1
00:00:08,760 --> 00:00:10,480
Speaker 1: Or Hey, did you have a good snack before you

2
00:00:10,520 --> 00:00:13,440
Speaker 1: just hit record? I did. I just finished the banana, actually,

3
00:00:13,640 --> 00:00:16,479
Speaker 1: And is that banana enough energy to power you for

4
00:00:16,520 --> 00:00:19,000
Speaker 1: a whole hour? Depends on what I'm doing that hour.

5
00:00:19,200 --> 00:00:23,880
Speaker 1: You know, procrastination doesn't take much energy. Well, it's amazing

6
00:00:23,920 --> 00:00:27,480
Speaker 1: to me that you can turn bananas into physics podcasts.

7
00:00:28,080 --> 00:00:30,880
Speaker 1: That amazes you as a physicist. Isn't all energy conserved?

8
00:00:31,000 --> 00:00:33,800
Speaker 1: Shouldn't be possible from a physics point of view? Yeah,

9
00:00:33,840 --> 00:00:36,720
Speaker 1: it might even be possible to do the opposite, right,

10
00:00:36,800 --> 00:00:43,239
Speaker 1: to turn physics podcasts back into bananas. What wouldn't that

11
00:00:43,479 --> 00:00:46,479
Speaker 1: violate the laws I don't know of physics, because imagine

12
00:00:46,479 --> 00:00:48,680
Speaker 1: all those thousands of people out there with this podcast

13
00:00:48,920 --> 00:00:52,400
Speaker 1: turning this into a banana. There must be some loss, though,

14
00:00:52,560 --> 00:00:54,280
Speaker 1: I think they would end up with a smaller banana

15
00:00:54,320 --> 00:00:57,880
Speaker 1: than the when you started with, or overly ripe banana.

16
00:00:57,920 --> 00:01:00,920
Speaker 1: Maybe that's a good way to describe podcast. Maybe you

17
00:01:00,960 --> 00:01:03,400
Speaker 1: can think of I heart media is basically amplifying your

18
00:01:03,400 --> 00:01:06,440
Speaker 1: original banana. That's bananas, Daniel. At least you're feeding your

19
00:01:06,480 --> 00:01:24,039
Speaker 1: mind as well as your body. I am more handmade

20
00:01:24,000 --> 00:01:27,000
Speaker 1: cartoonists and the creator of PhD comics. Hi, I'm Daniel.

21
00:01:27,040 --> 00:01:30,479
Speaker 1: I'm a particle of physicist and a professor at UC Irvine,

22
00:01:30,840 --> 00:01:35,320
Speaker 1: and I am sending you all physics energy, physics vise

23
00:01:36,240 --> 00:01:39,559
Speaker 1: or knowledge is knowledge energy? Daniel, there's a question about

24
00:01:39,560 --> 00:01:43,600
Speaker 1: whether information has mass. So if it does, the information

25
00:01:43,640 --> 00:01:46,560
Speaker 1: would have energy and knowledge is information, So in some

26
00:01:46,640 --> 00:01:49,480
Speaker 1: weird theories of the universe, maybe it does. Wait what

27
00:01:49,760 --> 00:01:53,840
Speaker 1: information might have mass? So all those people listening to this,

28
00:01:54,080 --> 00:01:57,640
Speaker 1: we're increasing their mass only if we actually put some

29
00:01:57,720 --> 00:02:02,200
Speaker 1: information into this podcast. So far, it's just banana jokes,

30
00:02:02,880 --> 00:02:06,240
Speaker 1: basic cholesterol. You know, there's good information and there's bad information.

31
00:02:06,480 --> 00:02:10,839
Speaker 1: Which one is healthier for you? Scientists are still debating it. Yeah,

32
00:02:11,080 --> 00:02:14,240
Speaker 1: stay tuned as they gather more information to answer this question.

33
00:02:14,520 --> 00:02:17,040
Speaker 1: But anyways, welcome to our podcast, Daniel and Jorge Explain

34
00:02:17,120 --> 00:02:19,680
Speaker 1: the Universe, a production of I Heart Radio in which

35
00:02:19,760 --> 00:02:23,320
Speaker 1: we try to sift through all the information humanity has

36
00:02:23,360 --> 00:02:27,240
Speaker 1: gathered about the crazy universe that's out there. We try

37
00:02:27,320 --> 00:02:30,840
Speaker 1: to systematize, we tried to organize, We tried to educate

38
00:02:30,880 --> 00:02:33,000
Speaker 1: you on what we do know and what we don't

39
00:02:33,040 --> 00:02:37,080
Speaker 1: know about this crazy universe, how it works, how things

40
00:02:37,160 --> 00:02:40,240
Speaker 1: slosh and flow around, how it comes together to make

41
00:02:40,280 --> 00:02:44,320
Speaker 1: this incredible, beautiful and dangerous universe that we all love. Wait,

42
00:02:44,320 --> 00:02:46,280
Speaker 1: are you saying that our job here is to take

43
00:02:46,520 --> 00:02:49,560
Speaker 1: everything that's beautiful in the universe, chew it up, eat it,

44
00:02:49,639 --> 00:02:54,239
Speaker 1: and then regurgitated back to people as information edible information.

45
00:02:54,400 --> 00:02:56,480
Speaker 1: I'm not sure which side it comes out, but yeah,

46
00:02:56,600 --> 00:03:02,320
Speaker 1: we consume it and then produce it. It's not a

47
00:03:02,320 --> 00:03:04,120
Speaker 1: pretty picture either way, is it. I like to think

48
00:03:04,160 --> 00:03:06,720
Speaker 1: of it as all part of the information food web.

49
00:03:07,080 --> 00:03:09,200
Speaker 1: You know, don't think so much about who is eating

50
00:03:09,240 --> 00:03:12,520
Speaker 1: who as much as you know information is flowing from

51
00:03:12,600 --> 00:03:19,560
Speaker 1: person to purses. We're all just stardust and predigested information. Yeah,

52
00:03:19,560 --> 00:03:22,520
Speaker 1: although maybe you are the information super predator. You're the

53
00:03:22,560 --> 00:03:28,320
Speaker 1: apex information consumer. Oh I really huh? And nobody has

54
00:03:28,360 --> 00:03:30,480
Speaker 1: ever called me the apex anything. Well, think about it.

55
00:03:30,520 --> 00:03:32,799
Speaker 1: You talked to lots of scientists, and you distill from

56
00:03:32,880 --> 00:03:36,360
Speaker 1: all of them little bits of crucial science knowledge. Wow,

57
00:03:36,640 --> 00:03:38,680
Speaker 1: maybe that's why I'm so full all the time. It's

58
00:03:38,680 --> 00:03:41,320
Speaker 1: a lot of bananas to keep that. Or you're just

59
00:03:41,360 --> 00:03:44,880
Speaker 1: consuming all those scientists brains effectively. That makes you so

60
00:03:45,120 --> 00:03:48,000
Speaker 1: like a science zombie. I'm not sure now, zombie too.

61
00:03:48,080 --> 00:03:51,560
Speaker 1: Oh my goodness. First I was regurgitating. Now I'm stumbling

62
00:03:51,560 --> 00:03:56,600
Speaker 1: around half dead. Actually that that is pretty accurate these days,

63
00:03:57,280 --> 00:03:59,080
Speaker 1: at this time in the morning. You do a good

64
00:03:59,160 --> 00:04:01,800
Speaker 1: zombie impression. Now you told me zombies don't always stumble

65
00:04:01,800 --> 00:04:04,880
Speaker 1: is sometimes zombies are fast moving and even articulate. Yeah, yeah,

66
00:04:04,920 --> 00:04:08,840
Speaker 1: it's kind of zombies. Yeah, then the new kinds of

67
00:04:08,920 --> 00:04:11,160
Speaker 1: zombies are now fast and furious. We've got a lot

68
00:04:11,160 --> 00:04:13,800
Speaker 1: of response from the Zombie Star episode, people writing in

69
00:04:13,880 --> 00:04:17,240
Speaker 1: recommending zombie movies that they thought I might enjoy. Oh good,

70
00:04:17,320 --> 00:04:20,480
Speaker 1: are you gonna watching? Do you need an honest answer

71
00:04:20,480 --> 00:04:24,599
Speaker 1: to that question? Why? Well, why not? There's too many

72
00:04:24,640 --> 00:04:27,000
Speaker 1: things out there to watch. So they're on my list,

73
00:04:27,080 --> 00:04:29,479
Speaker 1: but I might not make it. I see, that's the

74
00:04:29,520 --> 00:04:32,720
Speaker 1: political answer, got it, got it. But thank you everyone

75
00:04:32,800 --> 00:04:35,280
Speaker 1: for your suggestions. I will get to them eventually. Well

76
00:04:35,320 --> 00:04:37,960
Speaker 1: I'm curiously know what's on that list. But today we're

77
00:04:38,000 --> 00:04:40,520
Speaker 1: talking about something a little bit different than Zombie Stars.

78
00:04:40,720 --> 00:04:43,880
Speaker 1: That's right. We are venturing into the border between physics

79
00:04:43,920 --> 00:04:46,960
Speaker 1: and philosophy. We are not just trying to understand how

80
00:04:47,000 --> 00:04:49,839
Speaker 1: the universe work, We're trying to understand what it means,

81
00:04:49,960 --> 00:04:52,000
Speaker 1: because physics is more than just a list of laws.

82
00:04:52,040 --> 00:04:55,800
Speaker 1: It's an attempt to get some deep intuitive understanding into

83
00:04:55,880 --> 00:04:59,320
Speaker 1: how the universe works, to reach those ah ha moments

84
00:04:59,400 --> 00:05:02,920
Speaker 1: where you feel I get it. I understand something now

85
00:05:02,960 --> 00:05:05,200
Speaker 1: about how the universe is doing it that I didn't

86
00:05:05,279 --> 00:05:08,480
Speaker 1: understand before. Wait. Wait, wait, wait, we're going into philosophical

87
00:05:08,720 --> 00:05:12,640
Speaker 1: territory here. Can we go back to the zombies? Well,

88
00:05:12,640 --> 00:05:15,200
Speaker 1: we can talk about philosophical zombies if you like. That's

89
00:05:15,240 --> 00:05:19,040
Speaker 1: one of my favorite topics, or the philosophy of zombies.

90
00:05:19,400 --> 00:05:23,000
Speaker 1: M like, is a zombie still a person or not? No,

91
00:05:23,120 --> 00:05:26,200
Speaker 1: that's philosophy by zombies. You know, they have whole journals

92
00:05:26,600 --> 00:05:30,360
Speaker 1: that only zombies, right for Oh no, it is kind

93
00:05:30,360 --> 00:05:32,719
Speaker 1: of a half that discipline. Anyways, you know, the the

94
00:05:32,800 --> 00:05:36,359
Speaker 1: overlap between physics and philosophy is very healthy, very vibrant,

95
00:05:36,440 --> 00:05:39,600
Speaker 1: really fascinating, and for me, one of the motivating aspects

96
00:05:39,600 --> 00:05:42,560
Speaker 1: of physics. One reason we do physics is to help

97
00:05:42,640 --> 00:05:45,800
Speaker 1: answer questions, which, in the end our philosophical what does

98
00:05:45,839 --> 00:05:47,719
Speaker 1: it mean to be alive? Why are we here? What

99
00:05:47,720 --> 00:05:49,760
Speaker 1: should we do with our lives? How do we make

100
00:05:49,800 --> 00:05:52,640
Speaker 1: sense of this cosmos? Those aren't science questions, but the

101
00:05:52,680 --> 00:05:56,080
Speaker 1: answers to science questions can help us understand how to

102
00:05:56,160 --> 00:05:59,760
Speaker 1: tackle those other more difficult philosophical questions. Yeah, because I

103
00:05:59,760 --> 00:06:03,000
Speaker 1: guess it is a pretty incredible universe, and even though

104
00:06:03,040 --> 00:06:05,400
Speaker 1: we may want to understand how it all works, there's

105
00:06:05,440 --> 00:06:08,000
Speaker 1: still sort of the questions that you can ask beyond that,

106
00:06:08,120 --> 00:06:11,360
Speaker 1: beyond physics, right, like what does it mean? Or why

107
00:06:11,400 --> 00:06:13,560
Speaker 1: are we here? And some of those questions are really

108
00:06:13,600 --> 00:06:16,840
Speaker 1: simple signing questions, the kind of questions you often ask

109
00:06:16,920 --> 00:06:19,159
Speaker 1: me when I start talking about something complicated and you're like,

110
00:06:19,200 --> 00:06:21,839
Speaker 1: hold on, back up, what are we even talking about?

111
00:06:21,920 --> 00:06:25,599
Speaker 1: Can you give me a definition of space or mass?

112
00:06:26,000 --> 00:06:28,400
Speaker 1: What are these things we're talking about? Do we really

113
00:06:28,520 --> 00:06:30,880
Speaker 1: understand them? Yeah, because I guess you know, you grew

114
00:06:30,960 --> 00:06:33,000
Speaker 1: up in this universe and maybe you become a physicist

115
00:06:33,120 --> 00:06:35,680
Speaker 1: or not, but you still kind of study it, and you,

116
00:06:35,680 --> 00:06:37,360
Speaker 1: you know, you start to take things a little bit

117
00:06:37,360 --> 00:06:39,320
Speaker 1: for granted, you know, in a way, you know, you know,

118
00:06:39,360 --> 00:06:41,919
Speaker 1: we think about the fact that we walk around on

119
00:06:42,000 --> 00:06:43,880
Speaker 1: this planet, but why are we stuck to this planet

120
00:06:43,880 --> 00:06:45,839
Speaker 1: at all and not floating out there in space. Yeah,

121
00:06:45,880 --> 00:06:47,920
Speaker 1: it's a really important exercise to take a step back

122
00:06:47,960 --> 00:06:50,240
Speaker 1: and say, what is this thing we're talking about, What

123
00:06:50,279 --> 00:06:52,120
Speaker 1: does it really mean? What do we know about it?

124
00:06:52,360 --> 00:06:54,920
Speaker 1: What can we learn about the nature of the universe

125
00:06:55,200 --> 00:06:58,320
Speaker 1: from what we know about how these physical processes happen. Yeah,

126
00:06:58,360 --> 00:07:01,000
Speaker 1: it always amazes me that there are basic concepts and

127
00:07:01,040 --> 00:07:04,320
Speaker 1: physics that physicists don't really have a good definition for

128
00:07:04,520 --> 00:07:06,520
Speaker 1: or a good explanation for. You know, we've covered a

129
00:07:06,520 --> 00:07:08,320
Speaker 1: lot of them in our book. We have No Idea

130
00:07:08,440 --> 00:07:10,920
Speaker 1: a guide to the Unknown Universe. But it's still amazing

131
00:07:10,920 --> 00:07:12,960
Speaker 1: that there are things that even we didn't cover in

132
00:07:13,000 --> 00:07:16,320
Speaker 1: the book that physicists still struggle to define. You don't

133
00:07:16,360 --> 00:07:19,560
Speaker 1: have to know what you're talking about to sometimes accomplish

134
00:07:19,600 --> 00:07:22,520
Speaker 1: something in physics. The most famous example is quantum mechanics.

135
00:07:22,720 --> 00:07:25,160
Speaker 1: Nobody really understands what it means, but we can do

136
00:07:25,240 --> 00:07:30,040
Speaker 1: really complicated, really accurate calculations and predictions using quantum mechanics,

137
00:07:30,040 --> 00:07:33,320
Speaker 1: even if we don't quite grasp what exactly is going on. Yeah,

138
00:07:33,560 --> 00:07:36,720
Speaker 1: and maybe out of all those basic concepts about the universe,

139
00:07:36,760 --> 00:07:41,920
Speaker 1: there are maybe none more basic than the idea of energy.

140
00:07:42,160 --> 00:07:45,920
Speaker 1: That seems like a super duper basic concept in physics.

141
00:07:46,080 --> 00:07:47,600
Speaker 1: It is, in fact, and it's something a lot of

142
00:07:47,640 --> 00:07:49,800
Speaker 1: listeners over the years have written in to ask us

143
00:07:49,840 --> 00:07:51,920
Speaker 1: to talk about so to the on the podcast will

144
00:07:51,960 --> 00:08:00,680
Speaker 1: be tackling the question what is energy? And where can

145
00:08:00,720 --> 00:08:04,400
Speaker 1: we get some more of it? Yeah? That's not coming

146
00:08:04,440 --> 00:08:07,680
Speaker 1: from a coffee cup maybe or dead plants underground. But

147
00:08:07,760 --> 00:08:09,520
Speaker 1: it is kind of sort of an interesting question, I

148
00:08:09,560 --> 00:08:11,760
Speaker 1: think because it's so short, right, Like, this is one

149
00:08:11,800 --> 00:08:14,640
Speaker 1: of the shortest questions we've tackled in a long time

150
00:08:14,680 --> 00:08:17,800
Speaker 1: on this podcast. It's just three words, what is energy?

151
00:08:18,120 --> 00:08:22,040
Speaker 1: Maybe we should add a fourth one man, what is energy? Man?

152
00:08:22,600 --> 00:08:27,720
Speaker 1: What is energy? Anyway? Or maybe what? I guess we

153
00:08:27,720 --> 00:08:31,960
Speaker 1: could go deeper, we go what is Eventually we'll just

154
00:08:32,000 --> 00:08:35,280
Speaker 1: be asking the question what. Maybe that's all physics and

155
00:08:35,320 --> 00:08:39,360
Speaker 1: philosophy is just responding to the universe and going what. Yeah,

156
00:08:39,800 --> 00:08:41,760
Speaker 1: but then we will, you know, like a Marvel movie

157
00:08:41,800 --> 00:08:50,199
Speaker 1: will find another sequel. We'll go with where or Speechless

158
00:08:50,200 --> 00:08:53,040
Speaker 1: the new seel. But it is a really simple sounding

159
00:08:53,160 --> 00:08:55,840
Speaker 1: question with a lot of subtle nuances, which is why

160
00:08:55,840 --> 00:08:57,640
Speaker 1: it took us a little while to figure out how

161
00:08:57,720 --> 00:09:00,120
Speaker 1: to attack it. It's a short question without an the

162
00:09:00,240 --> 00:09:02,480
Speaker 1: simple answer. Yeah, I was thinking about this word and

163
00:09:02,600 --> 00:09:05,679
Speaker 1: it's kind of interesting. Because I think everyone you know

164
00:09:05,679 --> 00:09:08,320
Speaker 1: knows the word obviously energy and has something you know,

165
00:09:08,440 --> 00:09:11,240
Speaker 1: some some intuitous sense attached to it. But you know,

166
00:09:11,280 --> 00:09:13,160
Speaker 1: if you sort of think about what is it, it's

167
00:09:13,200 --> 00:09:15,760
Speaker 1: kind of hard to define. Yeah, you're used to talking

168
00:09:15,760 --> 00:09:17,680
Speaker 1: about it, you think about it in your life, you

169
00:09:17,800 --> 00:09:20,199
Speaker 1: pay for it, you use it. But if you sit

170
00:09:20,280 --> 00:09:22,400
Speaker 1: on your couch late at night and wonder, like, what

171
00:09:22,600 --> 00:09:24,600
Speaker 1: is it? Has seems to have so many forms, they

172
00:09:24,600 --> 00:09:26,920
Speaker 1: can transform back and forth into each other. It's a

173
00:09:27,000 --> 00:09:29,559
Speaker 1: vital part of the universe. It feels like it should

174
00:09:29,559 --> 00:09:32,400
Speaker 1: be something fundamental. But is a physical thing? Is it

175
00:09:32,520 --> 00:09:36,040
Speaker 1: just a calculation that we do? Is it a philosophical question?

176
00:09:36,440 --> 00:09:38,720
Speaker 1: It's a really hard thing to grapple with. Yeah, and

177
00:09:38,760 --> 00:09:41,320
Speaker 1: even physicists in their textbooks have sort of a hard

178
00:09:41,360 --> 00:09:43,040
Speaker 1: time pinning this down right. I mean, there is sort

179
00:09:43,040 --> 00:09:46,400
Speaker 1: of an official definition of it, right as the capacity

180
00:09:46,440 --> 00:09:49,079
Speaker 1: to do work. Yeah, there is that definition. But then

181
00:09:49,120 --> 00:09:51,640
Speaker 1: you look at the official definition of work and its

182
00:09:51,920 --> 00:09:59,560
Speaker 1: energy transfer a lot, it moves back on itself, like inception, Yeah, exactly,

183
00:09:59,720 --> 00:10:03,880
Speaker 1: deaf nisition ce definition. So energy is defined in terms

184
00:10:03,880 --> 00:10:05,839
Speaker 1: of work, and work is defined in terms of energy,

185
00:10:05,920 --> 00:10:10,520
Speaker 1: So like, what is this thing we're talking about. Wow. Interesting, Yeah,

186
00:10:10,559 --> 00:10:13,320
Speaker 1: because I guess that's the only way we know how

187
00:10:13,320 --> 00:10:16,079
Speaker 1: to define it. Kind of maybe, sort of, And you

188
00:10:16,120 --> 00:10:19,720
Speaker 1: have to grapple with the subtlety between physics definitions like

189
00:10:19,800 --> 00:10:23,600
Speaker 1: what we technically mean by work and our intuitive understanding

190
00:10:23,640 --> 00:10:27,840
Speaker 1: of these concepts, because physics often repurposes a word that

191
00:10:28,000 --> 00:10:31,280
Speaker 1: everybody uses a normal language to mean something very specific

192
00:10:31,360 --> 00:10:36,280
Speaker 1: and technical. For physics, that's true for example for work. Interesting. Well,

193
00:10:36,360 --> 00:10:38,559
Speaker 1: let's start to dig into this, but first, as usually,

194
00:10:38,640 --> 00:10:40,880
Speaker 1: we're wondering how many people out there have thought about

195
00:10:40,920 --> 00:10:43,719
Speaker 1: this very basic question and how many people out there

196
00:10:43,840 --> 00:10:46,319
Speaker 1: think they know the answer to this. So thanks very

197
00:10:46,360 --> 00:10:50,000
Speaker 1: much to everybody who volunteered to answer difficult, random questions

198
00:10:50,040 --> 00:10:53,440
Speaker 1: from an internet physicist. I really appreciate your work. And

199
00:10:53,480 --> 00:10:55,320
Speaker 1: if you're out there and have been listening to the

200
00:10:55,360 --> 00:10:58,120
Speaker 1: podcast and want to put your roove always to these questions,

201
00:10:58,160 --> 00:11:01,080
Speaker 1: please don't be shy. Send me an email two questions

202
00:11:01,120 --> 00:11:03,800
Speaker 1: at Daniel and Jorge dot com. Think about it for

203
00:11:03,800 --> 00:11:07,160
Speaker 1: a second. What do you think energy is or how

204
00:11:07,200 --> 00:11:10,400
Speaker 1: would you explain it? Here's what people had to say. Um,

205
00:11:10,400 --> 00:11:13,320
Speaker 1: I remember learning in maybe high school physics that energy

206
00:11:13,720 --> 00:11:16,920
Speaker 1: is the ability for something to do work. UM. I

207
00:11:16,960 --> 00:11:19,280
Speaker 1: think that that's probably not nuanced enough of a definition.

208
00:11:19,679 --> 00:11:22,240
Speaker 1: More nuanced way to look at it might be it's

209
00:11:22,320 --> 00:11:25,960
Speaker 1: um something's ability to affect change, which doesn't necessarily have

210
00:11:26,040 --> 00:11:29,240
Speaker 1: to be work, and sort of like the classic physics definition.

211
00:11:29,720 --> 00:11:33,760
Speaker 1: I think energy is truly just a vibration, and the

212
00:11:33,880 --> 00:11:41,160
Speaker 1: energy potential is dictated by the field the vibration or

213
00:11:41,240 --> 00:11:46,480
Speaker 1: string sits with him. I've asked this question to someone

214
00:11:46,480 --> 00:11:49,200
Speaker 1: who knew a lot about physics before, and their answer

215
00:11:49,280 --> 00:11:51,760
Speaker 1: was not useful to me. What I came away with

216
00:11:51,880 --> 00:11:55,240
Speaker 1: is like energy is potential for things to happen, and

217
00:11:55,400 --> 00:11:58,320
Speaker 1: concentrations of that potential, and it's expressed in a lot

218
00:11:58,360 --> 00:12:00,880
Speaker 1: of ways. This feels like it should be one of

219
00:12:00,880 --> 00:12:05,240
Speaker 1: those like really easy questions to answer fifth graders should

220
00:12:05,240 --> 00:12:09,160
Speaker 1: know this or something, but I'm having trouble explaining it.

221
00:12:09,160 --> 00:12:15,880
Speaker 1: It is a force like but needed to create force.

222
00:12:16,280 --> 00:12:18,000
Speaker 1: I mean, I think of going down to like the

223
00:12:18,000 --> 00:12:25,320
Speaker 1: atomic level. Energy is like the movement of electrons. Intuitively,

224
00:12:25,840 --> 00:12:30,760
Speaker 1: when I think of energy, I think about vibrating particles

225
00:12:30,320 --> 00:12:34,840
Speaker 1: and the fast of their vibrating more energy they have.

226
00:12:35,040 --> 00:12:39,640
Speaker 1: But I guess at a more fundamental level energy is

227
00:12:39,720 --> 00:12:44,840
Speaker 1: about probably fields and like how much energy is in

228
00:12:45,400 --> 00:12:49,040
Speaker 1: a certain field, dictating what kind of particle is and

229
00:12:49,240 --> 00:12:51,640
Speaker 1: what that particle is doing. I think energy is just

230
00:12:51,679 --> 00:12:55,079
Speaker 1: like tiny movement of particles that gets passed along from

231
00:12:55,080 --> 00:12:57,880
Speaker 1: particle to particle. Energy is the opposite side of the

232
00:12:57,920 --> 00:13:01,240
Speaker 1: coin is mass. But my us as you're referring to

233
00:13:01,280 --> 00:13:03,840
Speaker 1: the fundamental building blocks of energy, and I'm not sure

234
00:13:03,840 --> 00:13:07,080
Speaker 1: what those could be. All Right, interesting answers um pretty

235
00:13:07,120 --> 00:13:08,839
Speaker 1: deep ones to a lot of people are like, it's

236
00:13:08,840 --> 00:13:13,199
Speaker 1: a vibe, man, it's a mood. Yeah, And some people

237
00:13:13,240 --> 00:13:16,960
Speaker 1: giving examples of what energy is and some people talking

238
00:13:17,000 --> 00:13:19,400
Speaker 1: about the different forms of it. It's the really interesting

239
00:13:19,400 --> 00:13:22,080
Speaker 1: answers here. Thanks everyone. Yeah, and some people even sort

240
00:13:22,080 --> 00:13:24,439
Speaker 1: of went with the official definition, which is that it's

241
00:13:24,480 --> 00:13:27,520
Speaker 1: related to your ability to do work or to make

242
00:13:27,559 --> 00:13:29,880
Speaker 1: work or change work. But did did you follow up

243
00:13:29,880 --> 00:13:33,559
Speaker 1: with them? Then? What does work mean? No? I don't

244
00:13:33,559 --> 00:13:36,360
Speaker 1: actually have live conversations with these folks. It's just the email.

245
00:13:36,520 --> 00:13:38,480
Speaker 1: When I do interviews on campus, then I can ask

246
00:13:38,520 --> 00:13:41,079
Speaker 1: fun follow up questions like does that scare you? Are

247
00:13:41,120 --> 00:13:43,839
Speaker 1: you worried about that? But here I just give them

248
00:13:43,840 --> 00:13:47,679
Speaker 1: the one shot I see, I see, I see. You're

249
00:13:47,720 --> 00:13:50,800
Speaker 1: trying to still fear in them. No, I try to

250
00:13:50,840 --> 00:13:53,520
Speaker 1: be friendly and not instill fear in them over email

251
00:13:53,520 --> 00:13:55,640
Speaker 1: in person. Yeah, absolutely, I'll put them on the spot.

252
00:13:57,480 --> 00:13:59,839
Speaker 1: All right, Well, it's a tricky subject, and I think

253
00:13:59,840 --> 00:14:03,240
Speaker 1: I will find out it's something that has some deep

254
00:14:03,280 --> 00:14:07,160
Speaker 1: mysteries about it, right, It's not an easy answer answer.

255
00:14:07,360 --> 00:14:09,640
Speaker 1: All right, Well, Daniel step us through. What are some

256
00:14:09,720 --> 00:14:11,760
Speaker 1: of the first things that physicists think of when they

257
00:14:11,760 --> 00:14:14,040
Speaker 1: think of energy? So right off the bat, we should

258
00:14:14,040 --> 00:14:18,400
Speaker 1: just admit that we don't fundamentally know what energy is. Wait,

259
00:14:18,440 --> 00:14:22,520
Speaker 1: what we're done with the podcast? Nobody knows that's it.

260
00:14:24,240 --> 00:14:26,520
Speaker 1: You know some things about it, We figured some things out.

261
00:14:26,920 --> 00:14:28,720
Speaker 1: You can use those to piece together a picture of

262
00:14:28,800 --> 00:14:31,280
Speaker 1: what it might be and what that means, But fundamentally

263
00:14:31,280 --> 00:14:35,280
Speaker 1: it remains a philosophical mystery what energy is. First, maybe

264
00:14:35,320 --> 00:14:37,200
Speaker 1: I should put the question back on you and ask, like,

265
00:14:37,560 --> 00:14:40,080
Speaker 1: what kind of answer do people expect? Like what kind

266
00:14:40,080 --> 00:14:42,840
Speaker 1: of answer would be satisfying? Where is the sort of

267
00:14:43,000 --> 00:14:45,640
Speaker 1: nature of the question we're even asking? Do you want

268
00:14:45,640 --> 00:14:48,400
Speaker 1: to know if energy is like a thing that flows

269
00:14:48,520 --> 00:14:51,360
Speaker 1: or if it's made out of little energy ons? Or

270
00:14:51,520 --> 00:14:55,360
Speaker 1: just like a concise definition of what this thing is. Well,

271
00:14:55,400 --> 00:14:57,440
Speaker 1: I mean you sort of give it away. He kind

272
00:14:57,440 --> 00:15:00,320
Speaker 1: of spoiled the answer for me here and seem to

273
00:15:00,320 --> 00:15:01,960
Speaker 1: not want to try. I mean, if you guys don't

274
00:15:01,960 --> 00:15:04,960
Speaker 1: know what it is, what I know. But it's kind

275
00:15:04,960 --> 00:15:07,160
Speaker 1: of an interesting question. I think, you know, at the

276
00:15:07,240 --> 00:15:09,680
Speaker 1: base of it, I think most people think of energy

277
00:15:09,840 --> 00:15:12,880
Speaker 1: is like the opposite of of not moving, you know

278
00:15:12,920 --> 00:15:15,840
Speaker 1: what I mean, Like it's the opposite of standing still

279
00:15:15,880 --> 00:15:18,720
Speaker 1: and not doing anything. Like if you have energy, then

280
00:15:18,760 --> 00:15:21,560
Speaker 1: you're doing something, You're doing work, I guess, yeah. And

281
00:15:21,600 --> 00:15:24,680
Speaker 1: I think that a lot of the concepts about energy

282
00:15:24,800 --> 00:15:27,280
Speaker 1: start from examples. I think some of the difficulty comes

283
00:15:27,280 --> 00:15:28,800
Speaker 1: from the fact that you can put lots of different

284
00:15:28,880 --> 00:15:31,480
Speaker 1: kinds of examples together and then wonder, like what do

285
00:15:31,560 --> 00:15:34,080
Speaker 1: they all have in common? You know, the mass is

286
00:15:34,200 --> 00:15:36,000
Speaker 1: energy or this is energy, Then what do they all

287
00:15:36,080 --> 00:15:38,720
Speaker 1: have in common? And so maybe we should start with

288
00:15:38,760 --> 00:15:40,720
Speaker 1: sort of like the history of the idea of the

289
00:15:40,760 --> 00:15:44,240
Speaker 1: development of energy, how people discover different forms of energy

290
00:15:44,320 --> 00:15:47,440
Speaker 1: and then talk about the common thread between them. Yeah, yeah, sure,

291
00:15:47,520 --> 00:15:49,200
Speaker 1: well I was thinking kind of it's kind of like

292
00:15:49,200 --> 00:15:53,200
Speaker 1: maybe the opposite of the phrase nothing happens. Like if

293
00:15:53,240 --> 00:15:57,240
Speaker 1: nothing happens, ever, then there's no energy, but if things happen,

294
00:15:57,680 --> 00:16:00,440
Speaker 1: then there's energy. It's like maybe related to the word happening,

295
00:16:00,600 --> 00:16:03,000
Speaker 1: that's possibly true, but there are subtle wrinkles there, like

296
00:16:03,040 --> 00:16:05,520
Speaker 1: you can have a universe with a lot of energy

297
00:16:05,560 --> 00:16:08,880
Speaker 1: but no free energy, like the heat death of the universe.

298
00:16:08,960 --> 00:16:11,280
Speaker 1: Nothing can really happen. But there is a lot of

299
00:16:11,400 --> 00:16:14,280
Speaker 1: energy in the universe, there's just none available to do

300
00:16:14,320 --> 00:16:18,040
Speaker 1: work because there's no energy gradients. So there are different

301
00:16:18,080 --> 00:16:21,280
Speaker 1: kinds of energy, different kinds of energy. And fundamentally, the

302
00:16:21,320 --> 00:16:23,920
Speaker 1: game we're playing here is that we're looking around in

303
00:16:23,960 --> 00:16:27,240
Speaker 1: the universe and we're coming up with ways to do calculations,

304
00:16:27,280 --> 00:16:30,920
Speaker 1: and we're wondering do those mean anything? And energy in

305
00:16:30,960 --> 00:16:34,000
Speaker 1: that sense isn't like something physical. It's an observation we

306
00:16:34,080 --> 00:16:36,640
Speaker 1: make about the universe. Like I can look at a

307
00:16:36,640 --> 00:16:39,520
Speaker 1: physical system, you know, the Earth moving around the Sun,

308
00:16:40,080 --> 00:16:41,960
Speaker 1: and I can do a calculation that could say, well,

309
00:16:42,040 --> 00:16:44,440
Speaker 1: I'm going to define some quantity. I call it energy,

310
00:16:44,680 --> 00:16:47,240
Speaker 1: And here's how I calculated. I take the velocity I'm

311
00:16:47,280 --> 00:16:49,760
Speaker 1: multiplied by the mass. I add this, I add that

312
00:16:49,760 --> 00:16:52,560
Speaker 1: that's the something I invented call it energy. And most

313
00:16:52,600 --> 00:16:54,880
Speaker 1: of the time, if you just invent a quantity, it's

314
00:16:54,920 --> 00:16:57,760
Speaker 1: not interesting or useful, doesn't reveal anything about the universe.

315
00:16:58,000 --> 00:17:00,880
Speaker 1: But sometimes it does, and it was especially when it

316
00:17:00,920 --> 00:17:03,600
Speaker 1: seems like it might be conserved when you've constructed this

317
00:17:03,720 --> 00:17:07,040
Speaker 1: quantity which seems to like not change as time goes

318
00:17:07,080 --> 00:17:10,119
Speaker 1: on through the universe. Mm hmmmm. Well, that's an interesting

319
00:17:10,160 --> 00:17:12,720
Speaker 1: concept to think about. How they came up how humans

320
00:17:12,760 --> 00:17:14,320
Speaker 1: came up with the word, right, Like, did we come

321
00:17:14,359 --> 00:17:18,000
Speaker 1: up with that word for energy before science even you

322
00:17:18,040 --> 00:17:19,520
Speaker 1: know what I mean? Like that? I wonder if Caveman

323
00:17:19,880 --> 00:17:23,120
Speaker 1: had a phrase or a word for this idea of

324
00:17:23,280 --> 00:17:26,560
Speaker 1: things happening or energy. I think Caveman had teenagers, and

325
00:17:26,600 --> 00:17:28,760
Speaker 1: teenagers didn't get out of the cave very early in

326
00:17:28,800 --> 00:17:31,119
Speaker 1: the morning, and people wondered if they needed more energy.

327
00:17:31,160 --> 00:17:34,040
Speaker 1: I'm sure that you know the intuitive concept of feeling

328
00:17:34,080 --> 00:17:36,960
Speaker 1: like you have energy or you're tired. That's an age

329
00:17:37,000 --> 00:17:40,760
Speaker 1: old idea for sure. M So we probably had a

330
00:17:40,800 --> 00:17:43,520
Speaker 1: word for it, and then people started to use it

331
00:17:43,560 --> 00:17:47,320
Speaker 1: in physics. Yeah, and scientifically, one of the first concepts

332
00:17:47,320 --> 00:17:50,240
Speaker 1: that was developed was kinetic energy. So you've got to

333
00:17:50,240 --> 00:17:53,879
Speaker 1: go back to people like Leibnitz. It was Newton's contemporary

334
00:17:54,040 --> 00:17:56,960
Speaker 1: and you know, also developed calculus, and like Newton, he

335
00:17:57,000 --> 00:17:59,680
Speaker 1: also did a bit of physics, right, And the Leibnitz

336
00:17:59,720 --> 00:18:02,240
Speaker 1: note us that things moved, that there's motion. And he

337
00:18:02,280 --> 00:18:06,800
Speaker 1: came up with this quantity mass times velocity times velocity again,

338
00:18:07,000 --> 00:18:10,320
Speaker 1: so MV squared, And he said, this thing seems to

339
00:18:10,359 --> 00:18:14,199
Speaker 1: be conserved. He called this thing vis visa, like a

340
00:18:14,240 --> 00:18:18,960
Speaker 1: living force, and so he essentially stumbled across the definition

341
00:18:18,960 --> 00:18:21,600
Speaker 1: of kinetic energy and said, hey, here's a quantity which

342
00:18:21,640 --> 00:18:23,920
Speaker 1: is interesting because it seems to be conserved. It seems

343
00:18:24,040 --> 00:18:27,280
Speaker 1: like as time passes and you recalculate this quantity, it

344
00:18:27,359 --> 00:18:29,960
Speaker 1: doesn't change, right. But I guess maybe a question is

345
00:18:29,960 --> 00:18:33,200
Speaker 1: how did he noticed that it was conserved? Like why

346
00:18:33,240 --> 00:18:36,399
Speaker 1: did he pick MV squared? As the quantity that was

347
00:18:36,400 --> 00:18:39,119
Speaker 1: concerned was just something specific he was studying. He didn't

348
00:18:39,160 --> 00:18:41,400
Speaker 1: know why. He was just sort of like playing around.

349
00:18:41,560 --> 00:18:43,920
Speaker 1: You know, it's sort of like a discovery in mathematics,

350
00:18:44,000 --> 00:18:45,600
Speaker 1: But what do you mean it playing around around with

351
00:18:45,640 --> 00:18:47,879
Speaker 1: what you know? At that time, people didn't understand motion.

352
00:18:48,200 --> 00:18:51,280
Speaker 1: Newton hadn't developed his laws yet, so people would just

353
00:18:51,320 --> 00:18:53,920
Speaker 1: like multiplying random stuff together and seeing what it could do.

354
00:18:54,320 --> 00:18:56,800
Speaker 1: You know, there's not that many ways to combine basic

355
00:18:56,880 --> 00:19:00,160
Speaker 1: quantities mass and velocity in these things, and so it's

356
00:19:00,160 --> 00:19:02,080
Speaker 1: not that hard to study them. You know, across the

357
00:19:02,119 --> 00:19:06,159
Speaker 1: English channel, Newton was studying momentum, mass, time, velocity. So

358
00:19:06,280 --> 00:19:09,120
Speaker 1: likeness has just multiplied it by velocity one more time.

359
00:19:09,240 --> 00:19:12,280
Speaker 1: I'm sure he studied other quantities like mass squared times

360
00:19:12,280 --> 00:19:15,640
Speaker 1: of loss that didn't have any interesting properties. You make

361
00:19:15,640 --> 00:19:17,159
Speaker 1: it sound like a bunch of monkeys in a in

362
00:19:17,200 --> 00:19:19,840
Speaker 1: an infinite room piping that typewriter. It's a bunch of

363
00:19:19,840 --> 00:19:22,000
Speaker 1: grass students in an infinite room, and they all come

364
00:19:22,119 --> 00:19:24,080
Speaker 1: with one quantity and they're like, oh, this one's not interesting.

365
00:19:24,080 --> 00:19:26,200
Speaker 1: Oh look at this one. This one seems to be conserved.

366
00:19:26,240 --> 00:19:28,840
Speaker 1: I wonder what that means, but I guess, I mean, like,

367
00:19:28,960 --> 00:19:31,399
Speaker 1: what did he see it conserved in? Do you know

368
00:19:31,400 --> 00:19:33,720
Speaker 1: what I mean? Like he calculated in for one thing

369
00:19:33,760 --> 00:19:36,119
Speaker 1: and then for another, and then he saw that it

370
00:19:36,160 --> 00:19:38,840
Speaker 1: was the same. I guess, But what was that thing? Yes, So,

371
00:19:38,880 --> 00:19:41,399
Speaker 1: for example, physicists of this age like to do calculations

372
00:19:41,400 --> 00:19:44,560
Speaker 1: about billiard balls. Right now, billiards is a very very

373
00:19:44,560 --> 00:19:46,960
Speaker 1: old game. So you can take the kinetic energy of

374
00:19:47,000 --> 00:19:49,120
Speaker 1: the first ball and then it hits another one, maybe

375
00:19:49,160 --> 00:19:51,159
Speaker 1: it has a different mass, but you notice that the

376
00:19:51,240 --> 00:19:54,879
Speaker 1: kinetic energy is conserved, and so you can do simple

377
00:19:54,880 --> 00:19:57,679
Speaker 1: calculations there and see that kinetic energy is conserved in

378
00:19:57,720 --> 00:20:02,080
Speaker 1: these systems, so like after a collision. Then they noticed

379
00:20:02,119 --> 00:20:04,960
Speaker 1: that this quantity seems to stay the same, Like you

380
00:20:05,000 --> 00:20:07,399
Speaker 1: added up at the beginning for the two balls, and

381
00:20:07,440 --> 00:20:09,200
Speaker 1: then you added up at the end for the two balls,

382
00:20:09,240 --> 00:20:11,480
Speaker 1: and it seemed to be the same. Is that what happened,

383
00:20:11,480 --> 00:20:13,480
Speaker 1: because if you look at the velocities, the velocities don't

384
00:20:13,480 --> 00:20:15,440
Speaker 1: stay the same. That's right. The velocities do not stay

385
00:20:15,480 --> 00:20:17,800
Speaker 1: the same unless the two masses are the same. But

386
00:20:17,920 --> 00:20:20,959
Speaker 1: like the really slow moving massive ball bumps into a

387
00:20:21,080 --> 00:20:23,640
Speaker 1: very light ball, a low mass ball, that low mass

388
00:20:23,640 --> 00:20:26,240
Speaker 1: ball will fly off at higher speeds, and so you're write,

389
00:20:26,320 --> 00:20:29,480
Speaker 1: velocity isn't conserved. But this weird combination of mass and

390
00:20:29,600 --> 00:20:32,800
Speaker 1: velocity squared did seem to be conserved. So that was

391
00:20:32,800 --> 00:20:35,440
Speaker 1: sort of like an experimental discovery that lenn has made.

392
00:20:35,880 --> 00:20:38,520
Speaker 1: And you know, this idea of conservation means it might

393
00:20:38,560 --> 00:20:41,320
Speaker 1: be something important, It might be something like fundamental to

394
00:20:41,400 --> 00:20:44,199
Speaker 1: the universe. It's like, there's the philosophy aspect to it. Right,

395
00:20:44,480 --> 00:20:46,760
Speaker 1: just because something is conserved, why do we care? Because

396
00:20:46,760 --> 00:20:49,680
Speaker 1: it reveals something about the inner workings of the universe.

397
00:20:49,720 --> 00:20:52,680
Speaker 1: I think about this sometimes an analogy to other systems,

398
00:20:52,720 --> 00:20:55,639
Speaker 1: like economics, or like the water system. You know, like

399
00:20:55,880 --> 00:20:58,680
Speaker 1: water goes through lots of different forms. It rains into

400
00:20:58,720 --> 00:21:00,800
Speaker 1: the ocean and evaporates back up in the clouds, that

401
00:21:00,880 --> 00:21:03,199
Speaker 1: flows down rivers, but in the end, the water is

402
00:21:03,200 --> 00:21:06,640
Speaker 1: the water. It's changing, it's transforming, but it's flowing through

403
00:21:06,640 --> 00:21:08,760
Speaker 1: the system. The amount of water isn't changing. So that

404
00:21:08,800 --> 00:21:11,840
Speaker 1: tells you that, like water is deeply important to this

405
00:21:11,920 --> 00:21:14,320
Speaker 1: whole cycle. Right, if you identify a quantity which is

406
00:21:14,320 --> 00:21:17,000
Speaker 1: conserved in physical processes, you get the sense that maybe

407
00:21:17,080 --> 00:21:19,520
Speaker 1: it's important, right. I think what you're saying is that

408
00:21:19,600 --> 00:21:22,280
Speaker 1: sometimes we notice that there are things that sort of

409
00:21:22,320 --> 00:21:25,479
Speaker 1: don't disappear, like you're saying water. In the water cycle,

410
00:21:25,640 --> 00:21:28,840
Speaker 1: water it changes shape and it changes forms and it

411
00:21:28,960 --> 00:21:31,280
Speaker 1: changes states, but it's still sort of like you know,

412
00:21:31,320 --> 00:21:34,720
Speaker 1: the water, the molecules don't disappear. And maybe in the

413
00:21:34,720 --> 00:21:37,520
Speaker 1: case of the billiard balls that you notice that this quantity,

414
00:21:37,560 --> 00:21:39,720
Speaker 1: like if you computed, it's there in the beginning, and

415
00:21:39,760 --> 00:21:43,240
Speaker 1: it's there at the end, and somehow it got like transform.

416
00:21:43,280 --> 00:21:45,800
Speaker 1: So maybe it's like a thing itself. Yeah, because it's

417
00:21:45,800 --> 00:21:48,960
Speaker 1: easy to think of counter examples, like the number of bananas. Right,

418
00:21:49,280 --> 00:21:51,640
Speaker 1: the number of bananas is not constant in the universe.

419
00:21:51,920 --> 00:21:54,359
Speaker 1: You can make more bananas, you can eat bananas, right,

420
00:21:54,400 --> 00:21:57,159
Speaker 1: They can disappear, they can be destroyed, they can be created. Right.

421
00:21:57,200 --> 00:22:00,360
Speaker 1: The number of bananas is not fundamentally interesting to the verse,

422
00:22:00,560 --> 00:22:03,080
Speaker 1: even if it might be personally interesting to various people.

423
00:22:03,280 --> 00:22:06,720
Speaker 1: Well that you know, if right, Daniel, Like maybe they're

424
00:22:07,440 --> 00:22:10,000
Speaker 1: I you haven't starved the whole universe. Maybe every time

425
00:22:10,000 --> 00:22:13,159
Speaker 1: someone needs a banana here, bananas born in another planet

426
00:22:13,160 --> 00:22:15,480
Speaker 1: somewhere in the universe. Right, you don't know exactly. And

427
00:22:15,520 --> 00:22:17,840
Speaker 1: if you discovered that to be true, that would mean

428
00:22:18,000 --> 00:22:20,840
Speaker 1: something deep about bananas and the relationship to the universe.

429
00:22:20,840 --> 00:22:23,359
Speaker 1: That would be a huge discovery. That would be crazy,

430
00:22:23,400 --> 00:22:26,840
Speaker 1: wouldn't it, Like somehow the universe likes to keep the

431
00:22:26,840 --> 00:22:29,520
Speaker 1: same number of bananas all the time. That would be weird. Right,

432
00:22:29,560 --> 00:22:31,440
Speaker 1: And if you eat a banana here or destroy it

433
00:22:31,600 --> 00:22:34,320
Speaker 1: or make a bananas movie, another banana is born somewhere,

434
00:22:34,320 --> 00:22:36,320
Speaker 1: that would be really strange. That would be very strange,

435
00:22:36,320 --> 00:22:37,800
Speaker 1: and it would be a big clue. It would say

436
00:22:37,840 --> 00:22:41,080
Speaker 1: the universe is kind of banana or bananas are fundamental

437
00:22:41,119 --> 00:22:43,880
Speaker 1: to the universe. So when you discover a conserved quantity

438
00:22:43,960 --> 00:22:47,040
Speaker 1: something the universe maintains, then you're seeing something about the

439
00:22:47,040 --> 00:22:50,399
Speaker 1: inner workings of the universe. It's revealing to you what's important,

440
00:22:50,800 --> 00:22:53,000
Speaker 1: just like how water is important in the water cycle,

441
00:22:53,080 --> 00:22:56,040
Speaker 1: whereas clouds are not. So if kinetic energy is conserved,

442
00:22:56,080 --> 00:22:58,840
Speaker 1: liveness thought, well, this must be an important thing, you know.

443
00:22:59,000 --> 00:23:00,879
Speaker 1: I think if you tell anyone these days, like hey,

444
00:23:00,960 --> 00:23:03,840
Speaker 1: energy is conserved or waters conserved, nobody would blink and

445
00:23:03,880 --> 00:23:06,119
Speaker 1: I but if you tell them, like, hey, did you

446
00:23:06,160 --> 00:23:08,960
Speaker 1: know the universe conserves bananas, that would be a big

447
00:23:09,040 --> 00:23:11,840
Speaker 1: revelation about the universe, just like how we should look

448
00:23:11,840 --> 00:23:15,359
Speaker 1: at energy and water as being kind of a big deal. Right. Yeah,

449
00:23:15,400 --> 00:23:17,639
Speaker 1: And just in case anybody is being misled, as far

450
00:23:17,680 --> 00:23:20,239
Speaker 1: as we know, the universe does not conserve bananas, as

451
00:23:20,280 --> 00:23:21,679
Speaker 1: far as we know. Yes, as far as we know.

452
00:23:21,760 --> 00:23:24,720
Speaker 1: For example, I'm pretty sure there were billions of years

453
00:23:24,720 --> 00:23:27,200
Speaker 1: in which they were exactly zero bananas in the universe

454
00:23:27,320 --> 00:23:29,520
Speaker 1: that you know of that I know of, Yes, But

455
00:23:29,720 --> 00:23:32,280
Speaker 1: maybe all the bananas that are appearing on Earth mean

456
00:23:32,320 --> 00:23:35,320
Speaker 1: that they're anti bananas being created on alien world somewhere

457
00:23:35,320 --> 00:23:38,520
Speaker 1: else to balance that. Or I think you're saying what

458
00:23:38,720 --> 00:23:40,840
Speaker 1: happened before the Earth with four maybe there were other

459
00:23:40,840 --> 00:23:44,280
Speaker 1: planets with bananas. I'm just saying, keep an open mind.

460
00:23:44,400 --> 00:23:47,760
Speaker 1: You're saying bananas could predate the Earth. Yeah, that's my

461
00:23:47,840 --> 00:23:53,840
Speaker 1: theory of bananas. Well, I think your philosophy is bananas. Yeah.

462
00:23:53,960 --> 00:23:56,720
Speaker 1: But anyways, I think obviously trying to make the point

463
00:23:56,760 --> 00:23:59,080
Speaker 1: that you know, we should be sort of amaze and

464
00:23:59,280 --> 00:24:02,240
Speaker 1: awed at the act that energy seems to be conserved

465
00:24:02,240 --> 00:24:04,840
Speaker 1: in that water and for example, that water cycle is

466
00:24:04,880 --> 00:24:07,680
Speaker 1: conserved because it doesn't have to write. I think that's

467
00:24:07,720 --> 00:24:09,480
Speaker 1: what you're saying to You can come up with all

468
00:24:09,560 --> 00:24:11,639
Speaker 1: sorts of quantities, you can define them, and most of

469
00:24:11,640 --> 00:24:13,879
Speaker 1: them are not conserved. So when you find one that

470
00:24:14,080 --> 00:24:16,560
Speaker 1: is that tells you you're onto something, it's a really

471
00:24:16,600 --> 00:24:19,760
Speaker 1: interesting clue. All right, So then I guess that leapness

472
00:24:19,880 --> 00:24:22,440
Speaker 1: called this energy. Did he coined the phrase or was

473
00:24:22,480 --> 00:24:24,520
Speaker 1: he the first one to use it? On envy square.

474
00:24:24,560 --> 00:24:27,600
Speaker 1: Did he call it kinetic energy? Also know, he called

475
00:24:27,600 --> 00:24:29,679
Speaker 1: it vis visa, which is I think Latin for like

476
00:24:29,760 --> 00:24:31,840
Speaker 1: a living force. And you know, now we know the

477
00:24:31,920 --> 00:24:35,120
Speaker 1: kinetic energy on its own isn't actually conserved. I mean,

478
00:24:35,200 --> 00:24:39,360
Speaker 1: under certain assumptions it is. In elastic collisions, we don't

479
00:24:39,359 --> 00:24:42,920
Speaker 1: break things up, kinetic energy is conserved, but on its own,

480
00:24:43,000 --> 00:24:46,400
Speaker 1: kinetic energy more generally isn't conservative. Course, And I think

481
00:24:46,400 --> 00:24:49,240
Speaker 1: Newton was mostly looking at momentum, right, because that one

482
00:24:49,320 --> 00:24:53,000
Speaker 1: is conserved in most collisions. Yeah, momentum is actually conserved.

483
00:24:53,000 --> 00:24:56,760
Speaker 1: So Newton's combination of kinematic variables mass times velocity, momentum,

484
00:24:56,920 --> 00:24:59,440
Speaker 1: this thing actually is conserved. But again, at the time,

485
00:24:59,600 --> 00:25:01,920
Speaker 1: nobody knew why. It wasn't until we had a great

486
00:25:01,960 --> 00:25:04,760
Speaker 1: mathematical genius a couple hundred years later who told us

487
00:25:04,960 --> 00:25:08,600
Speaker 1: about the connections between conservation laws and symmetries, how these

488
00:25:08,760 --> 00:25:12,080
Speaker 1: conservation laws revealed deep symmetries of the universe. Well, I

489
00:25:12,080 --> 00:25:14,399
Speaker 1: mean that's what they thought, was that the fundamental law

490
00:25:14,400 --> 00:25:16,720
Speaker 1: of the universe, right, the momentum is conserved. Yeah, the

491
00:25:16,760 --> 00:25:20,440
Speaker 1: momentum conservation was discovered before we understood what it meant

492
00:25:20,600 --> 00:25:23,960
Speaker 1: and why we have it. What symmetry of the universe created.

493
00:25:24,200 --> 00:25:26,600
Speaker 1: We just did a whole podcast episode about why momentum

494
00:25:26,640 --> 00:25:29,399
Speaker 1: is conserved. It's really fun and deep topic. Okay, so

495
00:25:29,440 --> 00:25:31,320
Speaker 1: that's one kind of energy. What were some of the

496
00:25:31,320 --> 00:25:33,399
Speaker 1: other kinds of energy we've discovered? So there is a

497
00:25:33,480 --> 00:25:36,760
Speaker 1: second kind of energy, potential energy, which is a different

498
00:25:36,840 --> 00:25:39,560
Speaker 1: kind of energy from kinetic energy and something I've never

499
00:25:39,600 --> 00:25:43,600
Speaker 1: really been comfortable with. Wait, what potential energy makes you uncomfortable?

500
00:25:43,960 --> 00:25:46,359
Speaker 1: You don't like the idea of potential I don't want

501
00:25:46,400 --> 00:25:50,000
Speaker 1: any surprises. Just give me straight up energy. Yeah, potential

502
00:25:50,119 --> 00:25:52,840
Speaker 1: energy is weird and confusing. It's definitely a different kind

503
00:25:52,880 --> 00:25:55,880
Speaker 1: of energy than kinetic energy, but it's also closely related

504
00:25:55,920 --> 00:26:00,000
Speaker 1: to kinetic energy because while kinetic energy by itself isn't conserved,

505
00:26:00,560 --> 00:26:07,280
Speaker 1: some kinetic plus potential that is conserved in the universe. Mm. Interesting. Well, okay,

506
00:26:07,320 --> 00:26:10,000
Speaker 1: let's get into the details of that, and I want

507
00:26:10,040 --> 00:26:12,680
Speaker 1: to know why it makes you uncomfortable. But first, let's

508
00:26:12,680 --> 00:26:27,719
Speaker 1: take a quick break. Wright. We're talking about energy, and

509
00:26:27,760 --> 00:26:31,080
Speaker 1: it's been a very energetic discussion here. Daniel talked about

510
00:26:31,160 --> 00:26:33,280
Speaker 1: how you know humans when we start to try to

511
00:26:33,480 --> 00:26:35,520
Speaker 1: understand the world, we came up with the idea of

512
00:26:35,680 --> 00:26:39,400
Speaker 1: energy because it seems to be conserved in some circumstances,

513
00:26:39,560 --> 00:26:42,800
Speaker 1: and that was kinetic energy. But there's also potential energy,

514
00:26:43,000 --> 00:26:45,280
Speaker 1: which is kind of a weird concept in physics, right,

515
00:26:45,320 --> 00:26:47,479
Speaker 1: it makes you uncomfortable. Yeah, it is a weird concept

516
00:26:47,480 --> 00:26:49,960
Speaker 1: in physics, but it's also something sort of intuitive. Like

517
00:26:50,160 --> 00:26:52,159
Speaker 1: let's say you have a banana on the top of

518
00:26:52,200 --> 00:26:54,960
Speaker 1: a bookshelf and it's just sitting there right not doing anything,

519
00:26:55,040 --> 00:26:56,760
Speaker 1: and you bump it and it falls off before it

520
00:26:56,840 --> 00:26:59,440
Speaker 1: hits the ground. It's going pretty fast, so it has

521
00:26:59,520 --> 00:27:03,320
Speaker 1: kinetic energy. Where did that kinetic energy come from? Right?

522
00:27:03,400 --> 00:27:06,160
Speaker 1: It came from its height. It came from the fact

523
00:27:06,160 --> 00:27:09,320
Speaker 1: that it was sitting high up above the ground, and

524
00:27:09,359 --> 00:27:13,440
Speaker 1: it turned that height in the gravitational field into energy.

525
00:27:13,520 --> 00:27:16,639
Speaker 1: So that's the potential energy of the banana getting turned

526
00:27:16,680 --> 00:27:19,600
Speaker 1: into kinetic energy of the banana. So it's definitely energy

527
00:27:19,640 --> 00:27:22,840
Speaker 1: because you can transform it into kinetic energy into motion.

528
00:27:23,320 --> 00:27:26,719
Speaker 1: But it's sort of weird because it's energy of its location.

529
00:27:26,760 --> 00:27:29,679
Speaker 1: It's energy of its configuration, right right. I think that's

530
00:27:29,720 --> 00:27:32,040
Speaker 1: where the name potential comes from. Like, it doesn't really

531
00:27:32,080 --> 00:27:34,280
Speaker 1: have energy right now, it's just sitting on the table.

532
00:27:34,760 --> 00:27:37,400
Speaker 1: It doesn't really it's not really moving, but it has

533
00:27:37,400 --> 00:27:41,240
Speaker 1: a potential to move along. Yeah. I think that's tempting

534
00:27:41,240 --> 00:27:43,359
Speaker 1: to describe it that way, but it really is energy.

535
00:27:43,440 --> 00:27:46,840
Speaker 1: Potential energy is not just like the potential to have energy.

536
00:27:47,000 --> 00:27:50,560
Speaker 1: It comes from energy of a potential. Potential is the

537
00:27:50,560 --> 00:27:53,639
Speaker 1: way we describe how a field impacts a force on

538
00:27:53,680 --> 00:27:57,200
Speaker 1: an object, Like an electron moving through a potential you know,

539
00:27:57,320 --> 00:28:00,000
Speaker 1: feels a force, right. But I think you're getting mixed up,

540
00:28:00,280 --> 00:28:02,480
Speaker 1: you know, kind of tripped up here because you're saying

541
00:28:02,640 --> 00:28:05,920
Speaker 1: it's in a potential because it has the potential to move,

542
00:28:06,640 --> 00:28:07,720
Speaker 1: to cause it to move, you know what I I mean.

543
00:28:07,760 --> 00:28:10,320
Speaker 1: It's like a circular definition. Yeah, it has the potential

544
00:28:10,359 --> 00:28:12,480
Speaker 1: to move exactly. So we don't really know what this

545
00:28:12,520 --> 00:28:15,439
Speaker 1: stuff is. Potential energy. I always found it really strange.

546
00:28:15,560 --> 00:28:18,320
Speaker 1: Mostly it makes me uncomfortable because it doesn't really have

547
00:28:18,600 --> 00:28:22,520
Speaker 1: a value in itself. It's relational like the banana. How

548
00:28:22,600 --> 00:28:25,560
Speaker 1: much potential energy does it have at the top of

549
00:28:25,560 --> 00:28:28,000
Speaker 1: the bookshelf. We don't know. There's no number, but it

550
00:28:28,040 --> 00:28:31,440
Speaker 1: has more potential energy than at the bottom of the bookshelf.

551
00:28:31,880 --> 00:28:34,879
Speaker 1: Potential energy is only important in differences, and you can

552
00:28:34,920 --> 00:28:37,399
Speaker 1: add an arbitrary number to the potential energy of the

553
00:28:37,400 --> 00:28:40,320
Speaker 1: banana at the bookshelf. Doesn't matter. The only thing that

554
00:28:40,320 --> 00:28:42,520
Speaker 1: matters is how much more potential energy it has the

555
00:28:42,560 --> 00:28:45,400
Speaker 1: top in the bottom right. Like it's a relative quantity

556
00:28:45,520 --> 00:28:47,160
Speaker 1: kind of like it depends on where you measure, and

557
00:28:47,160 --> 00:28:48,880
Speaker 1: if you measure it from the floor, it's one thing.

558
00:28:48,920 --> 00:28:51,320
Speaker 1: If you measure it from the table, it's zero. Yeah.

559
00:28:51,360 --> 00:28:53,760
Speaker 1: It's sort of like velocity in that sense. It's no

560
00:28:53,840 --> 00:28:56,120
Speaker 1: meaning to say you're moving at a certain speed. You're

561
00:28:56,120 --> 00:28:58,680
Speaker 1: only moving at a certain speed relative to something else.

562
00:28:59,120 --> 00:29:02,560
Speaker 1: The banana has pential energy relative to the floor. And

563
00:29:02,600 --> 00:29:04,960
Speaker 1: something that's fascinating is that it's very easy to see

564
00:29:05,040 --> 00:29:08,280
Speaker 1: kinetic energy and potential energy slashing back and forth into

565
00:29:08,360 --> 00:29:10,640
Speaker 1: each other. If you have, for example, a ball, and

566
00:29:10,760 --> 00:29:13,840
Speaker 1: you drop it, then it's potential energy is getting turned

567
00:29:13,840 --> 00:29:16,200
Speaker 1: into kinetic energy, and then it gets turned around when

568
00:29:16,200 --> 00:29:18,360
Speaker 1: it hits the floor, and it's kinetic energy then gets

569
00:29:18,400 --> 00:29:21,160
Speaker 1: turned back into potential energy as it climbs back up

570
00:29:21,200 --> 00:29:24,320
Speaker 1: to your hand. And if there wasn't friction or air resistance,

571
00:29:24,440 --> 00:29:27,320
Speaker 1: then it would just go on forever, smoothly sliding back

572
00:29:27,360 --> 00:29:29,959
Speaker 1: between the two different forms of energy, right, Like, if

573
00:29:29,960 --> 00:29:32,880
Speaker 1: it was jumping on an infinite trampoline kind of like

574
00:29:32,920 --> 00:29:36,360
Speaker 1: a perfect trampoline, this energy would, like the kinetic energy

575
00:29:36,360 --> 00:29:38,720
Speaker 1: would appear and disappear, appear and disappear, and the pinetial

576
00:29:38,800 --> 00:29:41,600
Speaker 1: energy would also appear and disappear, but it would always

577
00:29:41,600 --> 00:29:43,400
Speaker 1: add up to the same thing. It would always added

578
00:29:43,400 --> 00:29:45,080
Speaker 1: to the same thing. And a trampoline is a great

579
00:29:45,120 --> 00:29:48,880
Speaker 1: example because it's basically like a spring. Springs have potential

580
00:29:48,960 --> 00:29:52,040
Speaker 1: energy in them also, right, You squeeze a spring that

581
00:29:52,120 --> 00:29:54,840
Speaker 1: takes energy, and now the energy you put into squeezing

582
00:29:54,840 --> 00:29:57,720
Speaker 1: it is somehow stored in the spring, in the arrangement

583
00:29:57,760 --> 00:30:00,800
Speaker 1: of the spring, the compactification of the as bonds that

584
00:30:00,800 --> 00:30:03,320
Speaker 1: would prefer to be relaxed, And so that's the same

585
00:30:03,440 --> 00:30:05,760
Speaker 1: kind of energy. You can put it into a gravitational field,

586
00:30:06,000 --> 00:30:08,160
Speaker 1: you can put it into a spring, you can put

587
00:30:08,200 --> 00:30:10,360
Speaker 1: it into a squeezing of a ball, which is basically

588
00:30:10,400 --> 00:30:14,680
Speaker 1: another spring. And so all these things are potential energy, right,

589
00:30:14,720 --> 00:30:16,560
Speaker 1: And in that sense, you can sort of think of

590
00:30:16,600 --> 00:30:18,880
Speaker 1: it as a thing. Right, it's just the thing that

591
00:30:18,960 --> 00:30:23,320
Speaker 1: changes from being kinetic to being potential, Like it's somehow

592
00:30:23,400 --> 00:30:26,600
Speaker 1: there and it's always conserved. But is it a thing?

593
00:30:26,640 --> 00:30:29,440
Speaker 1: When you say a thing, I think something physical, you know,

594
00:30:29,520 --> 00:30:31,960
Speaker 1: like water is flowing. And for a long time people

595
00:30:31,960 --> 00:30:34,280
Speaker 1: who are wondering, like is energy a thing to like

596
00:30:34,480 --> 00:30:36,840
Speaker 1: flow from one thing to another? Is it made of

597
00:30:36,840 --> 00:30:40,400
Speaker 1: little energy particles? But here because potential energy is a

598
00:30:40,440 --> 00:30:43,360
Speaker 1: kind of energy, and it's just an arrangement of other things.

599
00:30:43,480 --> 00:30:45,880
Speaker 1: And is it itself a thing or is it just

600
00:30:45,920 --> 00:30:49,200
Speaker 1: the arrangement of other things. It's complicated, you mean, like

601
00:30:49,240 --> 00:30:51,920
Speaker 1: does it have a physical embodiment or is it just

602
00:30:52,080 --> 00:30:55,680
Speaker 1: I don't know, like a label we put on other things. Yeah,

603
00:30:55,720 --> 00:30:57,520
Speaker 1: that's a deep question. I'm not sure the answer to

604
00:30:58,080 --> 00:31:00,360
Speaker 1: the same question can be asked, like you know makes

605
00:31:00,400 --> 00:31:02,960
Speaker 1: you you? You were made of the same particles as

606
00:31:03,040 --> 00:31:05,680
Speaker 1: I am, you just arranged a different way. So the

607
00:31:05,760 --> 00:31:09,040
Speaker 1: units is in the arrangement of the particles, the same way.

608
00:31:09,080 --> 00:31:13,320
Speaker 1: Potential energy comes from configuration of particles together, not the

609
00:31:13,360 --> 00:31:17,000
Speaker 1: particles themselves. The potential energy isn't stored in the particle,

610
00:31:17,080 --> 00:31:20,400
Speaker 1: It's in the relationship between the particles, right right, unless

611
00:31:20,440 --> 00:31:23,840
Speaker 1: you're a zombie, in which case your body is arrangement.

612
00:31:23,920 --> 00:31:27,960
Speaker 1: Is the decay? Well, I guess, but what about mass?

613
00:31:28,000 --> 00:31:30,720
Speaker 1: You know, like, we know that mass is the same

614
00:31:30,760 --> 00:31:32,680
Speaker 1: as energy kind of in a way, right, according to

615
00:31:32,720 --> 00:31:36,080
Speaker 1: equals empty squared is mass energy. Then I'm going to

616
00:31:36,160 --> 00:31:39,840
Speaker 1: take probably surprising and weird philosophical position here, which is

617
00:31:40,200 --> 00:31:43,520
Speaker 1: that mass is not its own kind of energy. Mass

618
00:31:43,720 --> 00:31:46,720
Speaker 1: is just a representation of how much energy is stored

619
00:31:46,800 --> 00:31:51,360
Speaker 1: inside something, how much kinetic and potential energy is in something.

620
00:31:51,520 --> 00:31:54,000
Speaker 1: What do you mean like things don't have inherent mass,

621
00:31:54,000 --> 00:31:56,520
Speaker 1: Like don't particle from the fundamental particles, don't they have

622
00:31:56,880 --> 00:31:59,400
Speaker 1: you know, mass, Like the electron has mass? Right, yeah,

623
00:31:59,440 --> 00:32:02,440
Speaker 1: so let's break it down, Like the electron fundamentally doesn't

624
00:32:02,520 --> 00:32:05,120
Speaker 1: have mass on its own. Its mass comes from its

625
00:32:05,120 --> 00:32:08,560
Speaker 1: interactions with the Higgs field. So that's the kinetic and

626
00:32:08,560 --> 00:32:11,920
Speaker 1: potential energy of the Higgs field, which changes how the

627
00:32:11,960 --> 00:32:15,160
Speaker 1: electron moves through the universe as if it did have mass.

628
00:32:15,200 --> 00:32:16,840
Speaker 1: But if you listen to our episode on like what

629
00:32:17,040 --> 00:32:20,240
Speaker 1: is renormalization, what is the electron's true mass and charge?

630
00:32:20,680 --> 00:32:24,000
Speaker 1: Discover that fundamentally, truly, the electron and the other particles

631
00:32:24,280 --> 00:32:27,920
Speaker 1: have no mass on their own, It's all in their energy, right,

632
00:32:27,960 --> 00:32:30,680
Speaker 1: Because I guess even the electron it's it's not like

633
00:32:30,680 --> 00:32:32,080
Speaker 1: that has a little bit of stuff in the middle.

634
00:32:32,120 --> 00:32:34,560
Speaker 1: It just has the potential to interact with the Higgs field.

635
00:32:34,600 --> 00:32:36,600
Speaker 1: And that's what we call its mass. That's what we

636
00:32:36,640 --> 00:32:39,160
Speaker 1: call its mass. I act to truck because we're doing

637
00:32:39,160 --> 00:32:42,120
Speaker 1: this podcast, but really because we wrote a chapter on

638
00:32:42,160 --> 00:32:45,280
Speaker 1: it for our second book. Frequently asked questions about the universe. Yeah,

639
00:32:45,320 --> 00:32:47,760
Speaker 1: and if you think about composite particles like a proton,

640
00:32:47,840 --> 00:32:50,440
Speaker 1: and proton is made out of quarks, those corks have

641
00:32:50,480 --> 00:32:52,840
Speaker 1: almost no mass, but the proton has a good bit

642
00:32:52,880 --> 00:32:55,200
Speaker 1: of mass. Where does that come from? It comes from

643
00:32:55,200 --> 00:32:59,280
Speaker 1: the energy that binds those corks together. So the protons

644
00:32:59,320 --> 00:33:03,280
Speaker 1: mass some other weird kind of mass in the universe,

645
00:33:03,320 --> 00:33:06,600
Speaker 1: not like you're converting kinetic energy into some sort of substance.

646
00:33:06,920 --> 00:33:10,280
Speaker 1: It just comes from its internal stored energy. So the

647
00:33:10,320 --> 00:33:12,160
Speaker 1: way I think about mass is sort of like an

648
00:33:12,200 --> 00:33:16,440
Speaker 1: indicator tells you how much energy is internally stored inside

649
00:33:16,440 --> 00:33:19,200
Speaker 1: this thing. In the end, it's all just energy. Mass

650
00:33:19,280 --> 00:33:22,240
Speaker 1: isn't its own form of energy. It just reflects how

651
00:33:22,320 --> 00:33:25,720
Speaker 1: much energy is inside something. You're basically saying, all masses

652
00:33:25,720 --> 00:33:29,480
Speaker 1: just potential energy, potential and kinetic energy. Right, some of

653
00:33:29,520 --> 00:33:32,360
Speaker 1: the protons. Mass comes from the kinetic energy of those

654
00:33:32,360 --> 00:33:36,040
Speaker 1: gluons and quarks slashing around, So not just potential energy

655
00:33:36,080 --> 00:33:39,120
Speaker 1: but also kinetic all right. So I think what you're

656
00:33:39,120 --> 00:33:42,880
Speaker 1: saying is that we're trying to define energy. One way

657
00:33:42,880 --> 00:33:44,600
Speaker 1: to do it is to look at its different kinds,

658
00:33:45,200 --> 00:33:47,200
Speaker 1: and there are really toward fens that there's only two

659
00:33:47,280 --> 00:33:50,840
Speaker 1: kinds of energy, kinetic energy and potential energy. There are

660
00:33:50,840 --> 00:33:53,080
Speaker 1: no other other kinds, right, are there? I mean there's

661
00:33:53,160 --> 00:33:57,320
Speaker 1: dark energy. Wow, way to secure us with our own

662
00:33:57,400 --> 00:34:01,000
Speaker 1: terrible names. You totally right, But we don't know what

663
00:34:01,080 --> 00:34:04,080
Speaker 1: dark energy is. One theory is that it's like the

664
00:34:04,120 --> 00:34:08,040
Speaker 1: fundamental quantum potential energy of all of these fields, in

665
00:34:08,080 --> 00:34:10,280
Speaker 1: which case it would be a kind of potential energy.

666
00:34:10,600 --> 00:34:12,680
Speaker 1: But we really just don't know what dark energy is.

667
00:34:12,680 --> 00:34:16,680
Speaker 1: It's a big mystery, all right. So ignore the scent

668
00:34:16,719 --> 00:34:19,799
Speaker 1: of the universe that is dark energy for this discussion

669
00:34:20,239 --> 00:34:23,680
Speaker 1: and let's just focus on the small bit of it

670
00:34:23,760 --> 00:34:26,200
Speaker 1: that we like to talk about. No, it's a great point,

671
00:34:26,200 --> 00:34:29,000
Speaker 1: but when we do figure out what dark energy is,

672
00:34:29,600 --> 00:34:32,520
Speaker 1: either it will be kinetic energy or to be potential energy,

673
00:34:32,840 --> 00:34:35,160
Speaker 1: or it'll be some new kind of bonkers energy. And

674
00:34:35,200 --> 00:34:37,200
Speaker 1: I'll be wrong, in which case I'll be the first

675
00:34:37,200 --> 00:34:40,799
Speaker 1: to celebrate. Well, yeah, basically, like I said, let's just

676
00:34:40,880 --> 00:34:45,839
Speaker 1: ignore of the universe that is dark energy. And uh,

677
00:34:46,000 --> 00:34:48,799
Speaker 1: you know, for our for what impacts is there's really

678
00:34:48,840 --> 00:34:52,319
Speaker 1: only two kinds of energy. You're saying, kinetic energy and

679
00:34:52,400 --> 00:34:55,840
Speaker 1: potential energy. And that's it, right, And that's kind of

680
00:34:55,840 --> 00:34:59,040
Speaker 1: what goes into your basic equations of the universe, right, Like,

681
00:34:59,120 --> 00:35:02,040
Speaker 1: that's basically the definition of the equations of the universe.

682
00:35:02,160 --> 00:35:05,360
Speaker 1: That's right. The Shortinger equation has kinetic energy plus potential

683
00:35:05,440 --> 00:35:08,880
Speaker 1: energy in it. Hamiltonian mechanics is built on that principle,

684
00:35:09,040 --> 00:35:11,960
Speaker 1: you know, Classical mechanics is based on the principle of

685
00:35:12,040 --> 00:35:14,319
Speaker 1: least action, and action in the end is defined in

686
00:35:14,480 --> 00:35:18,000
Speaker 1: terms of these two quantities, kinetic and potential energy. And

687
00:35:18,040 --> 00:35:21,440
Speaker 1: the deep mystery really is if these two things independently

688
00:35:21,520 --> 00:35:24,719
Speaker 1: are not conserved potential and kinetic energy, but together they are,

689
00:35:24,920 --> 00:35:27,360
Speaker 1: what does that mean about what they have in common?

690
00:35:27,800 --> 00:35:30,319
Speaker 1: And what is that commonality? I think that in the

691
00:35:30,440 --> 00:35:32,799
Speaker 1: end is the question what is energies? What do these

692
00:35:32,800 --> 00:35:36,560
Speaker 1: two things together, what larger picture do they make up? Right?

693
00:35:36,600 --> 00:35:38,480
Speaker 1: Because I think maybe that's something that maybe a lot

694
00:35:38,520 --> 00:35:41,000
Speaker 1: of people don't know. Is that when you know, in physics,

695
00:35:41,080 --> 00:35:43,320
Speaker 1: say oh, the laws of the universe or the equations

696
00:35:43,360 --> 00:35:46,960
Speaker 1: that define the universe, Really what you're talking about is

697
00:35:47,360 --> 00:35:51,440
Speaker 1: basically the idea that kinetic energy and potential energy is conserved,

698
00:35:51,520 --> 00:35:54,480
Speaker 1: because that's what you assume when you formulate the laws

699
00:35:54,480 --> 00:35:57,719
Speaker 1: of physics. Right, you start with, hey, let's assume that

700
00:35:57,800 --> 00:36:01,200
Speaker 1: kinetic and potential energy is conserved, you know, and then

701
00:36:01,360 --> 00:36:03,600
Speaker 1: let's see what kind of rules that gives us. I

702
00:36:03,640 --> 00:36:06,560
Speaker 1: think it actually goes the opposite direction. You can make

703
00:36:06,640 --> 00:36:10,280
Speaker 1: up laws to a universe that don't have conservation of energy.

704
00:36:10,360 --> 00:36:13,440
Speaker 1: If those laws, for example, are changing in time, then

705
00:36:13,480 --> 00:36:16,840
Speaker 1: they don't conserve energy. And one of the greatest insights

706
00:36:16,880 --> 00:36:20,439
Speaker 1: into this relationship between conservation laws and symmetries came when

707
00:36:20,440 --> 00:36:23,360
Speaker 1: people were asking about general relativity. They're like, hold on

708
00:36:23,400 --> 00:36:26,759
Speaker 1: a second, does general relativity conserve energy? That seems like

709
00:36:26,800 --> 00:36:29,120
Speaker 1: it should be important. So we actually derived the laws

710
00:36:29,120 --> 00:36:31,320
Speaker 1: from other places and then ask like, hold on a second,

711
00:36:31,560 --> 00:36:34,480
Speaker 1: is energy conserved? What does that mean about these things?

712
00:36:34,840 --> 00:36:36,719
Speaker 1: I guess I mean, like, you know, like the Hamiltonian

713
00:36:36,800 --> 00:36:39,279
Speaker 1: that's that's basically you're you saying Hey, the sum of

714
00:36:39,320 --> 00:36:42,279
Speaker 1: kinetic and potential energy should always stay the same, and

715
00:36:42,320 --> 00:36:45,279
Speaker 1: then from that you derive some of these other equations. Right, Well,

716
00:36:45,320 --> 00:36:48,520
Speaker 1: there's very non satisfactory physics definition. The answer to that,

717
00:36:48,920 --> 00:36:52,959
Speaker 1: which is that once you define the Hamiltonian, then energy

718
00:36:53,040 --> 00:36:56,080
Speaker 1: is defined to be the thing that's conserved if these

719
00:36:56,160 --> 00:36:58,600
Speaker 1: rules don't change in time. So you sort of start

720
00:36:58,680 --> 00:37:00,960
Speaker 1: from the Hamiltonian and and you figure out what is

721
00:37:01,000 --> 00:37:03,360
Speaker 1: the energy of the system from that, I guess what

722
00:37:03,400 --> 00:37:06,040
Speaker 1: I'm saying is um that it's It's a very fundamental

723
00:37:06,080 --> 00:37:09,239
Speaker 1: concept in in how theoretical physics works. Right. It's not

724
00:37:09,280 --> 00:37:11,600
Speaker 1: like you assume, like, hey, let's assume it's changing. What

725
00:37:11,680 --> 00:37:13,960
Speaker 1: does that give us? It's like you'd assume that it's

726
00:37:13,960 --> 00:37:16,040
Speaker 1: not changing. Kind of. I think there are different ways

727
00:37:16,080 --> 00:37:17,920
Speaker 1: to formulate the theories of the universe. And you can

728
00:37:17,960 --> 00:37:20,480
Speaker 1: either start from the assumption that energy is conserved to

729
00:37:20,560 --> 00:37:22,960
Speaker 1: figure out what rules are allowed, or you can just

730
00:37:23,000 --> 00:37:25,879
Speaker 1: start building laws and figuring out what the consequences are,

731
00:37:25,960 --> 00:37:29,640
Speaker 1: which ones actually describe our universe, and then noticing that

732
00:37:29,680 --> 00:37:32,040
Speaker 1: in the ones that describe our universe, this quantity we

733
00:37:32,120 --> 00:37:34,879
Speaker 1: call energy seems to be conserved. There's some different orders

734
00:37:34,880 --> 00:37:36,640
Speaker 1: you could use there. All right, well, I guess for

735
00:37:36,680 --> 00:37:39,960
Speaker 1: our discussion, the basic idea is that, you know, physicists

736
00:37:40,000 --> 00:37:42,920
Speaker 1: sort of describe or define energy as the sum of

737
00:37:43,000 --> 00:37:46,600
Speaker 1: kinetic energy plus potential energy. But what you're saying is

738
00:37:46,680 --> 00:37:49,279
Speaker 1: that that's kind of a weird thing to do, because, like,

739
00:37:49,719 --> 00:37:52,239
Speaker 1: how do you know kinetic energy and potation energy have

740
00:37:52,400 --> 00:37:54,640
Speaker 1: to be related to each other exactly? They seem like

741
00:37:54,760 --> 00:37:57,000
Speaker 1: very different things, right, What does it mean that these

742
00:37:57,040 --> 00:38:00,120
Speaker 1: two very different things are closely related? Like if you discovered, well,

743
00:38:00,160 --> 00:38:02,360
Speaker 1: the number of bananas in the universe isn't conserved, but

744
00:38:02,440 --> 00:38:05,960
Speaker 1: bananas plus apples that's conserved. That would be really interesting

745
00:38:06,000 --> 00:38:08,640
Speaker 1: connection between bananas and apples. You're like, it turns out

746
00:38:08,640 --> 00:38:10,600
Speaker 1: to have more in common than I thought. Right, then

747
00:38:10,600 --> 00:38:13,840
Speaker 1: they have a kids song together, apples and bananas. I

748
00:38:13,840 --> 00:38:15,440
Speaker 1: think we need to hear a snippet of it. Go ahead,

749
00:38:15,880 --> 00:38:17,520
Speaker 1: all right, can you play it for us? Um, I

750
00:38:17,520 --> 00:38:20,080
Speaker 1: don't have my kazoo here otherwise I would. Well, I

751
00:38:20,160 --> 00:38:21,920
Speaker 1: think I think what you're saying is that it's kind

752
00:38:21,920 --> 00:38:23,480
Speaker 1: of weird to put them together. But if you put

753
00:38:23,480 --> 00:38:26,520
Speaker 1: it together, then it seems to be constant in the universe.

754
00:38:26,680 --> 00:38:29,919
Speaker 1: And it seems to give us these equations that seem

755
00:38:30,000 --> 00:38:32,600
Speaker 1: to work and seems to like predict where particles are

756
00:38:32,600 --> 00:38:34,359
Speaker 1: going to go and what's going to happen to them,

757
00:38:34,400 --> 00:38:37,000
Speaker 1: and what kinds there are even exactly. And what that

758
00:38:37,040 --> 00:38:39,760
Speaker 1: means is that they really do have something in common.

759
00:38:39,800 --> 00:38:42,759
Speaker 1: They're part of the same thing. They're not the same thing.

760
00:38:43,040 --> 00:38:46,080
Speaker 1: They're like two halves of a puzzle that clicked together

761
00:38:46,160 --> 00:38:48,759
Speaker 1: perfectly to make something new. And then we have to

762
00:38:48,760 --> 00:38:50,560
Speaker 1: ask the question, what does that mean where they have

763
00:38:50,560 --> 00:38:53,239
Speaker 1: in common? What is this larger thing that they're a

764
00:38:53,280 --> 00:38:56,399
Speaker 1: part of? All right? So then are they conserved? Because

765
00:38:56,400 --> 00:38:59,200
Speaker 1: I know sometimes they're not conserved. So they are conserved

766
00:38:59,400 --> 00:39:01,960
Speaker 1: in the case where the laws of physics do not change.

767
00:39:02,320 --> 00:39:04,200
Speaker 1: So the laws of physics you're using are the same

768
00:39:04,280 --> 00:39:06,359
Speaker 1: now and the same in ten minutes and the same

769
00:39:06,360 --> 00:39:10,040
Speaker 1: in a thousand years, then kinetic energy plus potential energy

770
00:39:10,239 --> 00:39:14,040
Speaker 1: is conserved. That's absolutely true. Now in our universe, the

771
00:39:14,120 --> 00:39:17,600
Speaker 1: laws of physics are almost the same from moment to moment.

772
00:39:18,080 --> 00:39:20,239
Speaker 1: They're usually the same. You can do the experiment the

773
00:39:20,320 --> 00:39:23,160
Speaker 1: Large Hadron Collider today and tomorrow and next year and

774
00:39:23,160 --> 00:39:25,279
Speaker 1: get the same measurements. But there is one way in

775
00:39:25,280 --> 00:39:28,200
Speaker 1: which those laws are changing, which is that space itself

776
00:39:28,280 --> 00:39:31,880
Speaker 1: is expanding. As you mentioned, dark energy is accelerating the

777
00:39:31,920 --> 00:39:34,880
Speaker 1: expansion of the universe, making it bigger and bigger and

778
00:39:34,960 --> 00:39:38,239
Speaker 1: changing the distances between things, and that technically is a

779
00:39:38,360 --> 00:39:41,480
Speaker 1: change in the laws of physics as a function of time,

780
00:39:41,840 --> 00:39:45,879
Speaker 1: meaning that energy is not technically conserved. It's not really

781
00:39:45,920 --> 00:39:48,800
Speaker 1: relevant for balls rolling down planes, or banana is falling

782
00:39:48,800 --> 00:39:51,839
Speaker 1: off of bookshelves, or any experiment we are going to do.

783
00:39:52,200 --> 00:39:55,040
Speaker 1: But you want the deepest understanding of energy. That turns

784
00:39:55,040 --> 00:39:58,719
Speaker 1: out in our universe it's not technically conserved but almost

785
00:39:59,080 --> 00:40:01,040
Speaker 1: right right. Well, I've feel like you're maybe cheating a

786
00:40:01,080 --> 00:40:03,480
Speaker 1: little bit here. I feel like you're saying that we

787
00:40:03,560 --> 00:40:06,719
Speaker 1: have these laws that we think described the universe, and

788
00:40:06,800 --> 00:40:10,759
Speaker 1: in them energy is conserved unless our laws are wrong,

789
00:40:10,960 --> 00:40:15,319
Speaker 1: in which case they doesn't. Does that Does that make sense?

790
00:40:15,360 --> 00:40:17,400
Speaker 1: I feel I feel like maybe what's really happening is

791
00:40:17,440 --> 00:40:19,200
Speaker 1: that we don't have the right laws of the universe,

792
00:40:19,440 --> 00:40:21,479
Speaker 1: Like we only have laws that seemed to work for

793
00:40:21,920 --> 00:40:24,399
Speaker 1: you know, moment to moment, or that doesn't take into

794
00:40:24,440 --> 00:40:27,279
Speaker 1: account to six seven of the universe. That's that's making

795
00:40:27,320 --> 00:40:30,000
Speaker 1: it expand really we just kind of maybe don't have

796
00:40:30,040 --> 00:40:32,520
Speaker 1: the right laws. It might also be that the laws

797
00:40:32,560 --> 00:40:35,719
Speaker 1: really are a function of time, right, that the way

798
00:40:35,760 --> 00:40:39,600
Speaker 1: things work changes as the universe goes on. That's just

799
00:40:39,680 --> 00:40:42,960
Speaker 1: the way the universe is. Wait, what you mean like

800
00:40:43,360 --> 00:40:45,400
Speaker 1: it's a function of something, But it's not a function

801
00:40:45,440 --> 00:40:48,080
Speaker 1: of anything. It could be a function of time, right,

802
00:40:48,200 --> 00:40:51,120
Speaker 1: But based on what law, the laws themselves could just

803
00:40:51,160 --> 00:40:53,520
Speaker 1: be a function of time, you know why. For example,

804
00:40:53,560 --> 00:40:58,080
Speaker 1: are constants constant? If the gravitational constant changed as a

805
00:40:58,120 --> 00:41:01,200
Speaker 1: function of time, then you can get free energy. If

806
00:41:01,239 --> 00:41:04,040
Speaker 1: gravity disappeared every Tuesday morning for an hour, then I could,

807
00:41:04,040 --> 00:41:06,440
Speaker 1: with no energy, take a big box of bananas and

808
00:41:06,480 --> 00:41:09,080
Speaker 1: put it on a bookshelf, and then when gravity came back,

809
00:41:09,200 --> 00:41:11,600
Speaker 1: I could knock it off and extract the energy from it.

810
00:41:11,640 --> 00:41:14,839
Speaker 1: So I'd have an infinite energy machine. If the gravitational

811
00:41:14,880 --> 00:41:18,719
Speaker 1: constant wasn't constant. So if these constants are changing, then

812
00:41:18,800 --> 00:41:22,080
Speaker 1: energy is not concerned, right, right, But it isn't that

813
00:41:22,200 --> 00:41:23,919
Speaker 1: I mean that idea what you're saying, like, hey, let's

814
00:41:23,920 --> 00:41:26,359
Speaker 1: just give up and start asking questions. Isn't that sort

815
00:41:26,360 --> 00:41:28,920
Speaker 1: of a lot of what you talk against about, right? Like,

816
00:41:28,920 --> 00:41:30,360
Speaker 1: you know, if you discovered that the laws of the

817
00:41:30,400 --> 00:41:33,120
Speaker 1: universe are changing for some unknown reason, wouldn't you want

818
00:41:33,160 --> 00:41:35,640
Speaker 1: to know what that reason was? Oh? Absolutely yes, And

819
00:41:35,760 --> 00:41:38,280
Speaker 1: doesn't mean you can't find an explanation. Right. The laws

820
00:41:38,280 --> 00:41:40,680
Speaker 1: can be changing, and those laws can be changing for

821
00:41:40,719 --> 00:41:43,280
Speaker 1: a good reason. It could be like only one consistent

822
00:41:43,280 --> 00:41:45,200
Speaker 1: way for the universe to be, and it requires these

823
00:41:45,239 --> 00:41:49,160
Speaker 1: constants to change. Right, It's still following some system which

824
00:41:49,200 --> 00:41:52,760
Speaker 1: is governing how those constants change. But the constants themselves,

825
00:41:52,840 --> 00:41:55,399
Speaker 1: the ones that describe the motion of things and how

826
00:41:55,440 --> 00:41:58,239
Speaker 1: you get equations of motion, if those are changing, then

827
00:41:58,280 --> 00:42:01,319
Speaker 1: this quantity we call energy is not conserved right, Right,

828
00:42:01,320 --> 00:42:03,279
Speaker 1: But I guess I'm saying, if there's a system that

829
00:42:03,440 --> 00:42:06,040
Speaker 1: is determining how the laws of the universe are changing,

830
00:42:06,239 --> 00:42:09,440
Speaker 1: then maybe that system is the real true you know,

831
00:42:09,480 --> 00:42:13,080
Speaker 1: a set of equations that that governed the universe. Sure, absolutely,

832
00:42:13,200 --> 00:42:16,040
Speaker 1: and they could be like the true system that governs

833
00:42:16,080 --> 00:42:19,319
Speaker 1: these laws. But the ones that determine how things move, right,

834
00:42:19,440 --> 00:42:22,160
Speaker 1: that determine motion of things through the universe. If those

835
00:42:22,239 --> 00:42:25,440
Speaker 1: laws are a function of time because they're controlled by

836
00:42:25,480 --> 00:42:28,680
Speaker 1: some super deep metal laws. Right, If those laws that

837
00:42:28,760 --> 00:42:31,520
Speaker 1: determine how things move through the universe. If those are changing,

838
00:42:31,719 --> 00:42:34,399
Speaker 1: then energy is not conserved. Well, I think we're getting

839
00:42:34,440 --> 00:42:37,200
Speaker 1: a little bit lost because we're talking about energy. I

840
00:42:37,239 --> 00:42:40,560
Speaker 1: think what you're saying is that energy is conserved if

841
00:42:40,600 --> 00:42:43,200
Speaker 1: you look at it locally, like our little you know,

842
00:42:43,239 --> 00:42:45,279
Speaker 1: what we've seen of the universe and what laws we've

843
00:42:45,320 --> 00:42:47,880
Speaker 1: coupled together. But if you look at the big, big picture,

844
00:42:48,360 --> 00:42:51,440
Speaker 1: energy is not conserved, which kind of makes you wonder,

845
00:42:51,560 --> 00:42:54,440
Speaker 1: like what it is right exactly, or throws into question

846
00:42:54,840 --> 00:42:57,799
Speaker 1: even more our ideas of it and points of the

847
00:42:57,800 --> 00:43:00,720
Speaker 1: fact that we don't really know what it is because

848
00:43:00,880 --> 00:43:03,400
Speaker 1: it's not even conservad like we thought it was exactly,

849
00:43:03,440 --> 00:43:05,920
Speaker 1: And it also questions like how important is it? One

850
00:43:05,960 --> 00:43:07,759
Speaker 1: of the reasons we thought it was important because it's

851
00:43:07,800 --> 00:43:09,440
Speaker 1: because we thought it was conserved and we thought it

852
00:43:09,480 --> 00:43:12,440
Speaker 1: was a deep truth in the universe. It revealed something fundamental.

853
00:43:12,719 --> 00:43:15,359
Speaker 1: If it's not actually conserved, you mean, it's maybe not

854
00:43:15,440 --> 00:43:20,200
Speaker 1: as important as we thought, right right, It points like

855
00:43:20,239 --> 00:43:23,160
Speaker 1: maybe it's just the pawn in the meadow law of

856
00:43:23,239 --> 00:43:26,360
Speaker 1: the universe that we have no idea about so far exactly.

857
00:43:26,440 --> 00:43:28,440
Speaker 1: It's just like a lowly fruit, like a cherry instead

858
00:43:28,480 --> 00:43:32,480
Speaker 1: of the regal banana instead of the legal banana, exactly,

859
00:43:32,880 --> 00:43:35,919
Speaker 1: the all important banana. Yes, all right, well let's get

860
00:43:36,000 --> 00:43:38,719
Speaker 1: into a little bit more about what we don't know

861
00:43:38,719 --> 00:43:42,479
Speaker 1: about the definition of energy and what it could all mean. Man,

862
00:43:43,480 --> 00:43:58,280
Speaker 1: But first let's take another quick break. All right, welcome

863
00:43:58,280 --> 00:44:02,239
Speaker 1: back to Daniel and Jorge argue about energy when one

864
00:44:02,280 --> 00:44:04,000
Speaker 1: of us is a physicist and the other one is

865
00:44:04,040 --> 00:44:09,000
Speaker 1: not clearly, but I guess I'm getting the picture that,

866
00:44:09,040 --> 00:44:11,640
Speaker 1: you know, we kind of thought we knew what energy was.

867
00:44:11,800 --> 00:44:14,120
Speaker 1: We thought it was this fundamental thing that always seems

868
00:44:14,160 --> 00:44:16,680
Speaker 1: to be conserved. But it turns out that it's not

869
00:44:16,719 --> 00:44:19,799
Speaker 1: always conserved. So now maybe it's not only do we

870
00:44:19,840 --> 00:44:22,640
Speaker 1: not know what it is, but maybe it's not even fundamental. Yeah,

871
00:44:22,680 --> 00:44:25,799
Speaker 1: that's right, And it's sort of disappointing because even a

872
00:44:25,920 --> 00:44:29,200
Speaker 1: small amount of non conservation means it's just not conserved.

873
00:44:29,480 --> 00:44:31,400
Speaker 1: You know, there's like two things, things are conserved and

874
00:44:31,440 --> 00:44:33,880
Speaker 1: things that are not. There's a whole bunch of categories

875
00:44:33,880 --> 00:44:36,640
Speaker 1: of things that are not conserved, and being almost conserved

876
00:44:36,920 --> 00:44:39,960
Speaker 1: means I guess you're important, but not really truly fundamental.

877
00:44:40,120 --> 00:44:43,240
Speaker 1: All right, Well, then what would you say energy is then?

878
00:44:43,320 --> 00:44:45,560
Speaker 1: I would say, I wish I knew, and it's something

879
00:44:45,600 --> 00:44:49,080
Speaker 1: definitely deep and interesting in the universe, right, It's something

880
00:44:49,120 --> 00:44:51,960
Speaker 1: that is almost conserved, and it can slash back and

881
00:44:52,000 --> 00:44:54,799
Speaker 1: forth between these two different kind of things that feel very,

882
00:44:54,920 --> 00:44:58,120
Speaker 1: very different. What is energy? The philosophical question really is

883
00:44:58,320 --> 00:45:01,080
Speaker 1: what do kinetic and potential energy have in common? What

884
00:45:01,120 --> 00:45:03,960
Speaker 1: are they part of when you put them together in

885
00:45:04,000 --> 00:45:06,279
Speaker 1: the same way that like you can put electricity and

886
00:45:06,320 --> 00:45:09,920
Speaker 1: magnetism together into a holistic thing and get an understanding

887
00:45:09,920 --> 00:45:13,279
Speaker 1: of electromagnetism, You're like, oh, that explains this and that

888
00:45:13,360 --> 00:45:15,560
Speaker 1: and brings all these ideas together. You have a feeling

889
00:45:15,600 --> 00:45:17,960
Speaker 1: of having an answer. If we understood how kinetic energy

890
00:45:18,040 --> 00:45:20,719
Speaker 1: and potential energy you fit together into one holistic thing,

891
00:45:21,080 --> 00:45:23,480
Speaker 1: we'll be able to grapple better with this question. I

892
00:45:23,480 --> 00:45:25,840
Speaker 1: feel like you're saying, like, maybe even the word energy

893
00:45:25,920 --> 00:45:29,400
Speaker 1: is a little distracting from the real question, which is

894
00:45:29,440 --> 00:45:32,800
Speaker 1: like why is there a relationship between you know, motion

895
00:45:33,239 --> 00:45:36,359
Speaker 1: and potential in a way, or even like why does

896
00:45:36,400 --> 00:45:38,960
Speaker 1: potential exists at all? Exactly? And you can try to

897
00:45:39,000 --> 00:45:41,280
Speaker 1: tease it apart by looking at the equations of motion

898
00:45:41,760 --> 00:45:44,239
Speaker 1: and thing like what is it that defines how things

899
00:45:44,320 --> 00:45:47,680
Speaker 1: move and why can this weird quantity slash back and forth.

900
00:45:48,080 --> 00:45:49,760
Speaker 1: And one way to get a little bit of insight

901
00:45:49,800 --> 00:45:53,200
Speaker 1: into it is to understand that potential really is also

902
00:45:53,239 --> 00:45:57,160
Speaker 1: about motion, Like potential energy is what causes forces. Right,

903
00:45:57,239 --> 00:46:00,239
Speaker 1: the reason that the banana falls off the book shelf

904
00:46:00,280 --> 00:46:03,480
Speaker 1: and accelerates towards the floor is because there's a gravitational

905
00:46:03,560 --> 00:46:06,560
Speaker 1: force there. There's a force there because there's a difference

906
00:46:06,680 --> 00:46:08,759
Speaker 1: in the potential. So you can think about in terms

907
00:46:08,760 --> 00:46:11,279
Speaker 1: of kinetic energy and potential energy. You can also think

908
00:46:11,320 --> 00:46:14,480
Speaker 1: about it in terms of like motion and forces. Like

909
00:46:14,520 --> 00:46:17,040
Speaker 1: a particle just flying through the universe, it just has

910
00:46:17,080 --> 00:46:21,400
Speaker 1: kinetic energy. Now add other particles interacting with it, putting

911
00:46:21,440 --> 00:46:25,080
Speaker 1: forces on it. Those are creating potential energy for that particle.

912
00:46:25,239 --> 00:46:28,279
Speaker 1: In some sense, it's not kinetic energy and potential energy.

913
00:46:28,280 --> 00:46:32,400
Speaker 1: It's kinetic energy and other forces changing its kinetic energy.

914
00:46:33,120 --> 00:46:34,879
Speaker 1: I think what you're saying is that maybe there's really

915
00:46:34,880 --> 00:46:40,560
Speaker 1: only motion and potential motion, Like there's only motion in

916
00:46:40,600 --> 00:46:43,120
Speaker 1: the universe, and then there's what happens when two things

917
00:46:43,120 --> 00:46:46,360
Speaker 1: that have motion kind of bump into each other somehow,

918
00:46:46,400 --> 00:46:49,239
Speaker 1: for some reason, they interact in a way that creates potential,

919
00:46:49,520 --> 00:46:52,400
Speaker 1: but really you're just talking about motion and what happens

920
00:46:52,680 --> 00:46:55,680
Speaker 1: in that interaction exactly. And this is the philosophical process

921
00:46:55,880 --> 00:46:58,959
Speaker 1: of sort of stumbling towards a deeper concept or trying

922
00:46:58,960 --> 00:47:01,959
Speaker 1: to understand what these things have in common and generalize

923
00:47:01,960 --> 00:47:04,640
Speaker 1: it into an idea that really fits together that can

924
00:47:04,719 --> 00:47:07,000
Speaker 1: hold as a bucket all these different concepts that we

925
00:47:07,040 --> 00:47:09,480
Speaker 1: consider energy and its properties. And it's connected to this

926
00:47:09,560 --> 00:47:12,200
Speaker 1: other question we talked about, like our fields. Real well,

927
00:47:12,200 --> 00:47:13,879
Speaker 1: it sort of sounds like you're saying that maybe there's

928
00:47:13,960 --> 00:47:17,520
Speaker 1: only really kinetic energy, right, Like, there's only kinetic energy,

929
00:47:17,600 --> 00:47:19,400
Speaker 1: and there's also what happens when two things that have

930
00:47:19,480 --> 00:47:23,120
Speaker 1: kinetic energy interact with each other, right, Like, it sounds

931
00:47:23,160 --> 00:47:28,120
Speaker 1: like maybe potential energy is really just about motion and interactions,

932
00:47:28,200 --> 00:47:29,799
Speaker 1: and so you've got to ask, like, why does the

933
00:47:29,880 --> 00:47:32,600
Speaker 1: universe have motion and why does it have interactions? Like

934
00:47:32,800 --> 00:47:35,640
Speaker 1: right right, if it didn't have interactions, everyone would just

935
00:47:35,680 --> 00:47:38,839
Speaker 1: fly around by themselves. They would just be kinetic energy

936
00:47:38,880 --> 00:47:41,640
Speaker 1: and that would never change. But it changes because we

937
00:47:41,760 --> 00:47:44,080
Speaker 1: have these interactions in the universe. And that goes to

938
00:47:44,160 --> 00:47:46,439
Speaker 1: like an even more abstract question, which is like why

939
00:47:46,440 --> 00:47:49,439
Speaker 1: do you consider things is interacting. That assumes that there's

940
00:47:49,520 --> 00:47:51,799
Speaker 1: different things that you can say, like there's this one

941
00:47:51,840 --> 00:47:54,200
Speaker 1: thing and the other thing, Well, how do you draw

942
00:47:54,239 --> 00:47:56,200
Speaker 1: the line between them? Right, it's like one half of

943
00:47:56,200 --> 00:47:58,280
Speaker 1: the earth interacting with the other half of the earth.

944
00:47:58,400 --> 00:48:00,239
Speaker 1: How do you slice that? Why do you call the

945
00:48:00,239 --> 00:48:02,879
Speaker 1: earth one thing and not two things? And anytime your

946
00:48:02,960 --> 00:48:06,480
Speaker 1: ideas are based on totally arbitrary designations like that, like

947
00:48:06,560 --> 00:48:08,239
Speaker 1: this is a thing, but that's not a thing, or

948
00:48:08,239 --> 00:48:10,200
Speaker 1: this is two things, then you know that you're looking

949
00:48:10,200 --> 00:48:12,480
Speaker 1: at it the wrong way. I think the work that's

950
00:48:12,520 --> 00:48:14,359
Speaker 1: left to be done is to understand this as one

951
00:48:14,400 --> 00:48:17,120
Speaker 1: holistic thing. You know, what is it really that's flowing

952
00:48:17,160 --> 00:48:20,040
Speaker 1: between two objects where one is in motion and then

953
00:48:20,080 --> 00:48:22,319
Speaker 1: another one is in motion. How is that flowing? Is

954
00:48:22,320 --> 00:48:24,480
Speaker 1: it really changing into a different kind of energy? Or

955
00:48:24,560 --> 00:48:27,440
Speaker 1: is there one holistic, super kind of idea there that

956
00:48:27,560 --> 00:48:30,920
Speaker 1: you can understand connects these two things right? Right, Like

957
00:48:30,960 --> 00:48:33,879
Speaker 1: maybe there aren't humans and zombies. Maybe maybe we're all

958
00:48:33,920 --> 00:48:39,520
Speaker 1: just human and zombies just have the potential to eat humans. Exactly.

959
00:48:39,560 --> 00:48:42,040
Speaker 1: Maybe before you eat the banana, the banana is already

960
00:48:42,080 --> 00:48:44,760
Speaker 1: kind of party, you you know, or hey, plus banana

961
00:48:44,800 --> 00:48:47,640
Speaker 1: is already the thing before you eat the banana. I

962
00:48:47,640 --> 00:48:49,440
Speaker 1: think what you're saying is that, you know, we talk

963
00:48:49,480 --> 00:48:52,120
Speaker 1: about kinnetic energy and potential energy, but really maybe there's

964
00:48:52,200 --> 00:48:56,160
Speaker 1: just part of the same thing, like motion plus interactions. Right.

965
00:48:56,200 --> 00:48:58,160
Speaker 1: If I zoom in on a particle on like a proton,

966
00:48:58,239 --> 00:49:00,880
Speaker 1: and say, oh, look, those quirks have kinnectic energy inside

967
00:49:00,880 --> 00:49:02,359
Speaker 1: of them. But if I zoom out and just look

968
00:49:02,360 --> 00:49:04,040
Speaker 1: at the proton, I'm like, oh no, the proton is

969
00:49:04,080 --> 00:49:06,359
Speaker 1: at rest. It has no kinetic energy. So how much

970
00:49:06,440 --> 00:49:09,080
Speaker 1: kinetic energy there is depends on what I'm defining to

971
00:49:09,120 --> 00:49:11,960
Speaker 1: be a thing or not. It seems sort of arbitrary,

972
00:49:12,000 --> 00:49:14,040
Speaker 1: and I think that's the biggest clue that will lead

973
00:49:14,120 --> 00:49:16,279
Speaker 1: us to a deeper understanding of energy, but I don't

974
00:49:16,320 --> 00:49:18,759
Speaker 1: have that understanding today. Well, let's touch a little bit

975
00:49:18,800 --> 00:49:21,600
Speaker 1: into that the scenario that you mentioned earlier in the episode,

976
00:49:21,640 --> 00:49:24,520
Speaker 1: which is the end of the universe, and that maybe

977
00:49:24,520 --> 00:49:26,959
Speaker 1: one potential end of the universe is the heat death

978
00:49:27,000 --> 00:49:31,000
Speaker 1: of the universe, where you know, everything has energy, but

979
00:49:31,120 --> 00:49:34,640
Speaker 1: nothing can happen everything. You know, particles are moving like

980
00:49:34,680 --> 00:49:37,880
Speaker 1: a giant gas, and so there's definitely energy there, but

981
00:49:38,000 --> 00:49:40,839
Speaker 1: no potential energy is that what you're saying that there's

982
00:49:40,840 --> 00:49:44,880
Speaker 1: it's an scenario where there's no potential energy left in

983
00:49:44,920 --> 00:49:48,279
Speaker 1: the universe. Yeah, there's useful energy, and then there's sort

984
00:49:48,320 --> 00:49:52,359
Speaker 1: of useless energy. Useful energy is energy you can use

985
00:49:52,480 --> 00:49:55,640
Speaker 1: to do work, to like move something up a potential

986
00:49:55,719 --> 00:49:57,840
Speaker 1: for example. And you know if you have energy in

987
00:49:57,880 --> 00:50:00,360
Speaker 1: a battery, you can take that energy and use it

988
00:50:00,360 --> 00:50:02,399
Speaker 1: to power and engine and it can like push your

989
00:50:02,400 --> 00:50:04,560
Speaker 1: banana up off the floor back to the top of

990
00:50:04,600 --> 00:50:07,680
Speaker 1: the bookshelf. That's useful energy, and that only happens when

991
00:50:07,680 --> 00:50:12,200
Speaker 1: you have energy localized somewhere, right, when you have low entropy,

992
00:50:12,280 --> 00:50:16,360
Speaker 1: when there's organization of stuff. Opposite of that is useless energy.

993
00:50:16,480 --> 00:50:19,360
Speaker 1: Energy like heat. If everything is just hot and everything

994
00:50:19,440 --> 00:50:22,400
Speaker 1: is the same temperature, there's no temperature difference, there's no

995
00:50:22,560 --> 00:50:25,360
Speaker 1: energy gredients. You can't use that to power and engine.

996
00:50:25,800 --> 00:50:27,400
Speaker 1: Like if you have an engine and you're in a

997
00:50:27,600 --> 00:50:30,440
Speaker 1: universe where everything is smooth but hot, there's no way

998
00:50:30,480 --> 00:50:32,600
Speaker 1: to take that energy in those motions of the particles

999
00:50:32,600 --> 00:50:35,400
Speaker 1: and turn that into something useful. So the key idea

1000
00:50:35,440 --> 00:50:38,960
Speaker 1: there's entropy. Entropy, right, Yeah, there's like everything is that

1001
00:50:39,480 --> 00:50:42,600
Speaker 1: a hot mess? What you're saying a bland, hot mess.

1002
00:50:42,600 --> 00:50:44,880
Speaker 1: But wouldn't I guess even invest in an area, wouldn't

1003
00:50:44,880 --> 00:50:49,680
Speaker 1: gravity eventually kind of bring stuff together, creating potential energy?

1004
00:50:50,000 --> 00:50:52,480
Speaker 1: Or like, how does gravity disappear in this scenario? And

1005
00:50:52,480 --> 00:50:55,040
Speaker 1: gravity doesn't disappear, but it can't do anything in that

1006
00:50:55,080 --> 00:50:59,200
Speaker 1: scenario because everything is smooth and homogeneous. Gravity requires some

1007
00:50:59,360 --> 00:51:02,400
Speaker 1: clump to get things started. Like in the early universe,

1008
00:51:02,560 --> 00:51:05,360
Speaker 1: we didn't have a smooth and homogeneous blob of stuff

1009
00:51:05,360 --> 00:51:08,359
Speaker 1: in the very beginning. We had little quantum fluctuations, little

1010
00:51:08,360 --> 00:51:11,880
Speaker 1: bits of over density and under density that gravity grabbed

1011
00:51:11,920 --> 00:51:15,160
Speaker 1: onto and exaggerated. But if you have the true heat

1012
00:51:15,160 --> 00:51:17,400
Speaker 1: death of the universe, where everything is spread out equally,

1013
00:51:17,480 --> 00:51:21,000
Speaker 1: then every particle feels the same gravitational pull in every direction,

1014
00:51:21,280 --> 00:51:24,200
Speaker 1: so it basically cancels out. What is this idea of entropy?

1015
00:51:24,640 --> 00:51:27,840
Speaker 1: How does that impact our definition of energy? Like maybe

1016
00:51:27,920 --> 00:51:30,600
Speaker 1: it's not real or something. Well, folks who love and

1017
00:51:30,680 --> 00:51:33,760
Speaker 1: understand them, dynamics have different definitions of energy. There's energy

1018
00:51:33,760 --> 00:51:36,640
Speaker 1: in general, and then there's free energy, which is sort

1019
00:51:36,640 --> 00:51:39,600
Speaker 1: of like an energy available to do useful work. And

1020
00:51:39,640 --> 00:51:43,240
Speaker 1: then there's also discount of energy and energy on sale.

1021
00:51:43,440 --> 00:51:45,800
Speaker 1: And then there's free lunch, which apparently doesn't even exist

1022
00:51:47,600 --> 00:51:49,319
Speaker 1: that we know of. But you, as you said, the

1023
00:51:49,400 --> 00:51:51,680
Speaker 1: universe is changing, Daniel. Maybe it will be free lunch

1024
00:51:51,680 --> 00:51:54,160
Speaker 1: in the future for everyone. That's right, And these topics

1025
00:51:54,200 --> 00:51:57,160
Speaker 1: always make me uncomfortable. Thermodynamics is the topic of physics

1026
00:51:57,280 --> 00:51:59,400
Speaker 1: that I avoided as much as possible when I was

1027
00:51:59,440 --> 00:52:03,120
Speaker 1: taking class. Is right? That and zombie movies? Or maybe

1028
00:52:03,120 --> 00:52:05,919
Speaker 1: they're about the same thing, right, Zombies are about decay

1029
00:52:06,000 --> 00:52:10,680
Speaker 1: and things breaking down. Maybe maybe this is all turned

1030
00:52:10,680 --> 00:52:14,360
Speaker 1: out to be a deep psychological journey into daniel psyche.

1031
00:52:14,520 --> 00:52:17,600
Speaker 1: That's right, but we're understanding the conservation of Daniel's decisions.

1032
00:52:19,080 --> 00:52:22,879
Speaker 1: Zombies and entropy make you uncomfortable. Maybe we should dig

1033
00:52:22,880 --> 00:52:25,759
Speaker 1: deeper into that day and did something happen in your childhood? Yes,

1034
00:52:25,760 --> 00:52:28,040
Speaker 1: a zombie came an intropute in my bedroom when I

1035
00:52:28,080 --> 00:52:31,880
Speaker 1: was a kid that I'm scared. No. Thermodynamics to me

1036
00:52:32,040 --> 00:52:34,600
Speaker 1: is complicated because you're just so many particles. It's all

1037
00:52:34,600 --> 00:52:37,960
Speaker 1: about statistical statements of large systems of particles. For me,

1038
00:52:38,000 --> 00:52:41,400
Speaker 1: it's easier to grapple with one particle bouncing off another particle,

1039
00:52:41,440 --> 00:52:43,480
Speaker 1: because I would like to get down to the microscopic

1040
00:52:43,520 --> 00:52:46,480
Speaker 1: picture what's really happening, and there amo dynamics is about

1041
00:52:46,480 --> 00:52:48,840
Speaker 1: like zooming out and trying to make like broad statements

1042
00:52:48,840 --> 00:52:52,560
Speaker 1: about systems. It's not the same as philosophy though, Yeah,

1043
00:52:52,640 --> 00:52:57,200
Speaker 1: but philosophy nobody has any wrong answers. That's right, it's

1044
00:52:57,239 --> 00:53:01,680
Speaker 1: not verifiable, how convenient. Well, I think the overall picture

1045
00:53:01,680 --> 00:53:04,320
Speaker 1: I'm getting is that to answer the question what is energy,

1046
00:53:04,440 --> 00:53:07,880
Speaker 1: it's it's tough. You know, we have different labels for it.

1047
00:53:07,920 --> 00:53:10,600
Speaker 1: There's kinetic energy, that it's potential energy. That seems to

1048
00:53:10,640 --> 00:53:13,719
Speaker 1: be all about there is to it, but that's not

1049
00:53:13,800 --> 00:53:16,200
Speaker 1: the full picture. Like it seems to be conserved, but

1050
00:53:16,239 --> 00:53:18,759
Speaker 1: it's not really conserved in the universe, and so maybe

1051
00:53:18,800 --> 00:53:20,600
Speaker 1: it's not even an important thing, or maybe it's not

1052
00:53:20,640 --> 00:53:22,960
Speaker 1: even a thing. Like maybe in the future aliens will

1053
00:53:22,960 --> 00:53:25,040
Speaker 1: be like, why do you guys were thinking about energy?

1054
00:53:25,400 --> 00:53:28,440
Speaker 1: That's like thinking about the ether or thinking about you know,

1055
00:53:28,600 --> 00:53:31,520
Speaker 1: the soul or something like. That's that's a that's the

1056
00:53:31,560 --> 00:53:34,040
Speaker 1: thing that doesn't make sense. Yeah, it definitely is driven

1057
00:53:34,040 --> 00:53:36,879
Speaker 1: from an intuitive experience of the world, and then try

1058
00:53:36,880 --> 00:53:39,319
Speaker 1: to extrapolate that to physics and understand if it makes

1059
00:53:39,320 --> 00:53:41,479
Speaker 1: sense and it's sort of kind of seems like it does,

1060
00:53:41,560 --> 00:53:44,080
Speaker 1: but maybe it doesn't quite. We definitely still have work

1061
00:53:44,120 --> 00:53:45,640
Speaker 1: to do. And you know, if you look into a

1062
00:53:45,640 --> 00:53:48,160
Speaker 1: physics book or google this question, you might find some

1063
00:53:48,200 --> 00:53:51,200
Speaker 1: confusing answers. Some of them are things like energy is

1064
00:53:51,239 --> 00:53:54,920
Speaker 1: the quantity that's conserved if the laws of physics don't change,

1065
00:53:55,120 --> 00:53:58,040
Speaker 1: So they're like defining it to be the conserved thing,

1066
00:53:58,440 --> 00:54:01,000
Speaker 1: which doesn't really tell you like what it is. It

1067
00:54:01,080 --> 00:54:04,280
Speaker 1: just tells you how Nuther's theorem impacts these laws of physics.

1068
00:54:04,280 --> 00:54:06,279
Speaker 1: Doesn't really tell you like what it is. I think

1069
00:54:06,280 --> 00:54:09,839
Speaker 1: we're still struggling to figure out exactly what energy is, right,

1070
00:54:09,920 --> 00:54:12,040
Speaker 1: it might need to be redefined now that we sort

1071
00:54:12,080 --> 00:54:13,799
Speaker 1: of know and this is the only reason that we

1072
00:54:13,840 --> 00:54:16,120
Speaker 1: know that the universe is changing and the laws of

1073
00:54:16,120 --> 00:54:18,880
Speaker 1: physics are not constant. Ye, so the history of this

1074
00:54:19,000 --> 00:54:21,600
Speaker 1: scene over a few hundred years is like discovery of

1075
00:54:21,640 --> 00:54:24,279
Speaker 1: kinetic energy that seems to be conserved. Oops, no, it's

1076
00:54:24,320 --> 00:54:27,799
Speaker 1: not only kinetic energy plus potential energy is conserved. And

1077
00:54:27,800 --> 00:54:30,799
Speaker 1: then Einstein's general relativity as a whole new system for

1078
00:54:30,840 --> 00:54:33,160
Speaker 1: the universe and not there says hold on a second,

1079
00:54:33,400 --> 00:54:36,280
Speaker 1: that doesn't guarantee conservation of energy, so people like, oops,

1080
00:54:36,360 --> 00:54:39,160
Speaker 1: better patch that up, make sure conserve energy, and then

1081
00:54:39,160 --> 00:54:42,880
Speaker 1: we discover actually, it doesn't conserve energy. The universe disagrees

1082
00:54:42,920 --> 00:54:45,200
Speaker 1: with that whole idea. So it's been a lot of

1083
00:54:45,200 --> 00:54:48,040
Speaker 1: back and forth. Yeah, I'm amazing you guys still have

1084
00:54:48,040 --> 00:54:50,880
Speaker 1: the energy to keep at it. Well, somebody keeps eating bananas,

1085
00:54:50,880 --> 00:54:53,359
Speaker 1: and so we keep asking questions. Right, maybe we've been

1086
00:54:53,400 --> 00:54:59,240
Speaker 1: as our concerned. Well, it seems like maybe we won't

1087
00:54:59,239 --> 00:55:02,239
Speaker 1: define it any time soon. But I think it sort

1088
00:55:02,239 --> 00:55:04,439
Speaker 1: of points to the idea that there are these deep

1089
00:55:04,840 --> 00:55:10,560
Speaker 1: relationships in the universe between motion and and potential and fields,

1090
00:55:10,719 --> 00:55:13,160
Speaker 1: and we're still trying to figure out what those relationships

1091
00:55:13,200 --> 00:55:15,360
Speaker 1: are because that kind of tells that's what's going to

1092
00:55:15,440 --> 00:55:18,080
Speaker 1: tell us what the true nature of the universe is. Yeah,

1093
00:55:18,120 --> 00:55:20,120
Speaker 1: and one of the deepest goals in physics is to

1094
00:55:20,239 --> 00:55:23,360
Speaker 1: come up with a concise, mathematical story about how the

1095
00:55:23,440 --> 00:55:26,560
Speaker 1: universe works in a way that makes sense to us.

1096
00:55:27,080 --> 00:55:29,200
Speaker 1: And that's what we're struggling with here, is connecting these

1097
00:55:29,200 --> 00:55:33,200
Speaker 1: mathematical concepts with intuitive ideas that gel with us, that

1098
00:55:33,320 --> 00:55:36,239
Speaker 1: tell us something about the nature of the universe more

1099
00:55:36,280 --> 00:55:38,680
Speaker 1: than just looking at the black and white equations on

1100
00:55:38,719 --> 00:55:41,560
Speaker 1: a page. And that's what it's all about, jelling with

1101
00:55:41,600 --> 00:55:45,279
Speaker 1: the universe and eat a banana and Jill and chill

1102
00:55:45,280 --> 00:55:47,759
Speaker 1: out exactly, But don't eat the last banana because it's

1103
00:55:47,800 --> 00:55:49,600
Speaker 1: a fixed number of them in the universe. And if

1104
00:55:49,600 --> 00:55:51,400
Speaker 1: you eat the last one or he can't, and then

1105
00:55:51,400 --> 00:55:53,399
Speaker 1: we won't have any more partner. Know, it's an ever

1106
00:55:53,560 --> 00:55:56,560
Speaker 1: green quantity, right, that's what I thought. That's what we concluded. No,

1107
00:55:57,000 --> 00:55:59,280
Speaker 1: I see, eat all the bananas you want, ran because

1108
00:55:59,600 --> 00:56:03,480
Speaker 1: somewhere or some unknown process is recreating them. That's a

1109
00:56:03,560 --> 00:56:07,200
Speaker 1: nice universe to live in. Yeah, pretty bananas. All right. Well,

1110
00:56:07,200 --> 00:56:09,560
Speaker 1: we hope you enjoyed that discussion. Thanks for joining us,

1111
00:56:10,320 --> 00:56:20,319
Speaker 1: see you next time. Thanks for listening, and remember that

1112
00:56:20,440 --> 00:56:23,200
Speaker 1: Daniel and Jorge explained. The universe is a production of

1113
00:56:23,280 --> 00:56:26,640
Speaker 1: I Heart Radio. For more podcast for my heart Radio,

1114
00:56:26,800 --> 00:56:30,360
Speaker 1: visit the I heart Radio app, Apple Podcasts, or wherever

1115
00:56:30,480 --> 00:56:37,919
Speaker 1: you listen to your favorite shows. Yeah,