1
00:00:08,400 --> 00:00:11,559
Speaker 1: I love that science has made so much progress in

2
00:00:11,600 --> 00:00:16,360
Speaker 1: explaining the universe, unraveling its inner workings. It's almost incredible

3
00:00:16,480 --> 00:00:20,720
Speaker 1: what we've accomplished. There's almost nothing left in our everyday

4
00:00:20,720 --> 00:00:24,760
Speaker 1: lives that remains a true deep mystery. Sure, the early

5
00:00:24,840 --> 00:00:27,960
Speaker 1: universe and the black holes and lots of extreme situations

6
00:00:28,000 --> 00:00:31,280
Speaker 1: still defy explanation, and we dig into those on the

7
00:00:31,280 --> 00:00:35,919
Speaker 1: podcast all the time, But your everyday experience is mostly

8
00:00:36,000 --> 00:00:39,520
Speaker 1: explained and understood. The motion of the stars, the Sun,

9
00:00:39,640 --> 00:00:42,800
Speaker 1: the planets, those are understood. We know what an earthquake

10
00:00:42,920 --> 00:00:45,240
Speaker 1: is and how weather works, even if we can't predict

11
00:00:45,240 --> 00:00:48,519
Speaker 1: them very well. Makes me wonder what it was like

12
00:00:48,720 --> 00:00:52,199
Speaker 1: to be a human when there were unexplained mysteries right

13
00:00:52,280 --> 00:00:55,480
Speaker 1: up in your face every day, when science hadn't fully

14
00:00:55,520 --> 00:00:58,600
Speaker 1: conquered magic. Today, we're going to try to get the

15
00:00:58,600 --> 00:01:02,040
Speaker 1: flavor of that by talking about the remaining mysteries of

16
00:01:02,040 --> 00:01:06,880
Speaker 1: one of the most magical forces in physics, magnetism. Welcome

17
00:01:07,000 --> 00:01:10,600
Speaker 1: to Daniel and Kelly's Extraordinarily Magnetic Universe.

18
00:01:23,880 --> 00:01:28,440
Speaker 2: Hello, I'm Kelly Windersmith. I study parasites and space and magnets. Man,

19
00:01:28,520 --> 00:01:32,000
Speaker 2: how do they work? What a miracle magnets are Hi.

20
00:01:32,160 --> 00:01:35,560
Speaker 1: I'm Daniel. I'm a particle physicist and my job is

21
00:01:35,640 --> 00:01:39,240
Speaker 1: to unravel how the world works. And yet I sort

22
00:01:39,280 --> 00:01:41,400
Speaker 1: of sometimes wish there really was magic.

23
00:01:41,640 --> 00:01:43,520
Speaker 2: Yeah, yeah, no, me too. That would be pretty cool.

24
00:01:43,520 --> 00:01:45,320
Speaker 2: Like it's been really fun being a parent and seeing

25
00:01:45,319 --> 00:01:47,480
Speaker 2: the like sort of magical world that resides in my

26
00:01:47,560 --> 00:01:50,080
Speaker 2: daughter's head and kind of wishing some of it could

27
00:01:50,120 --> 00:01:52,640
Speaker 2: be real. But you know what exists in the real

28
00:01:52,680 --> 00:01:54,680
Speaker 2: world is the Insane Clown Posse.

29
00:01:56,080 --> 00:01:59,840
Speaker 1: And are you saying they're magicians.

30
00:02:00,520 --> 00:02:04,720
Speaker 2: No, I think they're into magic. So they the Insane

31
00:02:05,280 --> 00:02:08,720
Speaker 2: ICP is from Detroit, and I grew up in Toledo,

32
00:02:08,960 --> 00:02:12,480
Speaker 2: and so the Insane Clown Posse often had shows in Toledo,

33
00:02:12,520 --> 00:02:15,400
Speaker 2: and I got sort of exposed to some of their music,

34
00:02:15,560 --> 00:02:19,360
Speaker 2: and exposed is maybe exposed. You know, I feel uncomfortable

35
00:02:19,360 --> 00:02:21,000
Speaker 2: when I hear the word exposed, and that's how I

36
00:02:21,000 --> 00:02:23,640
Speaker 2: felt when I listened to ICP. But they had this

37
00:02:23,680 --> 00:02:26,400
Speaker 2: one song, and anytime I hear about magnets, I think

38
00:02:26,400 --> 00:02:29,440
Speaker 2: about this one song they had called Miracles, where this

39
00:02:29,560 --> 00:02:31,240
Speaker 2: is a kid show, so I'm going to replace a

40
00:02:31,240 --> 00:02:34,800
Speaker 2: word with stinkin'. They'd be like stinking magnets. How do

41
00:02:34,880 --> 00:02:37,840
Speaker 2: they work? And I was like, I think if you

42
00:02:37,919 --> 00:02:41,040
Speaker 2: talk to someone, we could tell you there's probably an answer.

43
00:02:41,160 --> 00:02:43,960
Speaker 2: It doesn't have to be a miracle. But they do

44
00:02:44,040 --> 00:02:46,240
Speaker 2: go on to say they hate scientists, so that's I

45
00:02:46,240 --> 00:02:48,400
Speaker 2: feel like they're not interested in what we have to say.

46
00:02:48,320 --> 00:02:50,760
Speaker 1: Thumbs down for that. Well, you know, there's a lot

47
00:02:50,760 --> 00:02:53,280
Speaker 1: of really interesting stuff there. Like, on one hand, some

48
00:02:53,320 --> 00:02:56,520
Speaker 1: of the stuff we figured out is as fascinating and

49
00:02:56,639 --> 00:03:00,200
Speaker 1: amazing as the kind of magic that exists in those novels.

50
00:03:00,280 --> 00:03:04,040
Speaker 1: You know, like internet communication, I'm talking to you in

51
00:03:04,120 --> 00:03:08,640
Speaker 1: real time across the country. You know, like that's basically magic,

52
00:03:09,680 --> 00:03:12,840
Speaker 1: but it's explained, it's understood. And there's something about magic

53
00:03:12,880 --> 00:03:16,240
Speaker 1: which is that it's not explained and not understood, which

54
00:03:16,320 --> 00:03:18,760
Speaker 1: makes it sort of special. And the thing about magnets

55
00:03:19,320 --> 00:03:22,160
Speaker 1: is that, yeah, we know how electromagnetism works, and we

56
00:03:22,200 --> 00:03:25,320
Speaker 1: can even understand it on the quantum level, and qwd's

57
00:03:25,360 --> 00:03:27,160
Speaker 1: the most successful theory of all time dot dot dot

58
00:03:27,200 --> 00:03:29,639
Speaker 1: dot dot. And yet when you play with magnets, they

59
00:03:29,680 --> 00:03:32,480
Speaker 1: do feel a little magical. They do feel like a

60
00:03:32,520 --> 00:03:34,600
Speaker 1: little bit beyond physics, don't they.

61
00:03:34,600 --> 00:03:36,520
Speaker 2: They absolutely do, and I think if you were to

62
00:03:36,520 --> 00:03:39,200
Speaker 2: talk about like mag love trains, which I suspect is

63
00:03:39,200 --> 00:03:41,760
Speaker 2: a slightly different situation, but I can't say I know

64
00:03:41,840 --> 00:03:43,680
Speaker 2: about it, and you were to explain that to someone

65
00:03:43,680 --> 00:03:47,280
Speaker 2: from like one hundred years ago, that and Zoom would

66
00:03:47,320 --> 00:03:50,960
Speaker 2: absolutely feel like magic. You know, Like I feel like

67
00:03:51,120 --> 00:03:53,080
Speaker 2: the life we live in would feel like magic for

68
00:03:53,120 --> 00:03:54,160
Speaker 2: people one hundred years ago.

69
00:03:54,200 --> 00:03:57,120
Speaker 1: I agree, Yeah, yeah, Like we went to the moon, man,

70
00:03:57,280 --> 00:04:01,880
Speaker 1: we really did the moon in the sky, that's right. Yeah.

71
00:04:01,920 --> 00:04:04,880
Speaker 1: And so on today's show, we're going to ruin magnets

72
00:04:04,880 --> 00:04:07,240
Speaker 1: a little bit for all of y'all. Right, magnets are

73
00:04:07,280 --> 00:04:09,720
Speaker 1: not magic, and we're gonna explain the science of them.

74
00:04:10,000 --> 00:04:12,240
Speaker 1: And I did something a little bit different with this episode.

75
00:04:12,400 --> 00:04:16,279
Speaker 1: I wanted to really answer people's questions to resolve their

76
00:04:16,440 --> 00:04:20,159
Speaker 1: magnetic mysteries. So before I even got started writing this episode,

77
00:04:20,240 --> 00:04:23,000
Speaker 1: I went out and asked people, what are the deepest

78
00:04:23,040 --> 00:04:26,760
Speaker 1: mysteries of magnets? What do people need explaining? How can

79
00:04:26,800 --> 00:04:30,279
Speaker 1: we ruin the magic of magnets for all of our listeners.

80
00:04:30,560 --> 00:04:35,000
Speaker 2: Our apologies to the Jugglers for demystifying the magic of magnets.

81
00:04:36,520 --> 00:04:38,560
Speaker 1: So here's what our listeners had to say if you

82
00:04:38,600 --> 00:04:41,400
Speaker 1: would like to contribute your voice for future episodes. Please

83
00:04:41,440 --> 00:04:43,280
Speaker 1: don't be shy. We'd love to hear from you. Write

84
00:04:43,279 --> 00:04:47,400
Speaker 1: to us two questions at Danielankelly dot org. In the meantime,

85
00:04:47,480 --> 00:04:49,360
Speaker 1: think about it for a moment. What do you think

86
00:04:49,440 --> 00:04:53,560
Speaker 1: is the deepest mystery of magnets? Here's what listeners had

87
00:04:53,560 --> 00:04:57,680
Speaker 1: to say, how migratory birds are able to detect magnetic fields.

88
00:04:57,880 --> 00:05:00,159
Speaker 3: To me, the most mysterious thing about magnetism is that

89
00:05:00,200 --> 00:05:02,920
Speaker 3: it's not constantly canceling itself out, that we can have

90
00:05:03,000 --> 00:05:07,039
Speaker 3: magnets at all, and that the atoms aren't just arranging

91
00:05:07,080 --> 00:05:09,640
Speaker 3: themselves in such a way that the positive and negative

92
00:05:09,720 --> 00:05:13,200
Speaker 3: are canceling out in any macroscale sort of way.

93
00:05:13,640 --> 00:05:16,560
Speaker 4: Historically, I wonder if magnetism is one of the earliest

94
00:05:16,560 --> 00:05:18,960
Speaker 4: to perceive intersections between magic and science.

95
00:05:19,360 --> 00:05:23,400
Speaker 2: It's a mystery why Magnet and Steel was Walter Egan's

96
00:05:23,480 --> 00:05:25,400
Speaker 2: only hit, because that's a great song.

97
00:05:25,839 --> 00:05:29,600
Speaker 4: I can get more magnets by breaking one into pieces.

98
00:05:29,960 --> 00:05:30,719
Speaker 1: Total mystery.

99
00:05:31,080 --> 00:05:33,960
Speaker 5: Spin creates it, but spin isn't really spinning, is it?

100
00:05:34,360 --> 00:05:37,480
Speaker 4: And then moving charges make magnetic fields, and magnetic fields

101
00:05:37,520 --> 00:05:42,479
Speaker 4: make moving charges. It's basically the universe's most passive aggressive friendship. Also,

102
00:05:42,520 --> 00:05:45,840
Speaker 4: magnetism is just electricity from a different perspective.

103
00:05:45,760 --> 00:05:48,560
Speaker 3: How magnets can attract and repul without touching.

104
00:05:48,920 --> 00:05:53,320
Speaker 1: There is no such thing as a monopole. There always dipoles.

105
00:05:53,600 --> 00:05:57,600
Speaker 1: Why is it binary? Why isn't there a third attraction?

106
00:05:57,800 --> 00:05:59,839
Speaker 1: So it all works in a triangle?

107
00:06:00,360 --> 00:06:03,640
Speaker 6: Is the repellent force between two magnets and the attractive

108
00:06:03,640 --> 00:06:06,479
Speaker 6: force between a magnet and an object that's attracted to it?

109
00:06:06,520 --> 00:06:10,600
Speaker 6: I think that force. Both of those forces are very mysterious.

110
00:06:10,880 --> 00:06:12,560
Speaker 3: I think is the fact that the north and south

111
00:06:12,640 --> 00:06:15,600
Speaker 3: pull switch and we don't know why or like what

112
00:06:15,680 --> 00:06:16,440
Speaker 3: causes it?

113
00:06:16,560 --> 00:06:19,160
Speaker 2: All right, Daniel, magnets, how do they work?

114
00:06:21,000 --> 00:06:22,719
Speaker 1: I don't know. It sounds like we should invite Walter

115
00:06:22,839 --> 00:06:24,440
Speaker 1: Egan to sing us his song.

116
00:06:24,839 --> 00:06:27,239
Speaker 2: I have to admit I haven't heard of Walter Egan.

117
00:06:27,279 --> 00:06:29,719
Speaker 2: Not that I'm like a great music connoisseur, but have

118
00:06:29,800 --> 00:06:33,719
Speaker 2: you heard of Walter Egan? It's no fair if you

119
00:06:33,800 --> 00:06:34,960
Speaker 2: google it, Daniel.

120
00:06:38,640 --> 00:06:41,520
Speaker 1: So, Walter Egan's great hit apparently came out in nineteen

121
00:06:41,560 --> 00:06:43,920
Speaker 1: seventy eight, and I was only three, so I think

122
00:06:43,920 --> 00:06:45,480
Speaker 1: it was a little too young to enjoy it at

123
00:06:45,480 --> 00:06:49,000
Speaker 1: the time. So no, I'm not familiar with Walter Egan's

124
00:06:49,240 --> 00:06:51,440
Speaker 1: only hit, but I'm gonna enjoy it after this recording.

125
00:06:51,680 --> 00:06:54,720
Speaker 2: Yeah, me as well. We'll check it out. But then,

126
00:06:54,760 --> 00:06:57,720
Speaker 2: how do magnets work, Daniel, Yeah.

127
00:06:57,720 --> 00:07:01,560
Speaker 1: So magnets are amazing and fascinating, but they're best understood

128
00:07:01,640 --> 00:07:04,520
Speaker 1: if we start with a related topic, which is electricity.

129
00:07:04,560 --> 00:07:08,360
Speaker 1: Because electricity magnetism very closely connected, and we can use

130
00:07:08,400 --> 00:07:12,000
Speaker 1: our intuition for electricity to understand how magnets are similar

131
00:07:12,040 --> 00:07:15,320
Speaker 1: and also crucially different. So let's step away for a

132
00:07:15,360 --> 00:07:18,320
Speaker 1: moment and start with electric charge. So we know that

133
00:07:18,360 --> 00:07:21,320
Speaker 1: you can have positive and negative charges, right, like the electron,

134
00:07:21,400 --> 00:07:24,680
Speaker 1: what's its charge? It's negative one. Right, the proton, what's

135
00:07:24,720 --> 00:07:29,480
Speaker 1: its charge? It's positive one. There's no like balancing charge

136
00:07:29,560 --> 00:07:32,360
Speaker 1: to the electron. You can have a proton and electron together,

137
00:07:32,720 --> 00:07:35,080
Speaker 1: and you can make a neutral object or even like

138
00:07:35,080 --> 00:07:37,120
Speaker 1: a dipole where you have like more negative and one

139
00:07:37,120 --> 00:07:39,400
Speaker 1: side more positive on the other. But you can also

140
00:07:39,480 --> 00:07:42,480
Speaker 1: crucially separate the electron and the positron. You can just

141
00:07:42,520 --> 00:07:45,520
Speaker 1: have in principle, an empty universe with an electron in it,

142
00:07:45,880 --> 00:07:48,120
Speaker 1: or an empty universe with just a proton in it.

143
00:07:48,440 --> 00:07:50,800
Speaker 1: So you can have positive charges, negative charges, and they

144
00:07:50,800 --> 00:07:53,840
Speaker 1: can be isolated and separate. Right. We call these things

145
00:07:54,160 --> 00:07:57,880
Speaker 1: monopoles mono because they're just one right, So they're alone,

146
00:07:57,920 --> 00:08:01,160
Speaker 1: they don't have to come in pairs. Crucially, they are

147
00:08:01,200 --> 00:08:03,920
Speaker 1: the source of electric fields, right, Like if you have

148
00:08:03,960 --> 00:08:06,840
Speaker 1: an electron in space, it makes an electric field, so

149
00:08:06,880 --> 00:08:10,320
Speaker 1: it could push and pull on other electrons. A proton

150
00:08:10,400 --> 00:08:13,440
Speaker 1: can also make electric fields, and if you like to

151
00:08:13,520 --> 00:08:18,360
Speaker 1: draw field lines, these lines start from the electron or

152
00:08:18,400 --> 00:08:22,360
Speaker 1: the proton, right. So that's the basics of electric fields

153
00:08:22,400 --> 00:08:23,200
Speaker 1: and charges.

154
00:08:23,480 --> 00:08:27,120
Speaker 2: So to clarify for monopoles, when they're alone, do you

155
00:08:27,200 --> 00:08:30,160
Speaker 2: have to have just one electron alone or you can

156
00:08:30,200 --> 00:08:32,160
Speaker 2: have a bunch of electrons as long as they don't

157
00:08:32,200 --> 00:08:33,200
Speaker 2: let any protons in.

158
00:08:33,400 --> 00:08:36,400
Speaker 1: Yeah, great question. You can have just one electron alone.

159
00:08:36,400 --> 00:08:39,000
Speaker 1: You can also have like ten thousand electrons and they're

160
00:08:39,040 --> 00:08:43,120
Speaker 1: a source of negative charge. So that's ten thousand monopoles,

161
00:08:43,120 --> 00:08:47,800
Speaker 1: which makes an effective monopole. It's still only a negative charge.

162
00:08:47,840 --> 00:08:51,080
Speaker 1: It's a negative charge. It's a source of the electric field.

163
00:08:51,280 --> 00:08:55,040
Speaker 2: Okay, so the word monopole refers to one electron alone

164
00:08:55,200 --> 00:08:58,520
Speaker 2: or a bunch of electrons together. It can be either

165
00:08:58,559 --> 00:09:00,520
Speaker 2: singular or plural elonetrons.

166
00:09:00,679 --> 00:09:04,960
Speaker 1: Yeah, okay, yeah, I see how that's confusing. What we

167
00:09:05,000 --> 00:09:07,520
Speaker 1: mean by mono is not the number of electrons, but

168
00:09:07,559 --> 00:09:10,720
Speaker 1: the fact that there is no balancing pole, because a diepole,

169
00:09:10,800 --> 00:09:13,320
Speaker 1: in contrast, is a positive and a negative, where a

170
00:09:13,360 --> 00:09:16,800
Speaker 1: net charge is zero, but a monopole has negative or

171
00:09:16,800 --> 00:09:20,400
Speaker 1: positive net charge, even if it's one or seventy five electrons.

172
00:09:20,440 --> 00:09:21,920
Speaker 2: We got to make sure that we're clear because we've

173
00:09:21,920 --> 00:09:25,040
Speaker 2: got to bring the juggalos along with this conversation. Wait,

174
00:09:25,080 --> 00:09:29,600
Speaker 2: can I just check the jugglos? What are icps.

175
00:09:29,280 --> 00:09:30,600
Speaker 1: Going down that rabbit hole?

176
00:09:30,720 --> 00:09:34,240
Speaker 2: Here we go, not very far. They are juggalos. Okay,

177
00:09:34,240 --> 00:09:42,240
Speaker 2: they are juggalos. Oh got a picture pop brought back

178
00:09:42,280 --> 00:09:42,760
Speaker 2: to my youth.

179
00:09:42,800 --> 00:09:46,360
Speaker 1: Okay, all right, So that's electricity. What about magnetism. Well,

180
00:09:46,400 --> 00:09:48,320
Speaker 1: as we've talked about on the show a few times,

181
00:09:48,320 --> 00:09:52,559
Speaker 1: this concept of charge extends to other forces. We call

182
00:09:52,600 --> 00:09:55,319
Speaker 1: it charge, but really the efficient name is electric charge,

183
00:09:55,320 --> 00:09:58,880
Speaker 1: because we have also magnetic charges and weak force charges

184
00:09:58,920 --> 00:10:02,480
Speaker 1: and strong force charges. Okay, so magnetic charges, what do

185
00:10:02,520 --> 00:10:04,720
Speaker 1: we call them? We don't call them plus or minus.

186
00:10:05,040 --> 00:10:08,120
Speaker 1: We call them north or south. And that's a historical

187
00:10:08,200 --> 00:10:11,440
Speaker 1: anomaly because we associated with the Earth's magnetic field, which

188
00:10:11,480 --> 00:10:14,880
Speaker 1: happens to be aligned mostly with the north and south poles,

189
00:10:14,920 --> 00:10:18,079
Speaker 1: and so we call it a magnetic north or magnetic south.

190
00:10:18,480 --> 00:10:21,560
Speaker 1: But physically and conceptually abstractly, you should think of these

191
00:10:21,640 --> 00:10:26,280
Speaker 1: insame category as electric plus and minus, just for magnetism

192
00:10:26,360 --> 00:10:27,800
Speaker 1: instead of for electricity.

193
00:10:28,240 --> 00:10:31,400
Speaker 2: And so north is plus and south is minus.

194
00:10:31,480 --> 00:10:34,679
Speaker 1: No, No, not necessarily, It's just two labels like plus

195
00:10:34,679 --> 00:10:36,520
Speaker 1: and minus are arbitrary. Right, We could have called the

196
00:10:36,520 --> 00:10:39,680
Speaker 1: electron plus and the proton minus. Ben Franklin went the

197
00:10:39,720 --> 00:10:43,040
Speaker 1: other way. There's no necessary connection between north and south

198
00:10:43,080 --> 00:10:45,920
Speaker 1: or plus or minus. You're just biased for the northern hemisphere.

199
00:10:45,960 --> 00:10:49,160
Speaker 2: Kelly, Well, I like where I live, but I'm sure

200
00:10:49,200 --> 00:10:51,560
Speaker 2: the southern hemisphere is lovely as well. It was when

201
00:10:51,600 --> 00:10:54,240
Speaker 2: I visited. So are we going to get to why

202
00:10:54,280 --> 00:10:56,160
Speaker 2: the Earth has a magnetic field too?

203
00:10:56,760 --> 00:10:59,240
Speaker 1: Yes, and what we don't understand about it and how

204
00:10:59,280 --> 00:11:01,720
Speaker 1: weird it is definitely going to dig into that magic

205
00:11:02,120 --> 00:11:05,360
Speaker 1: all right. So, so far magnetism is very similar to electricity.

206
00:11:05,440 --> 00:11:09,319
Speaker 1: Here's the crucial difference. There are no monopoles. You can

207
00:11:09,360 --> 00:11:12,160
Speaker 1: never have just a magnetic north the way you can

208
00:11:12,320 --> 00:11:15,680
Speaker 1: have a negative electric charge or a positive electric charge

209
00:11:15,679 --> 00:11:18,360
Speaker 1: by itself. As far as we know, there is nothing which,

210
00:11:18,400 --> 00:11:20,600
Speaker 1: if you put it in an empty universe, would just

211
00:11:20,679 --> 00:11:23,760
Speaker 1: have a magnetic north or a magnetic south. They only

212
00:11:23,800 --> 00:11:28,720
Speaker 1: come and diepoles, pairs of north and south together. Why yeah,

213
00:11:28,920 --> 00:11:30,760
Speaker 1: why is a great question, and we don't have a

214
00:11:30,760 --> 00:11:32,920
Speaker 1: good answer to that. We think, actually, there should be

215
00:11:33,240 --> 00:11:36,520
Speaker 1: Like physics actually wants there to be a monopole. It

216
00:11:36,559 --> 00:11:39,320
Speaker 1: would be a nice balance. We'd like symmetry in the universe.

217
00:11:39,400 --> 00:11:42,240
Speaker 1: We like symmetry in the laws of physics. And if

218
00:11:42,240 --> 00:11:44,040
Speaker 1: you just looked at the equations, you're like, oh, yeah,

219
00:11:44,040 --> 00:11:46,720
Speaker 1: there should totally be monopoles. But we've never seen one.

220
00:11:47,040 --> 00:11:50,400
Speaker 1: We've never found anything out there that's the magnetic equivalent

221
00:11:50,559 --> 00:11:53,880
Speaker 1: of an electron, Like an electron carries charge just on

222
00:11:53,920 --> 00:11:56,560
Speaker 1: its own, just a negative charge, no balance. We've never

223
00:11:56,640 --> 00:12:01,240
Speaker 1: found anything out there that carries magnetic southgetic north. The

224
00:12:01,280 --> 00:12:06,600
Speaker 1: only way we've ever made magnets is by moving electric charges.

225
00:12:07,120 --> 00:12:11,880
Speaker 1: There's this connection between electricity and magnetism. Electricity can generate magnetism,

226
00:12:11,920 --> 00:12:15,280
Speaker 1: magnetism can generate electricity. That's the only way we can

227
00:12:15,280 --> 00:12:19,679
Speaker 1: make magnetism through charges, not through pure magnetic sources. There

228
00:12:19,720 --> 00:12:22,720
Speaker 1: are no sources of magnetism that are pure.

229
00:12:22,679 --> 00:12:26,000
Speaker 2: Okay, So when I have a magnet, it's because of

230
00:12:26,360 --> 00:12:28,680
Speaker 2: stuff electrons and protons are doing in there.

231
00:12:28,920 --> 00:12:32,480
Speaker 1: Exactly. One of Maxwell's equations, one of the crucial equations

232
00:12:32,480 --> 00:12:37,760
Speaker 1: for electromagnetism, tells us that charges in motion make magnetic fields.

233
00:12:38,360 --> 00:12:40,640
Speaker 1: So you take a bunch of electrons, you run them

234
00:12:40,640 --> 00:12:43,320
Speaker 1: down a wire. What happens, They make a magnetic field

235
00:12:43,360 --> 00:12:47,160
Speaker 1: around them. So you can make magnetic fields from charges

236
00:12:47,200 --> 00:12:50,559
Speaker 1: in motion, but you can't make them monopoles. You can

237
00:12:50,600 --> 00:12:54,080
Speaker 1: only make dipole fields. A charge in motion can make

238
00:12:54,120 --> 00:12:56,079
Speaker 1: a magnetic field, but it has to make a north

239
00:12:56,160 --> 00:12:59,000
Speaker 1: and the south at the same time. You can't just

240
00:12:59,120 --> 00:13:01,600
Speaker 1: generate a north. You can't just generate a south.

241
00:13:01,960 --> 00:13:04,719
Speaker 2: And is that the end here? The answer is, we

242
00:13:04,760 --> 00:13:06,480
Speaker 2: don't know why that's the case. I think that's what

243
00:13:06,520 --> 00:13:07,120
Speaker 2: you were saying.

244
00:13:07,240 --> 00:13:11,360
Speaker 1: We understand why you can't generate a monopole from electric charges.

245
00:13:11,520 --> 00:13:13,960
Speaker 1: We don't understand why there aren't monopoles out there that

246
00:13:14,080 --> 00:13:17,240
Speaker 1: just make magnetic north or make magnetic south. We don't know,

247
00:13:17,280 --> 00:13:19,480
Speaker 1: and there might be it could be that they are

248
00:13:19,520 --> 00:13:21,360
Speaker 1: somewhere in the universe. But if they are, they are

249
00:13:21,480 --> 00:13:24,640
Speaker 1: very rare. We've never seen them. We've looked for them,

250
00:13:24,679 --> 00:13:26,120
Speaker 1: and we can dig into that in a minute. But

251
00:13:26,200 --> 00:13:28,960
Speaker 1: every magnetic field we've ever made or seen, or that

252
00:13:29,040 --> 00:13:32,520
Speaker 1: you've used, doesn't come from some inherent source of the

253
00:13:32,600 --> 00:13:36,559
Speaker 1: magnetic monopole, the way electric fields come from electrons or protons.

254
00:13:37,040 --> 00:13:39,319
Speaker 1: It comes from electric charges in motion.

255
00:13:39,600 --> 00:13:44,080
Speaker 2: So why do electric charges in motion result in a

256
00:13:44,160 --> 00:13:46,400
Speaker 2: north and a south? Have I just asked the same

257
00:13:46,440 --> 00:13:47,679
Speaker 2: question in a slightly different way?

258
00:13:47,800 --> 00:13:50,439
Speaker 1: Okay, no, no, No, that's a great question. And this

259
00:13:50,520 --> 00:13:52,120
Speaker 1: is a very mathematical answer if you look at the

260
00:13:52,120 --> 00:13:55,480
Speaker 1: structure of Maxwell's equations. But intuitively, the way to think

261
00:13:55,480 --> 00:13:58,240
Speaker 1: about it is think about the magnetic field that's generated

262
00:13:58,240 --> 00:14:00,840
Speaker 1: when electron moves down a wire. It's got to be

263
00:14:00,880 --> 00:14:03,040
Speaker 1: in a loop. It's a curl equation, so it makes

264
00:14:03,040 --> 00:14:05,160
Speaker 1: a magnetic field in a loop around the wire, and

265
00:14:05,200 --> 00:14:08,440
Speaker 1: there's no source there. The magnetic field line starts and

266
00:14:08,559 --> 00:14:11,080
Speaker 1: ends on itself. It doesn't start or end in a

267
00:14:11,080 --> 00:14:15,800
Speaker 1: specific location, so there's no end points there. Monopoles have

268
00:14:16,080 --> 00:14:19,480
Speaker 1: end points for magnetic fields, but an electronic motion can't

269
00:14:19,480 --> 00:14:21,920
Speaker 1: make that. It can just make a loop that ends

270
00:14:21,920 --> 00:14:24,440
Speaker 1: and starts on itself, and that has a north and

271
00:14:24,480 --> 00:14:28,360
Speaker 1: the south all together, and so it can't generate these sources.

272
00:14:29,040 --> 00:14:31,200
Speaker 1: So let's talk about the two kinds of magnets that

273
00:14:31,240 --> 00:14:35,080
Speaker 1: we have experience with the kitchen magnet, like a permanent magnet,

274
00:14:35,160 --> 00:14:38,240
Speaker 1: like a pheraohmagnet, and then we'll talk about electromagnet, so

275
00:14:38,280 --> 00:14:41,000
Speaker 1: a ferromagnet. You might ask, like, I have this thing

276
00:14:41,040 --> 00:14:43,800
Speaker 1: on my fridge, I'm not running electricity through it. What

277
00:14:43,960 --> 00:14:47,080
Speaker 1: charges are in motion? And this is exactly the question

278
00:14:47,240 --> 00:14:50,120
Speaker 1: I just got yesterday as I was prepping this episode.

279
00:14:50,440 --> 00:14:53,240
Speaker 1: So here's David Naylor asking us this question.

280
00:14:53,680 --> 00:14:57,320
Speaker 5: Hi, Daniel and Kelly. I'm told that magnetic fields are

281
00:14:57,360 --> 00:15:02,040
Speaker 5: generated by moving electron charges. So my question for you

282
00:15:02,160 --> 00:15:06,320
Speaker 5: is what moving electron charge is powering two magnets that

283
00:15:06,400 --> 00:15:08,800
Speaker 5: I hold in my hand. Thank you both for an

284
00:15:08,840 --> 00:15:11,200
Speaker 5: awesome show, and I can't wait to hear your answer.

285
00:15:11,600 --> 00:15:14,000
Speaker 2: Well, David, since we both asked exactly the same question,

286
00:15:14,480 --> 00:15:16,480
Speaker 2: I've got to say that this is a truly great

287
00:15:16,520 --> 00:15:21,160
Speaker 2: and insightful question. What is the answer, Daniel?

288
00:15:21,440 --> 00:15:25,080
Speaker 1: Are you inviting David to join your insane magnet posse?

289
00:15:26,240 --> 00:15:29,840
Speaker 2: Yes, the megalows.

290
00:15:31,040 --> 00:15:35,240
Speaker 1: Right, So what's moving here to generate this magnet? So

291
00:15:35,400 --> 00:15:38,840
Speaker 1: zoom in on the magnet. You have molecules of iron.

292
00:15:39,280 --> 00:15:42,480
Speaker 1: Inside those molecules, you have the nucleus, and you also

293
00:15:42,480 --> 00:15:45,640
Speaker 1: have electrons whizzing around. Right. Well, all of these fundamental

294
00:15:45,640 --> 00:15:49,280
Speaker 1: particles have something we call spin. It's quantum spin. They're

295
00:15:49,280 --> 00:15:52,800
Speaker 1: not physically spinning, but they have this property which is

296
00:15:52,880 --> 00:15:55,840
Speaker 1: very closely related to spin. And one of the reasons

297
00:15:55,840 --> 00:15:58,280
Speaker 1: we say that this property is related to spin is

298
00:15:58,280 --> 00:16:00,200
Speaker 1: that it has a lot of the same behavior as

299
00:16:00,280 --> 00:16:04,400
Speaker 1: classical spin. Like if you take a metallic sphere that's

300
00:16:04,520 --> 00:16:08,400
Speaker 1: charged and you spun it, it would generate a magnetic field. Why,

301
00:16:08,480 --> 00:16:11,320
Speaker 1: because you got charges in motion. You have charges attached

302
00:16:11,320 --> 00:16:13,400
Speaker 1: to the surface of the sphere and they're in motion.

303
00:16:13,680 --> 00:16:16,920
Speaker 1: Generates a magnetic field. Cool. If you have a fundamental

304
00:16:16,920 --> 00:16:19,440
Speaker 1: particle like an electron, that's charged and you give it

305
00:16:19,560 --> 00:16:23,160
Speaker 1: quantum spin, it also has a little magnetic field. It

306
00:16:23,200 --> 00:16:26,040
Speaker 1: has a little north and a little south. Why is

307
00:16:26,080 --> 00:16:29,160
Speaker 1: that exactly? It's a little bit circular. Like we call

308
00:16:29,240 --> 00:16:32,400
Speaker 1: it spin because we see that it generates magnetic field,

309
00:16:32,400 --> 00:16:34,720
Speaker 1: and so we're like, well, whatever, this quantum spin thing

310
00:16:34,920 --> 00:16:38,520
Speaker 1: is it has angular momentum and it generates magnetic fields.

311
00:16:38,560 --> 00:16:40,680
Speaker 1: So it's a lot like spin, So we'll call it spin.

312
00:16:41,400 --> 00:16:44,160
Speaker 1: So you can either say, well, something is happening with

313
00:16:44,200 --> 00:16:47,120
Speaker 1: the electron to generate these mini mechnetic fields and it's

314
00:16:47,120 --> 00:16:48,880
Speaker 1: related to spin, or you can say we call it

315
00:16:48,880 --> 00:16:51,760
Speaker 1: spin because it generates magnetic fields. It's sort of two

316
00:16:51,840 --> 00:16:55,280
Speaker 1: sides of the same coin. But basically each little electron

317
00:16:55,440 --> 00:16:56,960
Speaker 1: is its own mini magnet.

318
00:16:57,360 --> 00:16:59,440
Speaker 2: Okay, So I'm just trying to make sure I've got

319
00:16:59,480 --> 00:17:01,560
Speaker 2: my head around them. So you were saying that electrons

320
00:17:01,640 --> 00:17:05,879
Speaker 2: are like all negative, totally negative, but they can still

321
00:17:05,880 --> 00:17:08,240
Speaker 2: have a north in a south because north and south

322
00:17:08,320 --> 00:17:10,639
Speaker 2: is not the same thing as positive and minus, despite

323
00:17:10,640 --> 00:17:12,560
Speaker 2: the fact that I have locked that into my brain.

324
00:17:13,119 --> 00:17:15,679
Speaker 2: So what does it really mean then, to say that

325
00:17:15,680 --> 00:17:17,760
Speaker 2: an electron has a north in a south pole.

326
00:17:18,119 --> 00:17:20,719
Speaker 1: So electrons can spin in two different ways. They can

327
00:17:20,760 --> 00:17:23,280
Speaker 1: spin up or spin down. If it spins up, then

328
00:17:23,280 --> 00:17:24,800
Speaker 1: it has a north and a south pole. If it

329
00:17:24,840 --> 00:17:27,000
Speaker 1: spins down, then it has a south and a north pole,

330
00:17:27,000 --> 00:17:28,920
Speaker 1: if you like to think about it that way. So

331
00:17:28,960 --> 00:17:31,720
Speaker 1: the direction of its spin determines which side of it

332
00:17:31,800 --> 00:17:34,320
Speaker 1: the electron is north and which side is south. And

333
00:17:34,359 --> 00:17:37,240
Speaker 1: then if you pass them through a magnetic field, spin

334
00:17:37,320 --> 00:17:39,680
Speaker 1: up electrons will go one way and spin down electrons

335
00:17:39,680 --> 00:17:41,840
Speaker 1: will go the other way. This is actually the crucial

336
00:17:41,880 --> 00:17:45,280
Speaker 1: experiment that revealed that electrons could only have two spins

337
00:17:45,359 --> 00:17:47,200
Speaker 1: up or down as they passed them through a magnet.

338
00:17:47,400 --> 00:17:49,959
Speaker 1: And they didn't see a whole distribution of electron deflections.

339
00:17:50,200 --> 00:17:53,040
Speaker 1: They saw two deflections either left or right. They were

340
00:17:53,080 --> 00:17:56,040
Speaker 1: tightly clustered. So you can use the magnetic field of

341
00:17:56,040 --> 00:17:59,280
Speaker 1: the electron to measure its spin because it's not closely connected.

342
00:17:59,520 --> 00:18:02,120
Speaker 1: So to answer David's question directly, like, we don't want

343
00:18:02,160 --> 00:18:04,600
Speaker 1: to say that electron is in motion because it's a

344
00:18:04,680 --> 00:18:06,800
Speaker 1: quantum particle and it doesn't have a surface, and it's

345
00:18:06,800 --> 00:18:10,040
Speaker 1: not really spinning. But the quantum spin of the electron

346
00:18:10,480 --> 00:18:14,800
Speaker 1: is analogous to electric current, and together with the electrons

347
00:18:14,920 --> 00:18:17,960
Speaker 1: charge that generates a little tiny dipole magnet.

348
00:18:18,200 --> 00:18:20,680
Speaker 2: Okay, so I'm thinking about my kitchen magnet and I've

349
00:18:20,720 --> 00:18:23,680
Speaker 2: got some electrons spinning up, some electrons spinning down. Is

350
00:18:23,720 --> 00:18:26,440
Speaker 2: the top of my magnet, yeah, or the bottom whatever?

351
00:18:26,520 --> 00:18:28,840
Speaker 2: Is one side of the magnet where my electrons that

352
00:18:28,840 --> 00:18:31,960
Speaker 2: are spinning up live and the bottom side is where

353
00:18:31,960 --> 00:18:36,040
Speaker 2: my electrons that spin down live. And why don't they

354
00:18:36,680 --> 00:18:37,359
Speaker 2: mix together?

355
00:18:37,680 --> 00:18:40,080
Speaker 1: Does that seem like a cozy little neighborhood organization.

356
00:18:40,800 --> 00:18:42,520
Speaker 2: It sounds like they're segregating. I don't like that one.

357
00:18:42,560 --> 00:18:44,880
Speaker 1: Oh no, you're right exactly. Let's mix everybody.

358
00:18:45,080 --> 00:18:45,280
Speaker 5: Yeah.

359
00:18:45,320 --> 00:18:47,240
Speaker 1: Well, if you just take a hunk of iron out

360
00:18:47,240 --> 00:18:50,240
Speaker 1: of the earth, then it's got all these little electrons

361
00:18:50,280 --> 00:18:52,120
Speaker 1: and they have all their little magnetic fields, but they're

362
00:18:52,119 --> 00:18:54,680
Speaker 1: all pointing in random directions, and so it doesn't act

363
00:18:54,720 --> 00:18:57,479
Speaker 1: like a magnet. And actually, if you zoom in, you

364
00:18:57,560 --> 00:19:00,920
Speaker 1: find that they have organized themselves into little megas knetic domains,

365
00:19:01,000 --> 00:19:03,879
Speaker 1: little clusters where they all point the same direction, and

366
00:19:03,920 --> 00:19:06,480
Speaker 1: then there's another cluster pointing the opposite direction. But on

367
00:19:06,520 --> 00:19:09,680
Speaker 1: a macroscopic scale, they all add up to nothing. They

368
00:19:09,680 --> 00:19:12,240
Speaker 1: cancel each other out. What happens if you bring another

369
00:19:12,320 --> 00:19:15,600
Speaker 1: magnet nearby is it'll start to flip those guys, right.

370
00:19:15,640 --> 00:19:18,439
Speaker 1: Those magnets will align with the other magnets. So that's

371
00:19:18,480 --> 00:19:20,680
Speaker 1: why if you bring like a hunk of iron near

372
00:19:20,680 --> 00:19:24,119
Speaker 1: a magnet, it gets magnetized. What you're doing is just

373
00:19:24,160 --> 00:19:26,800
Speaker 1: rearranging all of those electrons, so they're no longer fighting

374
00:19:26,840 --> 00:19:29,320
Speaker 1: each other, and they're now all aligned in the same direction,

375
00:19:29,640 --> 00:19:31,800
Speaker 1: and they add up instead of canceling out. They add

376
00:19:31,840 --> 00:19:33,639
Speaker 1: up to an overall magnetic field.

377
00:19:33,800 --> 00:19:35,560
Speaker 2: Okay, so you're not just moving them around so they're

378
00:19:35,560 --> 00:19:37,639
Speaker 2: in like groups, you're actually flipping them all to the

379
00:19:37,640 --> 00:19:38,200
Speaker 2: same direction.

380
00:19:38,400 --> 00:19:40,760
Speaker 1: Yeah, okay, And we're talking about electrons here because they're

381
00:19:40,760 --> 00:19:43,359
Speaker 1: easiest to think about. But it's not just the electrons

382
00:19:43,359 --> 00:19:46,119
Speaker 1: to have these magnetic fields. Protons of magnetic fields. Also,

383
00:19:46,359 --> 00:19:50,159
Speaker 1: the neutron even has its own residual magnetic field because

384
00:19:50,200 --> 00:19:53,320
Speaker 1: it has quarks inside of it which are charged, and

385
00:19:53,400 --> 00:19:56,280
Speaker 1: so you can measure the magnetic moment of the neutron

386
00:19:56,600 --> 00:19:59,760
Speaker 1: or of the proton or the electron. And so I'm

387
00:19:59,760 --> 00:20:02,520
Speaker 1: saying electrons, that really mean like all the particles inside

388
00:20:02,520 --> 00:20:04,880
Speaker 1: that add up to do this. And so you can

389
00:20:04,920 --> 00:20:08,639
Speaker 1: make pretty powerful magnets with the right materials that have

390
00:20:08,760 --> 00:20:11,919
Speaker 1: like the right structure and everything can align nicely. The

391
00:20:11,960 --> 00:20:15,000
Speaker 1: strongest magnet we've ever measured is about one and a

392
00:20:15,080 --> 00:20:20,959
Speaker 1: half tesla, which uses neodymium, iron and boron magnets, and

393
00:20:21,000 --> 00:20:23,520
Speaker 1: that's pretty powerful. I remember, the Earth's magnetic field is

394
00:20:23,560 --> 00:20:26,120
Speaker 1: almost a million times weaker than that. It's like thirty

395
00:20:26,240 --> 00:20:30,000
Speaker 1: to fifty micro tesla. So we can make very powerful

396
00:20:30,000 --> 00:20:32,520
Speaker 1: magnets that like are much more powerful than the Earth's

397
00:20:32,520 --> 00:20:33,240
Speaker 1: magnetic field.

398
00:20:33,359 --> 00:20:35,240
Speaker 2: So I'm thinking of the Brave Little Toaster and the

399
00:20:35,280 --> 00:20:37,800
Speaker 2: giant magnet that was picking stuff up to throw it

400
00:20:37,840 --> 00:20:41,600
Speaker 2: away in the landfill. So like one point for tesla?

401
00:20:42,040 --> 00:20:44,000
Speaker 2: How many? How many cars could you pick up with that?

402
00:20:44,080 --> 00:20:48,040
Speaker 2: What are we talking about? The Brave Little Toaster is

403
00:20:48,040 --> 00:20:48,560
Speaker 2: a classic.

404
00:20:49,520 --> 00:20:51,920
Speaker 1: I don't know, the Brave Little Toaster. I got a

405
00:20:51,960 --> 00:20:54,320
Speaker 1: lot of cultural homework to do after this episode.

406
00:20:54,440 --> 00:20:56,000
Speaker 2: We were born in the wrong decade, man.

407
00:20:55,960 --> 00:20:58,119
Speaker 1: Yeah, exactly. Well, you could pick up a lot of cars,

408
00:20:58,119 --> 00:21:01,200
Speaker 1: but actually, those big guys is that pickup cars tend

409
00:21:01,240 --> 00:21:04,680
Speaker 1: to be electro magnets. Because those are magnets you can

410
00:21:04,720 --> 00:21:09,240
Speaker 1: easily turn off and on, Like you could demagnify something

411
00:21:09,280 --> 00:21:11,560
Speaker 1: by trying to reflip it and re randomize all the

412
00:21:11,600 --> 00:21:14,879
Speaker 1: magnetic domains. But that's a lot of work. Instead, the

413
00:21:14,960 --> 00:21:17,479
Speaker 1: other kind of magnet is very easy to turn off

414
00:21:17,640 --> 00:21:18,960
Speaker 1: or on or reverse.

415
00:21:19,119 --> 00:21:21,640
Speaker 2: All right, magnet I've got on my fridge. It has

416
00:21:22,040 --> 00:21:26,159
Speaker 2: electrons spinning up on one side, electrons spinning down on

417
00:21:26,200 --> 00:21:29,919
Speaker 2: another side over time, would I expect those to like

418
00:21:30,400 --> 00:21:32,840
Speaker 2: decay where some of the ones that are going upstart

419
00:21:32,840 --> 00:21:35,399
Speaker 2: going down, or they just keep spinning in the direction

420
00:21:35,440 --> 00:21:38,880
Speaker 2: they're spinning in unless you do something to force them otherwise.

421
00:21:39,119 --> 00:21:40,919
Speaker 1: Yeah, this is a great question. People often ask this

422
00:21:41,160 --> 00:21:45,440
Speaker 1: because they imagine, like, why do magnets not lose their energy? Yeah,

423
00:21:45,440 --> 00:21:47,720
Speaker 1: but yeah, they just point in the same direction unless

424
00:21:47,760 --> 00:21:51,120
Speaker 1: something comes along and flips them. And so to demagnet

425
00:21:51,160 --> 00:21:53,439
Speaker 1: as a magnet, you'd have to like flip some of

426
00:21:53,480 --> 00:21:55,760
Speaker 1: the electrons or some of the particles one way and

427
00:21:55,800 --> 00:21:58,960
Speaker 1: not the other ones, which would be pretty tricky. And

428
00:21:59,119 --> 00:22:01,159
Speaker 1: they can just sit there and keep spinning in the

429
00:22:01,160 --> 00:22:05,120
Speaker 1: same direction without requiring any energy, you know, the same

430
00:22:05,119 --> 00:22:07,000
Speaker 1: way that like a rock can sit on the top

431
00:22:07,040 --> 00:22:09,679
Speaker 1: of a hill until somebody comes along and pushes It

432
00:22:09,720 --> 00:22:12,400
Speaker 1: takes energy to move the rock. So we can get

433
00:22:12,440 --> 00:22:14,720
Speaker 1: more into that in a minute. But yeah, they will

434
00:22:14,760 --> 00:22:17,000
Speaker 1: keep spinning in the same direction unless you come along

435
00:22:17,000 --> 00:22:17,720
Speaker 1: and scramble them.

436
00:22:17,800 --> 00:22:19,480
Speaker 2: All right, Well, let's take a break and get more

437
00:22:19,520 --> 00:22:40,560
Speaker 2: into that. All right, So my brain is stuck on

438
00:22:40,560 --> 00:22:42,960
Speaker 2: the brave little toaster now, and that electromagnet that was

439
00:22:43,000 --> 00:22:46,080
Speaker 2: picking cars up and slinging them around and throwing them down.

440
00:22:46,160 --> 00:22:47,520
Speaker 2: How do electromagnets work.

441
00:22:47,760 --> 00:22:51,920
Speaker 1: So electromagnets are like macroscopic versions. Right a minute ago,

442
00:22:51,920 --> 00:22:54,879
Speaker 1: we were talking about microscopic electrons. We say they have

443
00:22:54,960 --> 00:22:58,000
Speaker 1: charge and spin and therefore they generated magnetic field. Here,

444
00:22:58,040 --> 00:23:00,600
Speaker 1: we just take a bunch of electron, as we say,

445
00:23:00,600 --> 00:23:03,639
Speaker 1: whiz them around in a circle. That's charges in motion,

446
00:23:04,000 --> 00:23:07,560
Speaker 1: and so that generates a magnetic field. And you know

447
00:23:07,600 --> 00:23:10,400
Speaker 1: that's just says current. So if you want a straight

448
00:23:10,480 --> 00:23:13,199
Speaker 1: up magnetic field, for example, you make a loop of wire,

449
00:23:13,359 --> 00:23:16,480
Speaker 1: you like wrap wire around a cylinder and then as

450
00:23:16,520 --> 00:23:20,280
Speaker 1: the electrons go through that wire, they generate a magnetic

451
00:23:20,280 --> 00:23:23,840
Speaker 1: field in a loop around the wire, and then inside

452
00:23:24,080 --> 00:23:26,359
Speaker 1: that cylinder they all add up in the same direction

453
00:23:26,440 --> 00:23:28,840
Speaker 1: to make a big magnetic field. So this is what

454
00:23:28,920 --> 00:23:32,119
Speaker 1: an electromagnet is. It requires running a current. You have

455
00:23:32,160 --> 00:23:35,119
Speaker 1: to run energy through it. So you run out energy, boom,

456
00:23:35,160 --> 00:23:38,160
Speaker 1: your magnet turns off. This is for example, how an

457
00:23:38,160 --> 00:23:41,879
Speaker 1: electric motor works. Has an oscillating electromagnet. You turn the

458
00:23:42,040 --> 00:23:44,800
Speaker 1: magnet in one direction so it pulls on something. Then

459
00:23:44,840 --> 00:23:46,840
Speaker 1: you turn it on the other direction so it pushes

460
00:23:47,240 --> 00:23:50,720
Speaker 1: and it oscillates very rapidly to spin that rotor. Every

461
00:23:50,760 --> 00:23:53,679
Speaker 1: electric motor uses electro magnets.

462
00:23:53,920 --> 00:23:56,840
Speaker 2: What kind of things in our lives use electric motors?

463
00:23:57,359 --> 00:23:59,680
Speaker 1: Evs, Oh, yes, what.

464
00:23:59,640 --> 00:24:02,119
Speaker 2: About my hybrid? Does my hybrid use an electric motor?

465
00:24:02,200 --> 00:24:05,160
Speaker 1: Your hybrid definitely has an electric motor. And like every

466
00:24:05,280 --> 00:24:10,280
Speaker 1: robot you've ever seen and anything that goes like all

467
00:24:10,320 --> 00:24:13,000
Speaker 1: that stuff, you know, use this little electric motors. Electric

468
00:24:13,040 --> 00:24:16,160
Speaker 1: motors are everywhere and they're wonderful, and you can combine

469
00:24:16,200 --> 00:24:18,720
Speaker 1: these two things. You can take an electric motor and

470
00:24:19,000 --> 00:24:21,399
Speaker 1: instead of just having like a plastic cylinder whatever, you

471
00:24:21,440 --> 00:24:25,440
Speaker 1: can use a ferromagnetic cylinder. So now you're electromagnetic motor

472
00:24:25,560 --> 00:24:29,639
Speaker 1: is aligning the spinning electrons of the ferromagnet. So it

473
00:24:29,680 --> 00:24:32,720
Speaker 1: all adds up and you get like a really powerful magnet.

474
00:24:32,920 --> 00:24:35,280
Speaker 1: So people have been doing experiments to try, like make

475
00:24:35,359 --> 00:24:40,160
Speaker 1: the most powerful electromagnet possible to see like how much

476
00:24:40,520 --> 00:24:43,479
Speaker 1: magnetism can we have in a little bit of space?

477
00:24:43,640 --> 00:24:47,600
Speaker 2: So why would having a permanent magnet and then running

478
00:24:47,680 --> 00:24:51,200
Speaker 2: electricity through that make it more intense? Like you know,

479
00:24:51,280 --> 00:24:55,200
Speaker 2: you've already got the electrons doing their thing and running current.

480
00:24:55,240 --> 00:24:59,119
Speaker 2: Why does that supercharge the magnetism, magnet or magic.

481
00:24:59,520 --> 00:25:02,640
Speaker 1: There's no here, It's just that if you have the electromagnet,

482
00:25:02,680 --> 00:25:05,880
Speaker 1: it generates a magnetic field through its core. That's one magnet.

483
00:25:06,200 --> 00:25:09,320
Speaker 1: If you add a chunk of iron, then your electromagnet

484
00:25:09,359 --> 00:25:12,639
Speaker 1: will align, will magnetize your iron for you. So now

485
00:25:12,640 --> 00:25:15,760
Speaker 1: you have a permanent magnet adding to your electromagnet. So

486
00:25:15,800 --> 00:25:19,120
Speaker 1: it just adds up. So you use the electromagnet to

487
00:25:19,160 --> 00:25:22,440
Speaker 1: magnetize your chunk of iron to give you a permanent magnet,

488
00:25:22,640 --> 00:25:25,040
Speaker 1: and now your permanent magnet just sits there adding to

489
00:25:25,080 --> 00:25:27,600
Speaker 1: your electromagnet. If that's what you want, right. If you

490
00:25:27,640 --> 00:25:30,439
Speaker 1: want an oscillating magnetic field, then that's not what you

491
00:25:30,480 --> 00:25:32,800
Speaker 1: want because you can't turn off the permanent magnet or

492
00:25:32,840 --> 00:25:35,919
Speaker 1: oscillated very quickly. But if your goal is to like

493
00:25:36,240 --> 00:25:38,960
Speaker 1: be a magnet nerd and make the most powerful magnet

494
00:25:39,000 --> 00:25:41,359
Speaker 1: ever made on Earth, then that's what you want, and

495
00:25:41,400 --> 00:25:42,560
Speaker 1: that's what people are doing.

496
00:25:42,720 --> 00:25:44,720
Speaker 2: And why would you want to make the most powerful

497
00:25:44,760 --> 00:25:47,240
Speaker 2: magnet ever made on earth? Is there like a thing

498
00:25:47,320 --> 00:25:48,879
Speaker 2: you can do once you have that? Or is it

499
00:25:48,960 --> 00:25:49,520
Speaker 2: just awesome?

500
00:25:50,480 --> 00:25:52,560
Speaker 1: You get to be the magnet king or queen I mean,

501
00:25:52,600 --> 00:25:57,919
Speaker 1: come on, kell, Queen of thes, I just think it's cool.

502
00:25:58,080 --> 00:26:00,919
Speaker 1: You know, probably there will be some outplications someday, and

503
00:26:00,920 --> 00:26:03,320
Speaker 1: I hope it's not weapons. But you know, a lot

504
00:26:03,320 --> 00:26:05,639
Speaker 1: of us who got into physics just do things because like,

505
00:26:05,720 --> 00:26:08,280
Speaker 1: let's see if we can and what happens, and maybe

506
00:26:08,359 --> 00:26:11,959
Speaker 1: our theory breaks down, and you know, these things are fascinating.

507
00:26:12,119 --> 00:26:14,760
Speaker 2: Yeah, I'm fascinated. So what is the biggest magnet? Who

508
00:26:14,920 --> 00:26:18,800
Speaker 2: is the current a monarch of the magalows?

509
00:26:19,800 --> 00:26:22,440
Speaker 1: Yeah. So one of the first guys to get into

510
00:26:22,480 --> 00:26:26,760
Speaker 1: this was an American physicist named Francis Bitter. If you

511
00:26:26,760 --> 00:26:33,800
Speaker 1: look into no, and he's not a very bitter guy though.

512
00:26:33,840 --> 00:26:36,920
Speaker 1: The magnets that he inspired and he designed are called

513
00:26:36,920 --> 00:26:39,200
Speaker 1: it bitter magnets, but you know, they don't taste bitter.

514
00:26:39,359 --> 00:26:43,040
Speaker 1: Nobody's grumpy about them. They're just named after Francis Bitter. Okay,

515
00:26:43,359 --> 00:26:46,399
Speaker 1: So he and his design of magnets set a record

516
00:26:46,440 --> 00:26:50,080
Speaker 1: of forty one point four tesla, which is a huge

517
00:26:50,080 --> 00:26:53,960
Speaker 1: amount of magnetism. Right. Remember, the strongest permanent magnet ever

518
00:26:54,160 --> 00:26:57,080
Speaker 1: was like one and a half tesla, So already blowing

519
00:26:57,080 --> 00:27:00,320
Speaker 1: out of the water, all permanent magnets. The limit there

520
00:27:00,480 --> 00:27:03,119
Speaker 1: is that there's so much energy in this magnet that

521
00:27:03,200 --> 00:27:07,040
Speaker 1: basically it'll overheat. There's not a physical limit, like it's

522
00:27:07,080 --> 00:27:10,400
Speaker 1: not that you can't have more magnetism or density or something.

523
00:27:10,400 --> 00:27:14,200
Speaker 1: We think it's just that it melts the whole apparatus

524
00:27:14,240 --> 00:27:17,000
Speaker 1: because there's so much energy in it. And that's because

525
00:27:17,040 --> 00:27:19,840
Speaker 1: you know, you can't have current without loss, and the

526
00:27:19,880 --> 00:27:22,520
Speaker 1: resistance of your wire is going to heat up everything,

527
00:27:22,560 --> 00:27:25,199
Speaker 1: and you're just going to melt your whole apparatus. So

528
00:27:25,320 --> 00:27:29,000
Speaker 1: people said, well, let's try to use superconductors. Right. Superconductors

529
00:27:29,000 --> 00:27:31,840
Speaker 1: are famous for having low resistance, so higher currents, so

530
00:27:31,960 --> 00:27:35,520
Speaker 1: bigger magnet. Yeay, And that's very cool, And we use

531
00:27:35,680 --> 00:27:39,680
Speaker 1: superconducting magnets in for example, the Large Hadron Collider. Say

532
00:27:39,760 --> 00:27:42,679
Speaker 1: you wanted really powerful magnets because you wanted to bend

533
00:27:42,760 --> 00:27:45,360
Speaker 1: the path of super high energy particles so you could

534
00:27:45,400 --> 00:27:47,920
Speaker 1: collide them together and reveal the secrets of the universe. See,

535
00:27:47,960 --> 00:27:50,920
Speaker 1: there you go, there's an application for very powerful magnets.

536
00:27:51,040 --> 00:27:51,240
Speaker 6: Yay.

537
00:27:51,760 --> 00:27:53,639
Speaker 2: Why didn't you come up with that sooner? Daniel? This

538
00:27:53,840 --> 00:27:55,360
Speaker 2: is what you do, man.

539
00:27:57,359 --> 00:27:59,159
Speaker 1: I wanted to lead into it a little bit.

540
00:27:59,000 --> 00:28:02,040
Speaker 2: More you're good at this, yes, yes.

541
00:28:01,840 --> 00:28:05,240
Speaker 1: And that sounds awesome. But the problem is that superconductivity

542
00:28:05,280 --> 00:28:08,520
Speaker 1: is not something we understand super well, and at some point,

543
00:28:08,840 --> 00:28:12,280
Speaker 1: having a lot of magnetic field interferes with the superconductivity.

544
00:28:12,640 --> 00:28:16,600
Speaker 1: And the superconductivity comes from like electrons behaving weird, they

545
00:28:16,640 --> 00:28:19,760
Speaker 1: pair up with each other and flow differently, et cetera,

546
00:28:19,800 --> 00:28:22,560
Speaker 1: et cetera. It's not something we super understand, but we

547
00:28:22,600 --> 00:28:25,080
Speaker 1: do know that magnetism interferes with it. And so there's

548
00:28:25,080 --> 00:28:27,639
Speaker 1: a limit there. And they've only gotten to like thirty

549
00:28:27,640 --> 00:28:31,359
Speaker 1: two tesla at the National Magnetic Field Lab in the US.

550
00:28:31,560 --> 00:28:34,440
Speaker 2: So that's what ten tesla less than what bitter was doing,

551
00:28:34,480 --> 00:28:35,080
Speaker 2: Is that right now?

552
00:28:35,359 --> 00:28:35,600
Speaker 6: Yeah?

553
00:28:35,600 --> 00:28:38,760
Speaker 1: Exactly? Okay, yeah. So then somebody said, well, let's combine

554
00:28:38,800 --> 00:28:41,720
Speaker 1: all the best ideas out there, right, oh yeah, let's

555
00:28:41,720 --> 00:28:45,240
Speaker 1: have a bitter magnet with superconductors, and they were able

556
00:28:45,240 --> 00:28:47,440
Speaker 1: to get up to forty five tesla. This is the

557
00:28:47,440 --> 00:28:50,880
Speaker 1: Florida State Magnet Lab, and so that's the current record

558
00:28:51,160 --> 00:28:54,240
Speaker 1: for a magnet that lasts more than a few microseconds.

559
00:28:54,280 --> 00:28:56,720
Speaker 1: A magnet's like stable and you could use it to

560
00:28:56,760 --> 00:28:59,880
Speaker 1: do something, for example, But there are other folks out

561
00:28:59,880 --> 00:29:03,000
Speaker 1: there they're like, so what if your magnet milts? So

562
00:29:03,080 --> 00:29:05,080
Speaker 1: what if the whole apparatus blows up, You still got

563
00:29:05,080 --> 00:29:08,160
Speaker 1: a powerful magnet. So there are folks working on something

564
00:29:08,240 --> 00:29:11,320
Speaker 1: called explosive magnets that says like, let's just try to

565
00:29:11,320 --> 00:29:14,680
Speaker 1: get the most powerful magnetic field ever. We don't care

566
00:29:14,800 --> 00:29:17,720
Speaker 1: if the whole building collapses afterwards. We still get the record.

567
00:29:17,920 --> 00:29:20,520
Speaker 2: Okay, I mean I can get behind that attitude, But

568
00:29:20,640 --> 00:29:22,880
Speaker 2: can I take one quick step back? So yeah, I

569
00:29:23,280 --> 00:29:26,120
Speaker 2: thought that the Okay, so when we talked about using

570
00:29:26,120 --> 00:29:29,600
Speaker 2: a superconducting wire, I thought you were taking the bitter

571
00:29:29,720 --> 00:29:34,440
Speaker 2: magnet plan but using a superconducting wire instead. So what

572
00:29:34,480 --> 00:29:36,960
Speaker 2: does it mean to say you're doing a hybrid of

573
00:29:37,160 --> 00:29:39,200
Speaker 2: the bitter and the superconducting idea.

574
00:29:39,400 --> 00:29:41,080
Speaker 1: The answer is a little bit technical. The way a

575
00:29:41,120 --> 00:29:45,120
Speaker 1: bitter magnet works is or requires these circular plates with

576
00:29:45,360 --> 00:29:48,280
Speaker 1: insulating spacers in them, and it's not very conducive to

577
00:29:48,600 --> 00:29:52,200
Speaker 1: the superconducting setup. So people started from a different approach

578
00:29:52,480 --> 00:29:56,040
Speaker 1: using superconductors, and then later they're like, made some efforts

579
00:29:56,080 --> 00:29:58,400
Speaker 1: to try to bring these two designs together. So sort

580
00:29:58,440 --> 00:30:00,920
Speaker 1: of a compromised design, but has to do with the

581
00:30:00,960 --> 00:30:02,920
Speaker 1: detailed geometry of bitter magnets.

582
00:30:03,000 --> 00:30:05,000
Speaker 2: Awesome, Okay, thanks, Now let's blow some stuff up.

583
00:30:05,200 --> 00:30:08,479
Speaker 1: Yeah. So not only are these folks willing to let

584
00:30:08,560 --> 00:30:10,880
Speaker 1: their magnet get blown up, but they're going to literally

585
00:30:11,000 --> 00:30:14,200
Speaker 1: use explosives to generate the high magnetic field. They use

586
00:30:14,200 --> 00:30:17,480
Speaker 1: explosives to compress the whole apparatus, so you get a

587
00:30:17,560 --> 00:30:21,520
Speaker 1: higher density magnet as the explosion is happening. And the

588
00:30:21,560 --> 00:30:25,360
Speaker 1: record here is twenty eight hundred tesla. Wow, so we're

589
00:30:25,480 --> 00:30:29,959
Speaker 1: almost one hundred times what the bitter superconductor magnet at

590
00:30:30,000 --> 00:30:32,360
Speaker 1: the FSU Magnet Lab can do, but only for a

591
00:30:32,400 --> 00:30:34,520
Speaker 1: few microseconds. Still pretty awesome.

592
00:30:34,960 --> 00:30:35,160
Speaker 3: Yeah.

593
00:30:35,280 --> 00:30:36,920
Speaker 2: I can't imagine you're going to get a government to

594
00:30:36,960 --> 00:30:40,120
Speaker 2: fund an LHC that runs on explosive magnets, you know.

595
00:30:40,560 --> 00:30:42,520
Speaker 1: Oh that would be cool though, Yeah, be cool.

596
00:30:42,600 --> 00:30:45,320
Speaker 2: Every decade you get one really big batch of data

597
00:30:45,360 --> 00:30:46,520
Speaker 2: and then you got to start over again.

598
00:30:46,640 --> 00:30:49,600
Speaker 1: But before you feel too proud of humanity's achievements, let's

599
00:30:49,600 --> 00:30:52,600
Speaker 1: put it in like astronomical context. Right, twenty eight hundred

600
00:30:52,640 --> 00:30:55,640
Speaker 1: tesla is a lot bigger than the Earth's magnetic field,

601
00:30:55,680 --> 00:30:59,880
Speaker 1: which is like thirty to sixty microtesla. But a neutrons

602
00:31:00,480 --> 00:31:03,080
Speaker 1: is already at a million tesla. Oh wow, right, so

603
00:31:03,120 --> 00:31:07,280
Speaker 1: we're talking a thousand times are explosive magnets and a magnetar,

604
00:31:07,760 --> 00:31:11,200
Speaker 1: a super magnetized version of a neutron star that's a

605
00:31:11,240 --> 00:31:15,680
Speaker 1: pulsar and spinning and crazy, has ten to the eleven tesla,

606
00:31:16,320 --> 00:31:18,760
Speaker 1: So like blowing us out of the water by a

607
00:31:18,800 --> 00:31:21,960
Speaker 1: factor of ten to eight. So yet nature can do

608
00:31:22,000 --> 00:31:23,120
Speaker 1: what humanity can't.

609
00:31:23,280 --> 00:31:26,800
Speaker 2: Still, all right, well, so I've decided instead of the magelos,

610
00:31:27,320 --> 00:31:31,080
Speaker 2: we're going to be the magnetars because that sounds way cooler.

611
00:31:31,320 --> 00:31:34,760
Speaker 2: I'm sorry to the juggalos out there, but the magnetars

612
00:31:34,960 --> 00:31:35,840
Speaker 2: are going to.

613
00:31:35,800 --> 00:31:37,920
Speaker 1: Take over the world, all right. And so that's the

614
00:31:37,960 --> 00:31:40,600
Speaker 1: basics of how magnets work. We got permanent magnets, we

615
00:31:40,640 --> 00:31:46,120
Speaker 1: look got electromagnets. We've got magnetism generated by charges in motion.

616
00:31:46,800 --> 00:31:49,360
Speaker 1: One of the other questions that the listeners asked was

617
00:31:49,560 --> 00:31:53,160
Speaker 1: why are there no monopoles? Why do we only generate

618
00:31:53,280 --> 00:31:56,280
Speaker 1: magnetic fields from dipoles? And we talked about this a

619
00:31:56,280 --> 00:31:57,760
Speaker 1: little bit, but I want to dig a little bit

620
00:31:57,800 --> 00:32:01,120
Speaker 1: deeper into it because I want to explain why physics

621
00:32:01,280 --> 00:32:03,240
Speaker 1: wants monopoles to exist.

622
00:32:03,320 --> 00:32:05,360
Speaker 2: All right, let's see how many different ways there are

623
00:32:05,400 --> 00:32:06,640
Speaker 2: to say we don't know.

624
00:32:11,840 --> 00:32:13,960
Speaker 1: I mean, if you just looked at the equations, if

625
00:32:14,000 --> 00:32:17,120
Speaker 1: you write down Maxwell's equations, you see they describe how

626
00:32:17,160 --> 00:32:20,320
Speaker 1: electric fields are generated from sources you know, positive and

627
00:32:20,360 --> 00:32:24,720
Speaker 1: negative charges, how magnetic fields are generated from those sources

628
00:32:24,720 --> 00:32:28,719
Speaker 1: in motion, how you can even get current from magnets,

629
00:32:28,760 --> 00:32:31,200
Speaker 1: all sorts of back and forth. It's beautiful. The symmetry

630
00:32:31,240 --> 00:32:34,120
Speaker 1: is gorgeous. But there is one flaw in it, this

631
00:32:34,360 --> 00:32:37,680
Speaker 1: one glaring omission, this lack of symmetry, which is that

632
00:32:37,720 --> 00:32:40,840
Speaker 1: there are no sources of magnetic fields. And so in

633
00:32:40,880 --> 00:32:44,200
Speaker 1: the equations we just say zero, right, the total sources

634
00:32:44,240 --> 00:32:46,880
Speaker 1: of magnetic fields are zero. It would be so much

635
00:32:47,000 --> 00:32:50,120
Speaker 1: nicer if we could replace that zero with something that

636
00:32:50,320 --> 00:32:54,080
Speaker 1: paralleled what happens in electricity, where you have monopoles, you

637
00:32:54,120 --> 00:32:58,240
Speaker 1: have sources of fields. And so that awkwardness makes physicists

638
00:32:58,240 --> 00:33:00,239
Speaker 1: want to be like, well, what if there are our

639
00:33:00,240 --> 00:33:03,280
Speaker 1: poles out there, we just haven't found them yet, you know,

640
00:33:03,280 --> 00:33:05,560
Speaker 1: because that would make the equations more beautiful. And let

641
00:33:05,560 --> 00:33:08,640
Speaker 1: me remind you that beauty and symmetry in physics has

642
00:33:08,760 --> 00:33:11,880
Speaker 1: led us to real discoveries before, Like even in this

643
00:33:11,920 --> 00:33:15,320
Speaker 1: particular aspect. When Maxwell was putting his equations together, he

644
00:33:15,560 --> 00:33:17,840
Speaker 1: noticed that there was a term that was asymmetric. He

645
00:33:17,920 --> 00:33:20,360
Speaker 1: was like, hmm, it would be more beautiful if this

646
00:33:20,440 --> 00:33:22,280
Speaker 1: other term existed, And then he went out there and

647
00:33:22,320 --> 00:33:24,400
Speaker 1: actually found the effect. He's like, oh, this is a

648
00:33:24,400 --> 00:33:27,200
Speaker 1: real thing in the universe, just nobody has isolated it

649
00:33:27,200 --> 00:33:30,400
Speaker 1: and looked for it before. So symmetry does lead to

650
00:33:30,440 --> 00:33:35,160
Speaker 1: discoveries like mathematical insight really does reveal physical nature of

651
00:33:35,160 --> 00:33:38,440
Speaker 1: the universe, which is like cool and philosophical and tells

652
00:33:38,480 --> 00:33:41,800
Speaker 1: you like, wow, maybe the universe really is mathematical, and

653
00:33:41,840 --> 00:33:44,480
Speaker 1: so it inspires us. It says, hmm, wouldn't it be

654
00:33:44,520 --> 00:33:47,120
Speaker 1: cool if there was a full symmetry if these equations

655
00:33:47,200 --> 00:33:51,280
Speaker 1: really were exactly the same for electricity and magnetism. Because remember,

656
00:33:51,600 --> 00:33:54,760
Speaker 1: electricity and magnetism are not separate things. They are two

657
00:33:54,880 --> 00:33:57,760
Speaker 1: sides of the same coin. It's not even always possible

658
00:33:57,960 --> 00:34:00,000
Speaker 1: to draw a dotted line and say this is magnetic

659
00:34:00,680 --> 00:34:04,040
Speaker 1: and this is electricity. Like let's say, for example, I'm

660
00:34:04,120 --> 00:34:07,680
Speaker 1: holding an electron. I see an electric field, right, I

661
00:34:07,720 --> 00:34:09,960
Speaker 1: don't see any magnetic field because I'm just holding it.

662
00:34:09,960 --> 00:34:13,400
Speaker 1: It's not moving. But what if Kelly drives by, you know,

663
00:34:13,640 --> 00:34:16,200
Speaker 1: at fifty miles an hour, she looks at my electron.

664
00:34:16,280 --> 00:34:19,160
Speaker 1: She's like, no, that electron is moving because according to you,

665
00:34:19,280 --> 00:34:21,000
Speaker 1: it's moving a fifty miles an hour. So do you

666
00:34:21,040 --> 00:34:24,439
Speaker 1: see a magnetic field? Answer is yes, So you see

667
00:34:24,440 --> 00:34:30,439
Speaker 1: a magnetic field and I don't because really it's just electromagnetism. Right.

668
00:34:30,480 --> 00:34:33,279
Speaker 1: This dotted line we draw between them is an artifact

669
00:34:33,520 --> 00:34:37,680
Speaker 1: of humans being like, oh, electricity is lightning, magnets are

670
00:34:37,719 --> 00:34:40,760
Speaker 1: weird rocks. These are separate things, and later we realize

671
00:34:40,800 --> 00:34:43,879
Speaker 1: they're actually just two sides of the same coin. So

672
00:34:44,000 --> 00:34:46,439
Speaker 1: it would be beautiful if you could fully unify these things,

673
00:34:46,440 --> 00:34:47,640
Speaker 1: if we saw monopoles.

674
00:34:48,200 --> 00:34:50,840
Speaker 2: Every time I talk about beauty and symmetry and physics,

675
00:34:50,880 --> 00:34:54,319
Speaker 2: I find myself really wanting a framework for when we

676
00:34:54,360 --> 00:34:56,680
Speaker 2: should be able to say, oh, it would be beautiful

677
00:34:56,760 --> 00:34:59,680
Speaker 2: if there were this other thing to complete the symmetry.

678
00:35:00,120 --> 00:35:02,200
Speaker 2: And then whenever we don't see a symmetry, is that

679
00:35:02,239 --> 00:35:04,680
Speaker 2: because we're missing something or is it just like, well, there,

680
00:35:05,080 --> 00:35:08,440
Speaker 2: it just isn't symmetrical. Like when should you see symmetry

681
00:35:08,440 --> 00:35:09,239
Speaker 2: and when should you not?

682
00:35:09,880 --> 00:35:13,360
Speaker 1: We don't know, and it sounds arbitrary and biased, and

683
00:35:13,400 --> 00:35:16,400
Speaker 1: the only real explanation, if I want to be honest,

684
00:35:16,560 --> 00:35:20,120
Speaker 1: is so far this works. Like looking for symmetry and

685
00:35:20,200 --> 00:35:23,320
Speaker 1: trusting our gut about like what is beautiful and elegant

686
00:35:23,680 --> 00:35:26,319
Speaker 1: has led us to discoveries. That doesn't mean it always will.

687
00:35:26,640 --> 00:35:29,120
Speaker 1: The universe could be a mess, you know, it could

688
00:35:29,160 --> 00:35:31,200
Speaker 1: be ugly deep down. And this is something you and

689
00:35:31,239 --> 00:35:33,800
Speaker 1: I have talked about, like why do we find vista

690
00:35:33,880 --> 00:35:36,919
Speaker 1: is beautiful? Why are flowers pretty? They're not designed for us.

691
00:35:37,880 --> 00:35:41,200
Speaker 1: This whole sense of aesthetics. It feels weird and subjective

692
00:35:41,400 --> 00:35:43,719
Speaker 1: and not scientific, And yeah, that's true, but there's a

693
00:35:43,719 --> 00:35:47,040
Speaker 1: lot of subjectivity in thinking about what to explore. In

694
00:35:47,080 --> 00:35:48,840
Speaker 1: the end, the data's got to tell you what's real.

695
00:35:49,400 --> 00:35:52,759
Speaker 1: But when you're like hunting for ideas, trusting your gut

696
00:35:52,800 --> 00:35:56,840
Speaker 1: and looking for beauty is useful. And there's another reason

697
00:35:56,880 --> 00:35:59,560
Speaker 1: why we think magnetic monopoles might exist, which is if

698
00:35:59,560 --> 00:36:04,360
Speaker 1: they did, it would instantly solve another deep question about

699
00:36:04,360 --> 00:36:08,560
Speaker 1: the universe, which is why is electric charge quantized? Like

700
00:36:09,120 --> 00:36:11,479
Speaker 1: why do we have electrons that have plus one charge

701
00:36:11,480 --> 00:36:14,200
Speaker 1: but there's no particles with like one point zero zero

702
00:36:14,239 --> 00:36:17,720
Speaker 1: four to two charge or seventy five point nine charges

703
00:36:17,840 --> 00:36:21,359
Speaker 1: that come in these increments, and quarks have one third

704
00:36:21,360 --> 00:36:24,480
Speaker 1: and two third charge, but they're still quantized. Nobody knows

705
00:36:24,520 --> 00:36:27,960
Speaker 1: the answer to this. But if there was a magnetic monopole,

706
00:36:28,000 --> 00:36:31,040
Speaker 1: even just one that existed in the universe, it would

707
00:36:31,120 --> 00:36:32,040
Speaker 1: answer this question.

708
00:36:32,400 --> 00:36:36,000
Speaker 2: WHOA, all right, this is Schrodinger's equation, right, So would

709
00:36:36,000 --> 00:36:38,160
Speaker 2: that mean that if if we found one, would that

710
00:36:38,160 --> 00:36:41,120
Speaker 2: mean his equations were wrong? Or would that complete his equations?

711
00:36:42,680 --> 00:36:46,200
Speaker 1: This has to do actually with quantization of angular momentum, right.

712
00:36:46,360 --> 00:36:49,200
Speaker 1: We know that angular momentum is quantized, and we know

713
00:36:49,239 --> 00:36:52,919
Speaker 1: this relationship between electricity and magnetism, and so it's very

714
00:36:52,960 --> 00:36:56,799
Speaker 1: easy to derive this quantization from the existence of monopoles.

715
00:36:57,320 --> 00:37:00,320
Speaker 1: It's a few steps in the equations, and so famous

716
00:37:00,360 --> 00:37:04,080
Speaker 1: physicists like Joe Polchinsky says, quote, magnetic monopoles are one

717
00:37:04,120 --> 00:37:06,800
Speaker 1: of the safest bets that one can make about physics

718
00:37:06,840 --> 00:37:09,120
Speaker 1: not yet seen, like if you had to guess about

719
00:37:09,120 --> 00:37:13,160
Speaker 1: future discoveries. A lot of physicists are confident that eventually

720
00:37:13,600 --> 00:37:15,520
Speaker 1: we will see a magnetic monopole.

721
00:37:15,600 --> 00:37:16,000
Speaker 2: Oh wow.

722
00:37:16,080 --> 00:37:18,360
Speaker 1: And it's not like we haven't looked. We've been looking

723
00:37:18,400 --> 00:37:21,680
Speaker 1: for them it's actually quite easy to see a magnetic monopole.

724
00:37:22,000 --> 00:37:23,800
Speaker 2: All right, I'm dying to know how we've been looking

725
00:37:23,800 --> 00:37:27,480
Speaker 2: for them. So let's take a break, ruminate on beauty

726
00:37:27,480 --> 00:37:29,480
Speaker 2: and what it means for our universe, and when we

727
00:37:29,520 --> 00:37:52,160
Speaker 2: come back, we'll find out how you find monopoles. All right,

728
00:37:52,200 --> 00:37:54,400
Speaker 2: you were about to tell us how we go about

729
00:37:54,440 --> 00:37:56,879
Speaker 2: looking for monopoles. So what have we done so far?

730
00:37:57,080 --> 00:37:59,880
Speaker 1: There's two categories of ways to discover monopoles. One is

731
00:38:00,080 --> 00:38:02,120
Speaker 1: try to find them already existing in the universe, and

732
00:38:02,160 --> 00:38:04,719
Speaker 1: the other is try to make some. So how do

733
00:38:04,800 --> 00:38:08,080
Speaker 1: you find a monopole? Well, let's think about early experiments

734
00:38:08,080 --> 00:38:11,360
Speaker 1: with magnets. Right. Faraday did these experiments where you had

735
00:38:11,400 --> 00:38:13,719
Speaker 1: a coil of wire and he passed a magnet through it,

736
00:38:13,760 --> 00:38:17,000
Speaker 1: and he saw that it generated a current. Right, And

737
00:38:17,040 --> 00:38:19,000
Speaker 1: but the crucial thing is all the magnets he had

738
00:38:19,080 --> 00:38:21,399
Speaker 1: had a north and a south. So he would pass

739
00:38:21,520 --> 00:38:24,160
Speaker 1: the north part through the wire and it would generate

740
00:38:24,160 --> 00:38:26,359
Speaker 1: a current one way, and a south part would then

741
00:38:26,400 --> 00:38:28,359
Speaker 1: follow and it would generate a current the other way.

742
00:38:28,840 --> 00:38:30,239
Speaker 1: So if you have a dipole that goes through a

743
00:38:30,239 --> 00:38:32,000
Speaker 1: loop of wire, you get current one way and then

744
00:38:32,040 --> 00:38:33,800
Speaker 1: current the other way. It all adds up to zero

745
00:38:34,080 --> 00:38:37,080
Speaker 1: because the dipole has no net magnetic charge. But if

746
00:38:37,080 --> 00:38:39,680
Speaker 1: you have a monopole that passes through, it just generates

747
00:38:39,719 --> 00:38:42,359
Speaker 1: current in one direction. That's it. So what do you do.

748
00:38:42,600 --> 00:38:45,520
Speaker 1: You build a huge loop of current to capture any

749
00:38:45,600 --> 00:38:48,480
Speaker 1: monopole that happened to fly through, and you wait and

750
00:38:48,520 --> 00:38:52,520
Speaker 1: you just see, maybe we'll find one. And some guy

751
00:38:52,600 --> 00:38:54,400
Speaker 1: built a really big wire and he ran it for

752
00:38:54,440 --> 00:38:57,359
Speaker 1: a while. And there was this event on Valentine's Day

753
00:38:57,480 --> 00:39:00,520
Speaker 1: nineteen eighty two where he saw a huge bike a

754
00:39:00,640 --> 00:39:04,239
Speaker 1: current only in one direction. Boom. It looks exactly like

755
00:39:04,280 --> 00:39:07,839
Speaker 1: a monopole. But it's never been replicated. Nobody's ever seen

756
00:39:07,880 --> 00:39:13,439
Speaker 1: another one. So either monopoles are super dup or rare

757
00:39:13,480 --> 00:39:17,080
Speaker 1: in the universe, and he happened to capture one, nobody

758
00:39:17,120 --> 00:39:18,960
Speaker 1: has been able to do it since, which means they

759
00:39:19,040 --> 00:39:22,040
Speaker 1: must be super rare, or it was a glitch or

760
00:39:22,120 --> 00:39:25,359
Speaker 1: some weird error and not a real signal. Nobody knows

761
00:39:25,400 --> 00:39:27,680
Speaker 1: to this day, Like did he really see a monopole?

762
00:39:28,040 --> 00:39:31,680
Speaker 1: You can't really conclude yes based on just one observation, So.

763
00:39:31,800 --> 00:39:35,840
Speaker 2: Is like essentially this experiment running continuously looking for so

764
00:39:35,920 --> 00:39:38,400
Speaker 2: we're it's still running, still looking, and it's only been

765
00:39:38,440 --> 00:39:41,600
Speaker 2: seen once in forty years.

766
00:39:41,920 --> 00:39:42,840
Speaker 1: Yeah, exactly.

767
00:39:43,239 --> 00:39:43,520
Speaker 2: Wow.

768
00:39:43,600 --> 00:39:46,640
Speaker 1: And so if he's right, it means that monopoles are

769
00:39:46,719 --> 00:39:49,960
Speaker 1: like very rare, Like there's less than one monopole per

770
00:39:50,239 --> 00:39:54,000
Speaker 1: ten to the thirty atoms, which you know that's not

771
00:39:54,120 --> 00:39:55,960
Speaker 1: actually that rare, because there's a lot of ten to

772
00:39:55,960 --> 00:39:58,680
Speaker 1: the thirty atoms in the Earth, for example. But you know,

773
00:39:58,880 --> 00:40:01,400
Speaker 1: if monopoles are out there, they're super duper rare. So

774
00:40:01,520 --> 00:40:03,200
Speaker 1: the other thing we try to do is let's make them.

775
00:40:03,640 --> 00:40:06,000
Speaker 1: One thing we can do with colliders is create new

776
00:40:06,080 --> 00:40:09,280
Speaker 1: kinds of matter that we don't have ways to build otherwise.

777
00:40:09,320 --> 00:40:12,360
Speaker 1: You know, we smash protons together, it turns into some

778
00:40:12,400 --> 00:40:15,720
Speaker 1: intermediate state, and then through alchemy basically we can create

779
00:40:15,760 --> 00:40:18,120
Speaker 1: new kinds of matter. We create electrons or muons or

780
00:40:18,160 --> 00:40:21,359
Speaker 1: quarks or whatever. And so people have tried to make

781
00:40:21,480 --> 00:40:24,680
Speaker 1: magnetic monopoles at the collider. It's nothing you do in particular.

782
00:40:24,800 --> 00:40:27,320
Speaker 1: You just look to see, Hey, if we smash protons

783
00:40:27,320 --> 00:40:29,719
Speaker 1: together often enough, do any of these guys come out,

784
00:40:30,239 --> 00:40:32,959
Speaker 1: And so far we haven't seen any. They would act

785
00:40:33,000 --> 00:40:36,160
Speaker 1: weird in the magnetic fields that our detectors are immersed

786
00:40:36,160 --> 00:40:38,360
Speaker 1: in and so there would be a very obvious signal,

787
00:40:38,680 --> 00:40:40,319
Speaker 1: but we've never seen one so far.

788
00:40:40,640 --> 00:40:42,399
Speaker 2: How long have we been using this method to look

789
00:40:42,400 --> 00:40:43,080
Speaker 2: for monopoles.

790
00:40:43,400 --> 00:40:45,799
Speaker 1: Basically, every time we run a collider, we look through

791
00:40:45,800 --> 00:40:48,680
Speaker 1: the data for monopoles, and we've been doing collisions for

792
00:40:48,719 --> 00:40:51,960
Speaker 1: fifty years or so. Basically at this level, we look

793
00:40:52,000 --> 00:40:53,680
Speaker 1: for them at the large hadron collider, we look for

794
00:40:53,719 --> 00:40:55,279
Speaker 1: them at the tempatron, we look for them at the

795
00:40:55,360 --> 00:40:58,840
Speaker 1: large electron proton collider. We've never seen anything that looks

796
00:40:58,880 --> 00:41:02,919
Speaker 1: like a monopole. So that's disappointing and it's confusing because boy,

797
00:41:03,040 --> 00:41:06,040
Speaker 1: sure would be beautiful if monopoles existed, and it would

798
00:41:06,040 --> 00:41:08,440
Speaker 1: be an amazing discovery, but we've never seen one, and

799
00:41:08,480 --> 00:41:11,880
Speaker 1: so maybe the universe just is asymmetric in this way.

800
00:41:12,040 --> 00:41:14,200
Speaker 2: So, say you do see a monopole, but it really

801
00:41:14,280 --> 00:41:16,799
Speaker 2: is so rare that you see it, you know, one

802
00:41:16,920 --> 00:41:21,440
Speaker 2: time every forty five years. Is that still as amazing

803
00:41:21,480 --> 00:41:24,000
Speaker 2: If it's just this rare blip that sometimes happens in

804
00:41:24,040 --> 00:41:25,080
Speaker 2: the universe.

805
00:41:24,960 --> 00:41:29,160
Speaker 1: It's still as amazing because their very existence would be satisfactory.

806
00:41:29,280 --> 00:41:31,719
Speaker 1: It would open up new questions like, well, why are

807
00:41:31,760 --> 00:41:35,960
Speaker 1: electric monopoles everywhere and magnetic monopoles super duper rare. That

808
00:41:36,000 --> 00:41:38,680
Speaker 1: would need to answer the same way that, like matter

809
00:41:38,800 --> 00:41:41,120
Speaker 1: is everywhere and antimatter is super duper rare. That would

810
00:41:41,160 --> 00:41:43,799
Speaker 1: be another asymmetry we'd have to explain. But if they

811
00:41:43,840 --> 00:41:46,799
Speaker 1: did exist, it would be a very different universe than

812
00:41:46,840 --> 00:41:49,279
Speaker 1: one in which they were prohibited and which they just

813
00:41:49,400 --> 00:41:52,040
Speaker 1: cannot exist for some reason we don't yet know.

814
00:41:52,440 --> 00:41:57,279
Speaker 2: Well, my favorite dipole is Earth. I'm a big fan

815
00:41:57,440 --> 00:42:01,799
Speaker 2: biased Yeah, well so, yeah, that's fine. You can check

816
00:42:01,800 --> 00:42:04,080
Speaker 2: out my whole book for why I think the Earth

817
00:42:04,160 --> 00:42:07,919
Speaker 2: is so great? So why is Earth such? What makes

818
00:42:07,960 --> 00:42:09,560
Speaker 2: Earth such a great dipole? Daniel?

819
00:42:09,760 --> 00:42:11,080
Speaker 1: Is that why you don't want to go to Mars

820
00:42:11,160 --> 00:42:13,279
Speaker 1: because there's no magnetic field there and you just pro

821
00:42:13,440 --> 00:42:14,440
Speaker 1: Earth's magnetic field?

822
00:42:14,520 --> 00:42:16,440
Speaker 2: Yeah, I mean I don't think the magnetars and I

823
00:42:16,480 --> 00:42:19,040
Speaker 2: would feel really comfortable on Mars. You know, we need

824
00:42:19,080 --> 00:42:20,240
Speaker 2: a strong diepole.

825
00:42:21,680 --> 00:42:24,040
Speaker 1: Well, the Earth has a big magnetic field. We all

826
00:42:24,080 --> 00:42:26,640
Speaker 1: know that because we use compasses to navigated for thousands

827
00:42:26,680 --> 00:42:29,359
Speaker 1: of years. It's not a permanent magnet, right, It's not

828
00:42:29,400 --> 00:42:31,279
Speaker 1: just like there's a hunk of iron down there that

829
00:42:31,320 --> 00:42:34,200
Speaker 1: has a magnet to it because it's changing, right, the

830
00:42:34,200 --> 00:42:38,120
Speaker 1: Earth's magnetic field is not constant. We don't fully understand

831
00:42:38,200 --> 00:42:41,239
Speaker 1: where the Earth's magnetic field comes from. Roughly, we know

832
00:42:41,280 --> 00:42:44,520
Speaker 1: that the Earth has a fluid layer. There's rock down

833
00:42:44,560 --> 00:42:47,080
Speaker 1: there that's under a lot of pressure, and there's convection,

834
00:42:47,280 --> 00:42:49,760
Speaker 1: so the stuff is bubbling and rising and then sinking.

835
00:42:50,200 --> 00:42:53,080
Speaker 1: So you get these like loops of stuff moving and

836
00:42:53,120 --> 00:42:56,960
Speaker 1: the Earth is spinning, and so Roughly, probably the explanation

837
00:42:57,080 --> 00:43:00,080
Speaker 1: is that molten liquid currents of this stuff that and

838
00:43:00,080 --> 00:43:02,600
Speaker 1: it's charged. These are metals, a lot of them give

839
00:43:02,640 --> 00:43:05,800
Speaker 1: a magnetic field. And once you have a magnetic field,

840
00:43:06,040 --> 00:43:08,680
Speaker 1: that magnetic field can drive currents, and those currents can

841
00:43:08,719 --> 00:43:11,320
Speaker 1: make more field, and those fields make more currents. You

842
00:43:11,400 --> 00:43:15,880
Speaker 1: get this dynamo effect that enhances itself. But what we

843
00:43:15,960 --> 00:43:18,200
Speaker 1: know is that this is not something that's just fixed.

844
00:43:18,239 --> 00:43:19,880
Speaker 1: It's not like the Earth has how the same magnetic

845
00:43:19,880 --> 00:43:22,800
Speaker 1: fields for four billion years. It changes and it changes

846
00:43:22,840 --> 00:43:24,000
Speaker 1: in weird ways.

847
00:43:24,280 --> 00:43:26,799
Speaker 2: And is it changing because convection can be sort of

848
00:43:26,840 --> 00:43:30,799
Speaker 2: like random, and it's not always happening exactly the same way.

849
00:43:31,200 --> 00:43:35,040
Speaker 1: We don't know, Like we see these reversals through history

850
00:43:35,480 --> 00:43:38,799
Speaker 1: and the reversals are not periodic, like sometimes it's every

851
00:43:38,840 --> 00:43:42,680
Speaker 1: fifty million years, sometimes it's every hundred thousand years. The

852
00:43:42,719 --> 00:43:45,920
Speaker 1: most recent reversal that we've seen is about eight hundred

853
00:43:45,920 --> 00:43:49,319
Speaker 1: thousand years ago. The polls were the opposite. So like,

854
00:43:49,360 --> 00:43:52,439
Speaker 1: if you took a compass from today and went back

855
00:43:52,480 --> 00:43:55,640
Speaker 1: in time a million years, the compass would point north

856
00:43:55,640 --> 00:43:56,560
Speaker 1: towards the south pole.

857
00:43:56,719 --> 00:43:59,960
Speaker 2: What would we be totally screwed if that happens? How

858
00:44:00,000 --> 00:44:01,560
Speaker 2: how fast does it happened? Is it like, you know,

859
00:44:01,640 --> 00:44:04,359
Speaker 2: Monday morning it's one way and Monday afternoon it's the other.

860
00:44:05,120 --> 00:44:07,120
Speaker 1: No, it doesn't happen that fast, but it might be

861
00:44:07,200 --> 00:44:10,120
Speaker 1: happening right now. Like right now, the Earth's north pole

862
00:44:10,280 --> 00:44:14,200
Speaker 1: is drifting. It's moving away from the location around which

863
00:44:14,239 --> 00:44:17,080
Speaker 1: the Earth is spinning, the sort of geometric north pole

864
00:44:17,400 --> 00:44:21,879
Speaker 1: and towards Siberia at forty kilometers per year, and every

865
00:44:21,960 --> 00:44:22,960
Speaker 1: year that gets faster.

866
00:44:23,120 --> 00:44:25,960
Speaker 2: Oh yeah, so wow, are we sure it's going to

867
00:44:26,040 --> 00:44:27,799
Speaker 2: go all the way or could this just be like

868
00:44:27,880 --> 00:44:29,520
Speaker 2: a we don't know, jiggling.

869
00:44:29,640 --> 00:44:31,960
Speaker 1: It could just be a juggalo, you know, for all

870
00:44:32,040 --> 00:44:34,200
Speaker 1: we know. But the cool thing is that we can

871
00:44:34,280 --> 00:44:37,040
Speaker 1: measure the Earth's magnetic field through history. This is one

872
00:44:37,080 --> 00:44:39,600
Speaker 1: of those amazing moments when people have come up with

873
00:44:39,640 --> 00:44:44,360
Speaker 1: this incredible detective strategy to unearth some data from history.

874
00:44:45,000 --> 00:44:49,280
Speaker 1: We can use magnetized lava that's frozen on the sea floor.

875
00:44:49,600 --> 00:44:52,200
Speaker 1: What So, there's these parts of the sea where like

876
00:44:52,239 --> 00:44:54,520
Speaker 1: you're making a lot of new rock all the time.

877
00:44:54,560 --> 00:44:56,760
Speaker 1: So you're making new crust of these like mid ocean

878
00:44:56,840 --> 00:45:00,680
Speaker 1: ridges that come out and then spreads outwards, and these

879
00:45:00,760 --> 00:45:04,040
Speaker 1: are susceptible to magnetism, and so they get magnetized by

880
00:45:04,080 --> 00:45:06,960
Speaker 1: the Earth's magnetic field. All the little particles aligned in

881
00:45:07,000 --> 00:45:11,040
Speaker 1: one direction and then they freeze right, and so you

882
00:45:11,120 --> 00:45:14,239
Speaker 1: get these stripes as the Earth's magnetic field flips. This

883
00:45:14,440 --> 00:45:18,000
Speaker 1: palaeomagnetic record is formed. It's like a tape recorder of

884
00:45:18,040 --> 00:45:20,160
Speaker 1: the Earth's magnetic field. You can go down and measure

885
00:45:20,440 --> 00:45:22,359
Speaker 1: the magnetic field of this lava and you're like, oh,

886
00:45:22,400 --> 00:45:24,480
Speaker 1: it's flipped. Oh it's back. And if you know when

887
00:45:24,520 --> 00:45:26,880
Speaker 1: it was made, you can reconstruct the whole history of

888
00:45:26,920 --> 00:45:29,959
Speaker 1: the Earth's magnetic field. Isn't that amazing? Aren't scientists so clever?

889
00:45:30,239 --> 00:45:32,040
Speaker 2: That is so cool? And you know, the folks in

890
00:45:32,080 --> 00:45:35,600
Speaker 2: the geology section on our discord are rejoicing because we've

891
00:45:36,280 --> 00:45:38,880
Speaker 2: we've done something in their wheelhouse now, so yeah, that

892
00:45:39,040 --> 00:45:39,759
Speaker 2: is incredible.

893
00:45:40,040 --> 00:45:42,000
Speaker 1: Yeah, so we know that it's happening, We know that

894
00:45:42,000 --> 00:45:45,720
Speaker 1: it's irregular. We don't know why. And in contrast, for example,

895
00:45:45,960 --> 00:45:49,600
Speaker 1: the Sun has a magnetic field that flips every eleven years,

896
00:45:49,640 --> 00:45:53,919
Speaker 1: super regularly, like every eleven years for like a long

897
00:45:54,000 --> 00:45:57,399
Speaker 1: long time. Why does the Earth have a magnetic field

898
00:45:57,440 --> 00:46:00,160
Speaker 1: that flips irregularly? We don't know. Why does the Sun

899
00:46:00,239 --> 00:46:03,000
Speaker 1: or versus field ever eleven years? We don't know. We

900
00:46:03,040 --> 00:46:06,440
Speaker 1: think the Sun's magnetic field comes from connection of plasma

901
00:46:06,480 --> 00:46:10,400
Speaker 1: inside it. We don't fully understand it. Huge question. You know.

902
00:46:10,520 --> 00:46:13,720
Speaker 1: Mars we think has no magnetic field because it's essentially frozen.

903
00:46:13,760 --> 00:46:16,640
Speaker 1: There might be some motion inside Mars, but there's no

904
00:46:16,800 --> 00:46:20,520
Speaker 1: dynamo inside Mars. Venus has no field, Jupiter has a

905
00:46:20,600 --> 00:46:23,640
Speaker 1: huge field. Some moons have magnetic fields if we think

906
00:46:23,640 --> 00:46:26,560
Speaker 1: they have internal motion. So there's some understanding of a

907
00:46:26,880 --> 00:46:31,160
Speaker 1: lot of big questions left about planetary and lunar magnetic fields.

908
00:46:31,360 --> 00:46:35,640
Speaker 2: So a little bit of magic left to demystify, all.

909
00:46:35,640 --> 00:46:38,120
Speaker 1: Right, Kelly, So are magnetic fields still magic to you?

910
00:46:38,640 --> 00:46:38,840
Speaker 3: You know?

911
00:46:38,920 --> 00:46:41,400
Speaker 2: I still feel like science holds a lot of magic

912
00:46:41,440 --> 00:46:43,239
Speaker 2: in a good way, Like it's amazing that we've been

913
00:46:43,239 --> 00:46:46,320
Speaker 2: able to figure this all out. And maybe I'm stretching

914
00:46:46,360 --> 00:46:51,200
Speaker 2: the definition of magic, but I still feel I still

915
00:46:51,239 --> 00:46:54,480
Speaker 2: feel inspired and uplifted, and I get that sort of

916
00:46:54,520 --> 00:46:57,480
Speaker 2: like magical tingly feeling what I learned about some of

917
00:46:57,520 --> 00:46:59,279
Speaker 2: this stuff and the fact that we figured it all out.

918
00:46:59,600 --> 00:47:03,120
Speaker 1: Yeah, I think it's satisfying to replace the mystery with understanding.

919
00:47:03,200 --> 00:47:06,120
Speaker 1: It's not magic in the same way, but its scratches

920
00:47:06,120 --> 00:47:07,680
Speaker 1: a deep bitch for me.

921
00:47:07,680 --> 00:47:07,960
Speaker 6: Me too.

922
00:47:08,000 --> 00:47:10,080
Speaker 2: I think if I said this to my daughter, she'd

923
00:47:10,120 --> 00:47:14,400
Speaker 2: be like, come on, mom. But I still feel that

924
00:47:14,480 --> 00:47:17,200
Speaker 2: in my bone. So let's go with it, all right.

925
00:47:17,200 --> 00:47:19,120
Speaker 1: Well, thanks to everyone for writing in with your questions

926
00:47:19,160 --> 00:47:22,719
Speaker 1: about magnetism, and stay tuned for new episodes.

927
00:47:22,880 --> 00:47:34,400
Speaker 2: Thanks Meglow's Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio.

928
00:47:34,600 --> 00:47:37,280
Speaker 2: We would love to hear from you, We really would.

929
00:47:37,440 --> 00:47:40,200
Speaker 1: We want to know what questions you have about this

930
00:47:40,400 --> 00:47:42,040
Speaker 1: Extraordinary Universe.

931
00:47:42,120 --> 00:47:45,080
Speaker 2: We want to know your thoughts on recent shows, suggestions

932
00:47:45,080 --> 00:47:48,080
Speaker 2: for future shows. If you contact us, we will get

933
00:47:48,120 --> 00:47:48,520
Speaker 2: back to you.

934
00:47:48,800 --> 00:47:52,319
Speaker 1: We really mean it. We answer every message, email us

935
00:47:52,360 --> 00:47:55,560
Speaker 1: at Questions at Danielankelly.

936
00:47:54,640 --> 00:47:56,720
Speaker 2: Dot org, or you can find us on social media.

937
00:47:56,800 --> 00:48:00,600
Speaker 2: We have accounts on x, Instagram, Blue Scott and on

938
00:48:00,680 --> 00:48:02,680
Speaker 2: all of those platforms. You can find us at D

939
00:48:03,080 --> 00:48:04,600
Speaker 2: and K Universe.

940
00:48:04,800 --> 00:48:06,359
Speaker 1: Don't be shy write to us