract the best students, right, But these
38:50
Speaker 1: are all magnets that are sort of sustained. Right. You
38:52
Speaker 1: can turn this magnet and you can keep it going
38:54
Speaker 1: for a little while until it overheats. These are the
38:57
Speaker 1: magnets that are sustained. If you want to to generate
39:00
Speaker 1: like really strong magnetic fields, you can do it in
39:03
Speaker 1: a way that is not sustainable. Okay, you can do
39:05
Speaker 1: it like a momentary, like a like blow it all
39:09
Speaker 1: up in one magnetic movement. Yeah, you can get really
39:13
Speaker 1: brief strong magnetic pulses basically, And the way they do
39:16
Speaker 1: this is they use explosives and it compresses the magnetic
39:20
Speaker 1: field inside the electromagnet as you as you pulse it,
39:23
Speaker 1: so you turn on the electromatic you like surrounded with
39:26
Speaker 1: bombs basically, and it compresses the whole magnet so that
39:29
Speaker 1: very briefly, for like a few microseconds, you have a
39:32
Speaker 1: magnet that's up to like thousands of tesla. So it's
39:36
Speaker 1: so if I if I squeeze a magnet, it makes
39:38
Speaker 1: it more magnetic, yes, because remember that the unit tesla
39:42
Speaker 1: is per volume. So if you can get the same
39:45
Speaker 1: magnetic stuff into a smaller space, then the magnetic field
39:48
Speaker 1: is basically higher, so they use explosives to compress it
39:52
Speaker 1: to briefly get a super magnet. So for a few
39:55
Speaker 1: microseconds you can have a magnet that's like a couple
39:58
Speaker 1: of thousand tesla. Yeah, exactly, And that's not something you
40:01
Speaker 1: can sustain because obviously you're blowing up the magnet as
40:04
Speaker 1: you're making it. It's just sort of like, you know,
40:07
Speaker 1: at the point of principle, can we do this? Uh,
40:09
Speaker 1: some people are doing these kind of explosive magnet experiments.
40:12
Speaker 1: That's terrible for a cell phone reception, exactly. It's also
40:15
Speaker 1: not great for your speaker in your iPhone, all right,
40:17
Speaker 1: So so that those are all sort of man made magnets,
40:20
Speaker 1: right like here on Earth with human engineering, you're saying,
40:24
Speaker 1: the most we can get to sustain is a couple
40:28
Speaker 1: of dozen tesla, and in microseconds, the most we can
40:32
Speaker 1: get to a couple of thousand tesla. That's right. That's
40:34
Speaker 1: like the peak of human magnetic achievement. That's right, exactly.
40:38
Speaker 1: So far that's the most magnetic we've gotten. But then
40:42
Speaker 1: we can get out, go out into space, and then
40:44
Speaker 1: things get crazier, right, that's basically always true. Go out
40:48
Speaker 1: in the space things get crazy, all right, Well let's
40:53
Speaker 1: get crazy, Daniel. But first let's take a quick break.
41:08
Speaker 1: All right, so we covered human magnets, meaning magnets we
41:12
Speaker 1: can make, or magnetic moments and magnime of your brain. Right,
41:15
Speaker 1: that's also human magnets, right right, and superheroic magnets, all
41:20
Speaker 1: that in our imaginations. But now now things get crazy
41:25
Speaker 1: when you go off into space because you can have
41:27
Speaker 1: crazy magnets out there, that's right. And uh, you know,
41:30
Speaker 1: let's remind ourselves, like the Earth has a magnetic field,
41:33
Speaker 1: and that magnetic field we think comes from like things
41:36
Speaker 1: sloshing around inside the Earth. Basically again, you know charged currents, right,
41:41
Speaker 1: these currents of sort of like charged ionized rock slashing
41:44
Speaker 1: around the magnet inside the Earth is somehow making a
41:47
Speaker 1: magnetic field. But that's only like thirty or sixty micro tesla.
41:51
Speaker 1: And if you go out, you leave the Earth, right then.
41:54
Speaker 1: The Moon doesn't have a very strong magnetic field, but
41:56
Speaker 1: the Sun does. The Sun's magnetic field can be much
41:59
Speaker 1: stronger than the Earth, but even that is not that strong.
42:02
Speaker 1: Like when you get a sun spot, you know, something
42:04
Speaker 1: really concentrated bit of magnetism. It gets up to like
42:07
Speaker 1: point one tesla, so the real which is a lot
42:11
Speaker 1: more than the Earth's magnetic field, but it's not you know,
42:14
Speaker 1: it's not stronger than a m than the magnets we
42:17
Speaker 1: can make in the lab here on Earth. So we
42:19
Speaker 1: have the strongest magnets in the Solar system here on Earth,
42:22
Speaker 1: well that we know of, that we know of. Yeah,
42:24
Speaker 1: that's true. Um, that we've you know, we've flown here
42:27
Speaker 1: in the Sun. We're the chap that's right. We are
42:30
Speaker 1: more powerful than the Sun. Man, that's pretty impressive. But
42:33
Speaker 1: I thought sun spots could you know, like wipe out
42:35
Speaker 1: communications and stuff like that. Yeah, they can, but that's
42:38
Speaker 1: mostly because of the flux of charged particles. It's basically
42:41
Speaker 1: like throws a huge number of protons at the Earth
42:44
Speaker 1: and that can wipe out your electronics. It's not the
42:47
Speaker 1: magnetic field. It's like it's the throwing stuff at us. Yeah, exactly,
42:50
Speaker 1: it's basically shooting us with tiny bullets. Um and right,
42:53
Speaker 1: And that's bad. Um, But you know, not just in
42:56
Speaker 1: our solar system and that you were talking about the
42:59
Speaker 1: universe right then, are very powerful magnetic fields. And we
43:02
Speaker 1: talked about for example, weird kinds of stars and neutron stars,
43:06
Speaker 1: this really strange kind of star you get sometimes after
43:09
Speaker 1: the collapse of a star, and a star burns and
43:11
Speaker 1: it uses the most of its fuel, and then gravity
43:14
Speaker 1: that takes over, because when it stars burning, it's exploding
43:16
Speaker 1: and that's keeping it from getting too dense. But once
43:19
Speaker 1: it stops burning, then gravity just takes over and it
43:22
Speaker 1: squeezes it down harder and harder, and eventually you can
43:25
Speaker 1: get a star where the pressure is so great that
43:27
Speaker 1: everything becomes a neutron essentially, And then you get this
43:30
Speaker 1: neutron star, and for reasons we don't understand, because we
43:33
Speaker 1: don't know how what's going on inside it and what's
43:36
Speaker 1: slashing around. The magnetic fields there can be enormous, really, yeah,
43:40
Speaker 1: they can be up to a million a million tesla. Okay, wait,
43:43
Speaker 1: so it's a neutron star. So it's a it's a
43:45
Speaker 1: whole bunch of neutrons squished together. And so my first
43:49
Speaker 1: question is why is it even generating a field? Isn't
43:52
Speaker 1: it all neutral? Yeah, it's all neutral, right, But remember
43:55
Speaker 1: neutrons are made of quarks, and quarks do have charges,
43:59
Speaker 1: and so quarks have little magnetic fields, and so something
44:02
Speaker 1: about that. You know, how the quarks are slashing around,
44:05
Speaker 1: and what's going on with the neutrons is generating a
44:07
Speaker 1: magnetic field. But again, we don't really understand it very well.
44:10
Speaker 1: It's sort of a mystery. A million tesla, So how
44:12
Speaker 1: do we even know this number? How did we know? How?
44:15
Speaker 1: How can we measure the magnetic field from back here
44:19
Speaker 1: of a neutron star out there? Yeah, that's a great question.
44:21
Speaker 1: It's not like we're throwing fridge magnets out there right,
44:25
Speaker 1: are in fillings spreading it around? That would be awesome.
44:30
Speaker 1: Uh No, As usual in astronomy, you can't usually construct experiments.
44:33
Speaker 1: You just have to observe them, right, And so what
44:36
Speaker 1: you do is you look at the motion of particles
44:38
Speaker 1: near these things. You look at like ionized gas, How
44:42
Speaker 1: is it getting moved? You know, if it's flowing in
44:44
Speaker 1: this direction? And then it turns you can measure the
44:46
Speaker 1: magnetic field basically by the flows of gas nearby these
44:49
Speaker 1: objects and and other particles. Yeah, and then you say, like,
44:53
Speaker 1: how strong does the magnetic field have to be? So
44:55
Speaker 1: that explains what we're looking at. So you can look
44:57
Speaker 1: at it and say that's a million tesla magnet right there, Yeah, exactly,
45:02
Speaker 1: And you know, some of these stars get even super weird,
45:05
Speaker 1: right like, and we don't understand it, but some neutron
45:08
Speaker 1: stars get into this really strange state that they're called
45:10
Speaker 1: a magnetar. And of course they're called a magnetar, not
45:14
Speaker 1: just because that's a super weird, awesome name and kudos
45:17
Speaker 1: to whoever came up with it. Um, And it sounds
45:19
Speaker 1: like the kind of sword you might yield in some
45:21
Speaker 1: weird science fiction to still be in universe. But because
45:24
Speaker 1: they has like Manet or something, it sounds like Magneto's car. Yeah,
45:31
Speaker 1: there you go, Hey, pull up the magnetar. I gotta
45:33
Speaker 1: go out for dinner. Yeah, I gotta go pick up Yeah, exactly,
45:39
Speaker 1: we're gonna go. We got some things to talk about. Um.
45:42
Speaker 1: And these things are crazy. I mean these are ten
45:45
Speaker 1: to the eleven tesla, right, so remember, like the sun
45:48
Speaker 1: is less than a tesla, a neutron star is a
45:50
Speaker 1: million tesla. These things are almost a million, a billion,
45:55
Speaker 1: almost a trillion tesla. Wow, ten thousand million Tesla's ten
46:01
Speaker 1: almost ten million million, right, ten to the twelve is
46:04
Speaker 1: ten to the five. It's ten thousand is how you said? Sorry,
46:09
Speaker 1: hundred thousand million people with pH ds Welcome for a
46:13
Speaker 1: podcast two simple maths Learning to count to eleven with
46:17
Speaker 1: Daniel and Horge. This one goes to eleven. Daniel Horge
46:22
Speaker 1: explains simple counting. Yeah, but these things are insane, right, Like,
46:26
Speaker 1: what is it like to be there? Like it would
46:27
Speaker 1: shred you, you know, the powerful the forces there are
46:29
Speaker 1: so powerful. We don't even really understand what would happen.
46:33
Speaker 1: Would you feel it? Like if I was next to
46:34
Speaker 1: a magnetar, would I feel attracted or shredded by it?
46:37
Speaker 1: Because I'm pretty mutual, not just politically but in terms
46:42
Speaker 1: of magneticness. Right, Well, I think you're relies on electrical
46:47
Speaker 1: currents to control itself, and your brain does so it
46:50
Speaker 1: would definitely have an effect on all the charged particles
46:52
Speaker 1: in your brain and all the currents that are happening
46:54
Speaker 1: in your body, and so you couldn't think. You couldn't
46:57
Speaker 1: think it might even like rip all the iron out
47:00
Speaker 1: of your blood cells, which doesn't sound good, not really recommended,
47:05
Speaker 1: which has happened in comic books with Magneto, by the way,
47:08
Speaker 1: Is that right alright? The comic writers have thought about that.
47:10
Speaker 1: Magneto is a physics inspired comic hero. That's why I
47:13
Speaker 1: like him. So much. I mean he's a bad guy,
47:16
Speaker 1: all right, you know, but yeah, he's in the in
47:17
Speaker 1: the recent movies, he turns around, he helps the X
47:19
Speaker 1: Men a little bit, so you know, I know he's um,
47:23
Speaker 1: he's not a bad guy. They kind of put him
47:25
Speaker 1: as he's like the Malcolm X two xaviors Marthon Luther King. Oh,
47:30
Speaker 1: I say, he's just got a more complicated arc. He's
47:32
Speaker 1: not clearly good or bad. Yeah, he's just he's just
47:34
Speaker 1: a different philosophy. Killed the humans, that's his philosophy. Yeah,
47:38
Speaker 1: basically he's just misunderstood that. Say what you want about
47:42
Speaker 1: the tenets of Magneto. At least it's a at least
47:45
Speaker 1: it's an ethos and he has a cool power, all right.
47:47
Speaker 1: So would you say then that's the strongest magnet in
47:50
Speaker 1: the universe a magnetar, which is a weird inexplicable neutron star. Yeah,
47:55
Speaker 1: that's the strongest magnet we're aware of in the universe.
47:58
Speaker 1: And you know there are other strong magnets like um.
48:00
Speaker 1: Black holes can also have magnets around them, like these blazers,
48:03
Speaker 1: these jets of particles that are aligned to go perpendicular
48:07
Speaker 1: from the plane of a galaxy. We think there's some
48:08
Speaker 1: sort of magnetic thing happening there. We don't really know
48:11
Speaker 1: how strong it is, but there are really really powerful
48:14
Speaker 1: magnetic magnetic fields out there in the universe that would
48:17
Speaker 1: just shredd you to bids and if you're near it,
48:20
Speaker 1: that's right, and it would tear all the magnets off
48:22
Speaker 1: your fridge. So if you have like some really complicated
48:24
Speaker 1: like freeze scrabble game going on in the take a picture.
48:28
Speaker 1: Take a picture, and don't bring it when you go
48:30
Speaker 1: visit the magnetar. In fact, don't bring your fridge at all,
48:33
Speaker 1: you know, because you're not coming back. How are you
48:35
Speaker 1: gonna have cold drinks? Man? You can't travel through space
48:37
Speaker 1: with that cold drinks? All right? So we got to
48:41
Speaker 1: our answer. That's the strongest magnet in the new universe
48:45
Speaker 1: that we know about. That's right. Once again, the universe
48:48
Speaker 1: dwarfs what's happening here on Earth. We have all these
48:51
Speaker 1: people spending millions of dollars to make really powerful magnets,
48:54
Speaker 1: but their orders of magnitude weaker than what's happening out
48:58
Speaker 1: there in neutron stars and magnetar. So we have a
49:01
Speaker 1: ways to go, people. But I think it's cool to
49:03
Speaker 1: remember that there are magnets everywhere. You know, you're listening
49:06
Speaker 1: to us through magnets, and the idea that you every
49:10
Speaker 1: your body has a magnetic field and your brain is
49:13
Speaker 1: generating and electromagnetic field. Just thinking about and processing the
49:17
Speaker 1: words that you're listening right now. That's right. Your whole
49:21
Speaker 1: nervous system runs on electromagnetic fields, so you basically are
49:24
Speaker 1: a magnet. You, dear listener, are very magnetic and attractive.
49:30
Speaker 1: All right, thanks for joining us. Hope you enjoyed dad.
49:32
Speaker 1: We'll see you guys next time. If you still have
49:42
Speaker 1: a question after listening to all these explanations, please drop
49:45
Speaker 1: us a line. We'd love to hear from you. You
49:47
Speaker 1: can find us at Facebook, Twitter, and Instagram at Daniel
49:51
Speaker 1: and Jorge that's one word, or email us at Feedback
49:54
Speaker 1: at Daniel and Jorge dot com. Thanks for listening, and
49:58
Speaker 1: remember that Daniel and Jorge Explained Universe is a production
50:01
Speaker 1: of I Heart Radio. More podcast from my Heart Radio
50:05
Speaker 1: visit the I Heart Radio app, Apple Podcasts, or wherever
50:08
Speaker 1: you listen to your favorite shows. H