1
00:00:00,080 --> 00:00:02,960
Speaker 1: If you love iPhone, you'll love Apple Card. It's the

2
00:00:03,040 --> 00:00:06,920
Speaker 1: credit card designed for iPhone. It gives you unlimited daily

3
00:00:07,040 --> 00:00:10,000
Speaker 1: cash back that can earn four point four zero percent

4
00:00:10,160 --> 00:00:12,960
Speaker 1: annual percentage yield. When you open a high Yield savings

5
00:00:13,000 --> 00:00:16,280
Speaker 1: account through Apple Card, apply for Applecard in the wallet

6
00:00:16,280 --> 00:00:19,520
Speaker 1: app subject to credit approval. Savings is available to Apple

7
00:00:19,560 --> 00:00:22,800
Speaker 1: Card owners subject to eligibility. Apple Card and Savings by

8
00:00:22,840 --> 00:00:26,120
Speaker 1: Goldman Sachs Bank USA, Salt Lake City Branch, Member FDIC,

9
00:00:26,520 --> 00:00:29,280
Speaker 1: terms and more at applecard dot com. When you pop

10
00:00:29,320 --> 00:00:31,240
Speaker 1: a piece of cheese into your mouth, you're probably not

11
00:00:31,360 --> 00:00:34,280
Speaker 1: thinking about the environmental impact. But the people in the

12
00:00:34,360 --> 00:00:37,680
Speaker 1: dairy industry are. That's why they're working hard every day

13
00:00:37,720 --> 00:00:40,760
Speaker 1: to find new ways to reduce waste, conserve natural resources,

14
00:00:40,800 --> 00:00:44,360
Speaker 1: and drive down greenhouse gas emissions. How is US Dairy

15
00:00:44,400 --> 00:00:48,520
Speaker 1: tackling greenhouse gases? Many farms use anaerobic digesters to turn

16
00:00:48,560 --> 00:00:53,080
Speaker 1: the methane from manure into renewable energy that can power farms, towns,

17
00:00:53,120 --> 00:00:57,240
Speaker 1: and electric cars. Visit us dairy dot COM's Last Sustainability

18
00:00:57,280 --> 00:00:58,000
Speaker 1: to learn more.

19
00:00:58,760 --> 00:00:59,760
Speaker 2: Guess what well, what's that?

20
00:00:59,840 --> 00:01:01,720
Speaker 3: Ma I go? I've been trying to write a promo

21
00:01:01,840 --> 00:01:04,440
Speaker 3: for our podcast, Part Time Genius, But even though we've

22
00:01:04,440 --> 00:01:06,080
Speaker 3: done over two hundred and fifty.

23
00:01:05,800 --> 00:01:09,240
Speaker 4: Episodes, we don't really talk about murders or cults. I mean,

24
00:01:09,280 --> 00:01:11,600
Speaker 4: we did just cover the Illuminati of cheese, so I

25
00:01:11,600 --> 00:01:14,240
Speaker 4: feel like that makes us pretty edgy. We also solve

26
00:01:14,319 --> 00:01:17,600
Speaker 4: mysteries like how Chinese is your Chinese food? And how

27
00:01:17,600 --> 00:01:20,400
Speaker 4: do dollar stores make money? And then of course can

28
00:01:20,440 --> 00:01:21,759
Speaker 4: you game a dog show?

29
00:01:22,040 --> 00:01:24,360
Speaker 2: So what you're saying is everyone should be listening.

30
00:01:24,720 --> 00:01:27,080
Speaker 4: Listen to Part Time Genius on the iHeartRadio app or

31
00:01:27,120 --> 00:01:28,720
Speaker 4: wherever you get your podcasts.

32
00:01:29,160 --> 00:01:32,680
Speaker 5: Hi, I'm David Eagleman from the podcast Inner Cosmos, which

33
00:01:32,720 --> 00:01:35,720
Speaker 5: recently hit the number one science podcast in America. I

34
00:01:35,760 --> 00:01:39,480
Speaker 5: mean neuroscientists at Stanford and I've spent my career exploring

35
00:01:39,560 --> 00:01:41,720
Speaker 5: the three pound universe in our heads.

36
00:01:42,040 --> 00:01:45,160
Speaker 2: Join me weekly to explore the relationship.

37
00:01:44,440 --> 00:01:47,440
Speaker 5: Between your brain and your life, because the more we

38
00:01:47,520 --> 00:01:50,200
Speaker 5: know about what's running under the hood, bet or we

39
00:01:50,240 --> 00:01:53,760
Speaker 5: can steer our lives. Listen to Inner Cosmos with David

40
00:01:53,800 --> 00:01:57,280
Speaker 5: Eagleman on the iHeartRadio app, Apple podcasts or wherever you

41
00:01:57,320 --> 00:01:58,440
Speaker 5: get your podcasts.

42
00:02:00,200 --> 00:02:02,240
Speaker 3: Hey, it's Horehan Daniel here, and we want to tell

43
00:02:02,240 --> 00:02:03,400
Speaker 3: you about our new book.

44
00:02:03,520 --> 00:02:07,280
Speaker 1: It's called Frequently Asked Questions about the Universe.

45
00:02:07,000 --> 00:02:09,280
Speaker 3: Because you have questions about the universe, and so we

46
00:02:09,360 --> 00:02:11,240
Speaker 3: decided to write a book all about them.

47
00:02:11,320 --> 00:02:13,720
Speaker 1: We talk about your questions, we give some answers, we

48
00:02:13,800 --> 00:02:15,519
Speaker 1: make a bunch of silly jokes.

49
00:02:15,440 --> 00:02:18,200
Speaker 3: As usual, and we tackle all kinds of questions, including

50
00:02:18,280 --> 00:02:20,760
Speaker 3: what happens if I fall into a black hole? Or

51
00:02:20,919 --> 00:02:23,160
Speaker 3: is there another version of you out there that's right?

52
00:02:23,280 --> 00:02:27,120
Speaker 1: Like usual, we tackle the deepest, darkest, biggest, craziest questions

53
00:02:27,120 --> 00:02:28,800
Speaker 1: about this incredible cosmos.

54
00:02:28,880 --> 00:02:30,680
Speaker 3: If you want to support the podcast, please get the

55
00:02:30,680 --> 00:02:32,760
Speaker 3: book and get a copy, not just for yourself, but

56
00:02:33,040 --> 00:02:38,040
Speaker 3: you know, for your nieces and nephews, cousins, friends, parents, dogs, hamsters,

57
00:02:38,280 --> 00:02:39,640
Speaker 3: and for the aliens.

58
00:02:39,720 --> 00:02:43,520
Speaker 1: So get your copy of Frequently Asked Questions about the Universe.

59
00:02:43,639 --> 00:02:46,679
Speaker 1: It's available for pre order now, coming out November two.

60
00:02:46,919 --> 00:02:49,760
Speaker 1: You can find more details at the book's website, universe

61
00:02:49,919 --> 00:02:53,000
Speaker 1: faq dot com. Thanks for your support, and.

62
00:02:52,960 --> 00:02:55,040
Speaker 3: If you have a hamster that can read, please let

63
00:02:55,080 --> 00:03:07,680
Speaker 3: us know. We'd love to have them on the podcast. Hey, Daniel,

64
00:03:07,680 --> 00:03:09,400
Speaker 3: I have a question for you about time.

65
00:03:09,680 --> 00:03:11,680
Speaker 1: All right? I got time for that, all right?

66
00:03:11,720 --> 00:03:13,880
Speaker 3: So you do a lot of things, right, you're a professor,

67
00:03:14,000 --> 00:03:17,160
Speaker 3: you have a podcast, and you're always switching between them.

68
00:03:17,560 --> 00:03:20,359
Speaker 1: That's true. It's a lot of different things to manage.

69
00:03:20,000 --> 00:03:22,400
Speaker 3: All right. So then what do you think is the

70
00:03:22,520 --> 00:03:26,800
Speaker 3: shortest useful unit of time? Like, can you get something

71
00:03:26,840 --> 00:03:29,480
Speaker 3: done in five minutes? Or do you need like an

72
00:03:29,520 --> 00:03:31,240
Speaker 3: hour just to dig into something?

73
00:03:31,400 --> 00:03:33,600
Speaker 1: Well, you know, it sort of depends on what it is.

74
00:03:33,600 --> 00:03:36,800
Speaker 1: Is it serious research or just like writing bad jokes

75
00:03:36,800 --> 00:03:37,520
Speaker 1: for the podcast?

76
00:03:38,160 --> 00:03:41,040
Speaker 3: What do you mean? All right? Well, which one takes

77
00:03:41,040 --> 00:03:41,600
Speaker 3: more time?

78
00:03:41,760 --> 00:03:43,960
Speaker 1: Oh? Bad jokes for sure. I mean at some point

79
00:03:44,240 --> 00:03:46,400
Speaker 1: you just can't scrape that barrel any deeper.

80
00:03:46,440 --> 00:03:47,600
Speaker 3: What if you just give you more time?

81
00:03:47,640 --> 00:03:49,760
Speaker 1: As long as you're writing jokes about time, they basically

82
00:03:49,800 --> 00:03:50,720
Speaker 1: just write themselves.

83
00:04:06,120 --> 00:04:09,120
Speaker 3: I am Jorgem, a cartoonist and the creator of PhD comics.

84
00:04:09,280 --> 00:04:12,480
Speaker 1: Hi, I'm Daniel. I'm a particle physicist and a professor,

85
00:04:12,800 --> 00:04:14,760
Speaker 1: and I never seem to have enough time.

86
00:04:15,040 --> 00:04:17,760
Speaker 3: Really, can't you just make time in your particle collider?

87
00:04:18,160 --> 00:04:20,400
Speaker 3: I mean right, it's called space time. Can you just

88
00:04:20,440 --> 00:04:22,040
Speaker 3: transform from space into time?

89
00:04:22,920 --> 00:04:25,160
Speaker 1: Now, what I need to do is to speed up

90
00:04:25,200 --> 00:04:27,120
Speaker 1: the rest of the world near the speed of light.

91
00:04:27,200 --> 00:04:29,400
Speaker 1: So that it runs slowly, and then I can just

92
00:04:29,400 --> 00:04:31,800
Speaker 1: get all my work done while everybody else is frozen.

93
00:04:31,920 --> 00:04:34,159
Speaker 3: Whoh, that's a good idea. But then you'd be left behind.

94
00:04:34,200 --> 00:04:37,760
Speaker 3: Everyone would be really far away, you'd be light years away.

95
00:04:37,800 --> 00:04:38,960
Speaker 3: But you would catch up and work.

96
00:04:39,040 --> 00:04:39,440
Speaker 2: That's right.

97
00:04:39,920 --> 00:04:42,159
Speaker 1: I would made all my deadlines even though I'd be

98
00:04:42,279 --> 00:04:43,719
Speaker 1: in the neighboring star system.

99
00:04:43,800 --> 00:04:45,640
Speaker 3: Yeah, there you go. And then how do you turn

100
00:04:45,680 --> 00:04:46,800
Speaker 3: your work in? You can't.

101
00:04:49,120 --> 00:04:50,599
Speaker 1: I knew there was a flaw on this plan.

102
00:04:50,960 --> 00:04:53,360
Speaker 3: Yeah, you paradox yourself into unemployment.

103
00:04:54,440 --> 00:04:55,919
Speaker 1: The twin professor paradox.

104
00:04:56,200 --> 00:04:59,000
Speaker 3: But welcome to our podcast Daniel and Jorge Explain the Universe,

105
00:04:59,040 --> 00:05:00,640
Speaker 3: a production of I Radio.

106
00:05:00,560 --> 00:05:03,800
Speaker 1: In which we take that mental journey around the universe,

107
00:05:04,000 --> 00:05:06,960
Speaker 1: speeding your brain up to near the speed of light,

108
00:05:07,240 --> 00:05:09,960
Speaker 1: so that we can try to understand the very nature

109
00:05:10,040 --> 00:05:13,279
Speaker 1: of the universe that we find ourselves in, this incredible,

110
00:05:13,320 --> 00:05:17,080
Speaker 1: glittering cosmos, with all of its wonderful questions that it inspires,

111
00:05:17,200 --> 00:05:19,200
Speaker 1: the things that make us go, huh, why is it

112
00:05:19,320 --> 00:05:21,839
Speaker 1: like that? Why couldn't it be like this other thing?

113
00:05:22,080 --> 00:05:24,880
Speaker 1: We dig into all of that on this podcast. We

114
00:05:24,920 --> 00:05:27,520
Speaker 1: stare right into the abyss of our ignorance, and we

115
00:05:27,640 --> 00:05:30,440
Speaker 1: ask why, and we do our best to explain what

116
00:05:30,480 --> 00:05:32,080
Speaker 1: we do and don't know to you.

117
00:05:32,440 --> 00:05:35,240
Speaker 3: Yeah, because it is a pretty wonderful universe. But it's

118
00:05:35,279 --> 00:05:38,240
Speaker 3: also kind of a weird universe. We grow up thinking

119
00:05:38,279 --> 00:05:40,919
Speaker 3: that space is fixed and firm and never change it,

120
00:05:40,960 --> 00:05:44,360
Speaker 3: but actually it sort of does. It's a squishy eh

121
00:05:44,400 --> 00:05:45,680
Speaker 3: and also kind of ripley.

122
00:05:45,760 --> 00:05:48,000
Speaker 1: I'm glad it's a weird universe, though, What would it

123
00:05:48,040 --> 00:05:51,080
Speaker 1: be like if we were doing physics and discovering Yeah,

124
00:05:51,120 --> 00:05:53,800
Speaker 1: the universe is basically exactly as you thought it was

125
00:05:53,920 --> 00:05:55,039
Speaker 1: and kind of boring.

126
00:05:55,160 --> 00:05:58,480
Speaker 3: After all, you'd have to switch careers to just writing jokes.

127
00:06:01,080 --> 00:06:03,080
Speaker 1: I don't think I could have that as a career.

128
00:06:03,200 --> 00:06:05,600
Speaker 1: But I wonder sometimes about how, you know, we find

129
00:06:05,600 --> 00:06:09,080
Speaker 1: the universe beautiful, We find nature beautiful, and we also

130
00:06:09,160 --> 00:06:12,240
Speaker 1: find it mysterious and interesting, And I wonder if that's

131
00:06:12,279 --> 00:06:14,880
Speaker 1: an accident or a product of the way the human

132
00:06:14,960 --> 00:06:18,040
Speaker 1: mind works, that we just find beauty and mystery everywhere

133
00:06:18,080 --> 00:06:18,600
Speaker 1: around us.

134
00:06:18,839 --> 00:06:21,320
Speaker 3: Yeah, or even like the word weird, like why is

135
00:06:21,360 --> 00:06:24,400
Speaker 3: it weird to us? Right? Like what makes us the

136
00:06:24,600 --> 00:06:26,920
Speaker 3: overall judges of what is weird and what is not?

137
00:06:27,120 --> 00:06:30,159
Speaker 3: Like maybe the universe is offended by us calling it weird.

138
00:06:30,279 --> 00:06:32,600
Speaker 1: Yeah, and then the word weird itself is weird. When

139
00:06:32,640 --> 00:06:34,840
Speaker 1: you say it enough times, it sounds pretty weird. It's

140
00:06:34,839 --> 00:06:37,200
Speaker 1: got an E and I in it, like weird, weird, weird.

141
00:06:37,360 --> 00:06:38,520
Speaker 1: It's a pretty weird word.

142
00:06:38,720 --> 00:06:40,720
Speaker 3: Yeah. Yeah, but that's the English people's fault.

143
00:06:42,279 --> 00:06:43,320
Speaker 1: Blame it on the Brits.

144
00:06:43,440 --> 00:06:45,880
Speaker 3: So yeah, it is a pretty, let's say, interesting universe.

145
00:06:45,880 --> 00:06:47,800
Speaker 3: Do you think the universe would be offended if we

146
00:06:47,839 --> 00:06:48,920
Speaker 3: call it interesting?

147
00:06:49,360 --> 00:06:51,880
Speaker 1: Sort of like living in interesting times? No, I think

148
00:06:51,880 --> 00:06:53,560
Speaker 1: it's good. I think we are lucky. It's one of

149
00:06:53,600 --> 00:06:55,119
Speaker 1: the things that makes life worth living.

150
00:06:55,360 --> 00:06:55,520
Speaker 6: You know.

151
00:06:55,560 --> 00:06:58,120
Speaker 1: People sometimes ask me this question, like why should we

152
00:06:58,120 --> 00:07:01,000
Speaker 1: fund particle physics? What good it is it? And I

153
00:07:01,040 --> 00:07:03,599
Speaker 1: hear my colleagues making arguments like, well, you know, we

154
00:07:03,720 --> 00:07:06,640
Speaker 1: might have spinoff technologies or we invented the World Wide Web.

155
00:07:06,800 --> 00:07:09,320
Speaker 1: But for me, the true answer is that it explores

156
00:07:09,360 --> 00:07:12,320
Speaker 1: the universe. It explores the nature of the human existence,

157
00:07:12,400 --> 00:07:15,120
Speaker 1: sort of the same way like art does you ask

158
00:07:15,160 --> 00:07:17,240
Speaker 1: an artist like why should we pay for art? Why

159
00:07:17,280 --> 00:07:19,880
Speaker 1: should people write books? Well, it's you know, just part

160
00:07:19,880 --> 00:07:22,560
Speaker 1: of the joy of life is unraveling the mystery of

161
00:07:22,560 --> 00:07:25,680
Speaker 1: the universe we find ourselves in. That's it, and that's enough.

162
00:07:25,880 --> 00:07:27,280
Speaker 3: Well, I'm not sure you want to be in the

163
00:07:27,280 --> 00:07:29,480
Speaker 3: same position that the arts are in trying to get

164
00:07:29,520 --> 00:07:33,040
Speaker 3: funding using that argument, So I would stick with the

165
00:07:33,120 --> 00:07:36,640
Speaker 3: World Wide Web and useful technology right now. To be honest, I.

166
00:07:36,600 --> 00:07:38,680
Speaker 1: Think you just haven't asked big enough, Like why don't

167
00:07:38,720 --> 00:07:41,720
Speaker 1: you pitch your ten billion dollar cartoon to the government.

168
00:07:41,800 --> 00:07:43,800
Speaker 1: You know, the more you ask for, the more you get.

169
00:07:43,920 --> 00:07:47,000
Speaker 3: I'm not sure the time is right for that crazy idea.

170
00:07:46,920 --> 00:07:48,520
Speaker 1: The large hay drawing cartoon.

171
00:07:48,800 --> 00:07:50,840
Speaker 3: Yeah, there you go. It will break open the universe

172
00:07:50,880 --> 00:07:53,840
Speaker 3: probably and create imaginary black holes of ink that will

173
00:07:53,880 --> 00:07:54,680
Speaker 3: swallow up the earth.

174
00:07:54,840 --> 00:07:57,040
Speaker 1: That's right, that sounds good. I'd read that. I'd pitch

175
00:07:57,080 --> 00:07:59,280
Speaker 1: in my tax dollars for that. Anyway, we love the

176
00:07:59,400 --> 00:08:03,240
Speaker 1: universe is sies and that presents us with really fun, interesting,

177
00:08:03,360 --> 00:08:06,400
Speaker 1: basic questions, things that we don't understand about, you know,

178
00:08:06,680 --> 00:08:09,080
Speaker 1: the very like ABC's of reality.

179
00:08:09,280 --> 00:08:11,960
Speaker 3: Yeah, because I guess you know, we grow up experiencing

180
00:08:12,000 --> 00:08:14,240
Speaker 3: the universe in one way and we think it works

181
00:08:14,240 --> 00:08:16,080
Speaker 3: in this certain way in our brains. But really, when

182
00:08:16,080 --> 00:08:18,560
Speaker 3: you sort of drill down into it or you scale

183
00:08:18,680 --> 00:08:21,440
Speaker 3: up to bigger things. There are big surprises, and it

184
00:08:21,440 --> 00:08:22,880
Speaker 3: doesn't work the way we think it does.

185
00:08:23,000 --> 00:08:24,520
Speaker 1: Yeah, I think of the universe as sort of like

186
00:08:24,760 --> 00:08:26,960
Speaker 1: a ladder. You know, if you look at it at

187
00:08:27,000 --> 00:08:30,040
Speaker 1: one distance scale and one time scale, it works a

188
00:08:30,040 --> 00:08:32,839
Speaker 1: certain way. If you look at it another distance scale,

189
00:08:32,920 --> 00:08:35,280
Speaker 1: like if you're looking at particles or if you're looking

190
00:08:35,280 --> 00:08:38,920
Speaker 1: at water droplets or galaxies, there seem to be different

191
00:08:39,040 --> 00:08:42,880
Speaker 1: rules that apply at these different distance scales, and that's fascinating.

192
00:08:42,920 --> 00:08:45,240
Speaker 1: It makes you wonder, like, are any of these fundamental

193
00:08:45,240 --> 00:08:47,679
Speaker 1: Are we learning anything really deep and true about the

194
00:08:47,760 --> 00:08:50,040
Speaker 1: universe or does it all just depend on the questions

195
00:08:50,040 --> 00:08:50,520
Speaker 1: you're asking?

196
00:08:50,840 --> 00:08:53,120
Speaker 3: And so it's not just scientists who have questions about

197
00:08:53,160 --> 00:08:55,480
Speaker 3: the universe and about the nature of the universe. It's

198
00:08:55,520 --> 00:08:58,320
Speaker 3: also our listeners and everyday people just like you.

199
00:08:58,480 --> 00:09:02,520
Speaker 1: That's right, because remember that science is just people asking questions,

200
00:09:02,720 --> 00:09:06,000
Speaker 1: and the investigations we do are motivated by the individual

201
00:09:06,080 --> 00:09:09,920
Speaker 1: questions of individual scientists wondering things about the universe, and

202
00:09:10,000 --> 00:09:13,120
Speaker 1: that includes you, because we are all out there wondering

203
00:09:13,160 --> 00:09:15,560
Speaker 1: about the universe and trying to figure it out.

204
00:09:15,679 --> 00:09:18,000
Speaker 3: So today we are tackling a question that we got

205
00:09:18,040 --> 00:09:22,000
Speaker 3: from a listener who comes from Sweden. It's Henrik, and

206
00:09:22,120 --> 00:09:25,160
Speaker 3: Henrik is a pretty interesting question about time. So here

207
00:09:25,200 --> 00:09:26,000
Speaker 3: is Henrik's question.

208
00:09:26,160 --> 00:09:30,319
Speaker 7: Hi, Danielle Rogez. I'm Hendrik from Sweden and I have

209
00:09:30,480 --> 00:09:34,600
Speaker 7: been wondering if time could be pixelated? Is there any

210
00:09:34,640 --> 00:09:38,720
Speaker 7: minimum unit of time? Or could it be infinitely short?

211
00:09:39,240 --> 00:09:42,160
Speaker 7: And when I listen to your episode about space being

212
00:09:42,200 --> 00:09:46,000
Speaker 7: pixelated or not, I started wondering if time could be

213
00:09:46,040 --> 00:09:51,160
Speaker 7: pixelated while space isn't, or vice versa. Thank you guys.

214
00:09:51,280 --> 00:09:53,400
Speaker 3: All right, it's a pretty interesting question from Henrik. So

215
00:09:53,520 --> 00:10:02,280
Speaker 3: today on the podcast will be tackling is time pixelated?

216
00:10:02,760 --> 00:10:06,400
Speaker 3: That's a pretty strange question. Is time pixelated? I don't

217
00:10:06,480 --> 00:10:08,640
Speaker 3: usually associate pixels with time.

218
00:10:08,800 --> 00:10:12,520
Speaker 1: Yeah, it's a wonderful question, and I love hearing Henrik

219
00:10:12,679 --> 00:10:15,120
Speaker 1: do physics. You know, he is absorbing what we were

220
00:10:15,160 --> 00:10:18,240
Speaker 1: talking about and he's taking it to the next natural consequence.

221
00:10:18,520 --> 00:10:19,959
Speaker 1: And that's what you got to do with the theory.

222
00:10:19,960 --> 00:10:22,360
Speaker 1: You say, all right, well, this describes what I'm thinking

223
00:10:22,400 --> 00:10:25,559
Speaker 1: about or describes what I've seen. Can I extrapolate from

224
00:10:25,600 --> 00:10:27,520
Speaker 1: it to the rest of the universe or one of

225
00:10:27,559 --> 00:10:30,559
Speaker 1: the consequences of it? How can I test and explore this.

226
00:10:30,760 --> 00:10:33,640
Speaker 1: So that's exactly doing physics. So kudos to you, Henrich,

227
00:10:33,760 --> 00:10:35,520
Speaker 1: for doing some physics in your mind.

228
00:10:35,679 --> 00:10:37,400
Speaker 3: Yeah, Daniel will be sending you a check in the

229
00:10:37,400 --> 00:10:40,480
Speaker 3: mill right now. Right after this podcast.

230
00:10:40,360 --> 00:10:42,880
Speaker 1: I'm going to email you some Swedish fish, my favorite

231
00:10:42,880 --> 00:10:43,559
Speaker 1: Swedish candy.

232
00:10:43,600 --> 00:10:45,559
Speaker 3: All right. So then it's a pretty interesting question. And

233
00:10:45,640 --> 00:10:47,960
Speaker 3: Henrik was saying that he listened to an episode that

234
00:10:48,000 --> 00:10:50,720
Speaker 3: we had about whether or not space is pixelated. So

235
00:10:50,760 --> 00:10:54,200
Speaker 3: there's this idea that space could be pixelated, meaning like

236
00:10:54,320 --> 00:10:57,120
Speaker 3: it's not smooth and continuous, maybe it's like a grid

237
00:10:57,240 --> 00:11:00,960
Speaker 3: or something, or it's discreet at the very small as level.

238
00:11:01,120 --> 00:11:03,679
Speaker 3: And his question is whether or not it applies to

239
00:11:03,800 --> 00:11:04,400
Speaker 3: time as well.

240
00:11:04,520 --> 00:11:06,640
Speaker 1: That's right, because we often talk on the podcast about

241
00:11:06,679 --> 00:11:10,200
Speaker 1: how space and time are related and that in relativity

242
00:11:10,240 --> 00:11:13,520
Speaker 1: at least we see them as parts of space time

243
00:11:13,679 --> 00:11:17,000
Speaker 1: a four dimensional object. So it's a very natural question.

244
00:11:17,240 --> 00:11:19,200
Speaker 3: Yeah, and so what did we conclude in that podcast

245
00:11:19,200 --> 00:11:20,839
Speaker 3: episode about space being pixelated?

246
00:11:20,880 --> 00:11:23,840
Speaker 1: We concluded that we don't know, and we might never know,

247
00:11:24,280 --> 00:11:27,000
Speaker 1: but there are good reasons to think that space might

248
00:11:27,040 --> 00:11:28,520
Speaker 1: be pixelated.

249
00:11:28,160 --> 00:11:30,920
Speaker 3: Right, due to like quantum physics, and they're being like

250
00:11:30,960 --> 00:11:33,680
Speaker 3: a theoretical plank scale to the universe as well.

251
00:11:33,760 --> 00:11:36,839
Speaker 1: Right, exactly, we don't know how small the pixels of

252
00:11:36,880 --> 00:11:39,560
Speaker 1: space are if they exist, and we have a very simple,

253
00:11:39,679 --> 00:11:42,120
Speaker 1: kind of bad estimate for how small they might be,

254
00:11:42,559 --> 00:11:45,880
Speaker 1: just by multiplying constants of the universe together. And it's

255
00:11:46,000 --> 00:11:49,280
Speaker 1: very very small number, like ten to the minus thirty

256
00:11:49,400 --> 00:11:52,439
Speaker 1: five meters. That's not a measurement of how small the

257
00:11:52,480 --> 00:11:55,640
Speaker 1: space pixels are or proof that space pixels exist. But

258
00:11:55,679 --> 00:11:58,720
Speaker 1: if you have no other information about how to estimate it,

259
00:11:58,840 --> 00:12:00,680
Speaker 1: this is all you can do. Gives you a sense

260
00:12:00,679 --> 00:12:03,319
Speaker 1: for like what the neighborhood of the size might be.

261
00:12:03,400 --> 00:12:05,199
Speaker 3: All right, So then if you're curious, you can look

262
00:12:05,280 --> 00:12:08,520
Speaker 3: up that episode in our archive. But today we're talking

263
00:12:08,559 --> 00:12:11,320
Speaker 3: about time and whether it's pixelated, and so, as usually

264
00:12:11,320 --> 00:12:13,240
Speaker 3: we'll be were wondering how many people out there had

265
00:12:13,240 --> 00:12:15,520
Speaker 3: thought about this question or had had time to think

266
00:12:15,520 --> 00:12:18,720
Speaker 3: about this question at least a pixel of time, and

267
00:12:18,880 --> 00:12:20,839
Speaker 3: maybe had an answer for it. So Daniel went out

268
00:12:20,840 --> 00:12:24,920
Speaker 3: there into the internet to ask listeners is time pixelated?

269
00:12:25,040 --> 00:12:28,199
Speaker 1: And so if you have time to donate your thoughts

270
00:12:28,240 --> 00:12:32,160
Speaker 1: on random physics questions for future podcast episodes, please don't

271
00:12:32,200 --> 00:12:35,920
Speaker 1: be shy. Write to me too. Questions at Danielandjorge dot com.

272
00:12:35,960 --> 00:12:37,440
Speaker 3: So think about it for a second. Do you think

273
00:12:37,480 --> 00:12:40,720
Speaker 3: there is a minimum amount of time in the universe?

274
00:12:41,280 --> 00:12:42,360
Speaker 3: Here's what people have to say.

275
00:12:42,559 --> 00:12:46,560
Speaker 8: I guess if you zoomed in far enough, time might

276
00:12:46,600 --> 00:12:50,680
Speaker 8: be pixelated, like if you imagined it as a film strip,

277
00:12:50,760 --> 00:12:55,199
Speaker 8: if you zoomed in just millions and millions and millions

278
00:12:55,240 --> 00:13:00,720
Speaker 8: of times, that it would be moving sort of in frames,

279
00:13:00,760 --> 00:13:02,640
Speaker 8: as if like a movie kind of thing.

280
00:13:03,640 --> 00:13:05,360
Speaker 6: Tom, pixelation, haven't heard of it?

281
00:13:07,000 --> 00:13:07,760
Speaker 7: Tell me about it?

282
00:13:07,760 --> 00:13:15,280
Speaker 6: Sounds crazy, that is, it's a usual thing. So do

283
00:13:15,280 --> 00:13:17,319
Speaker 6: you think it's pixelated or continuous?

284
00:13:18,720 --> 00:13:20,560
Speaker 9: Okay, I'm.

285
00:13:21,960 --> 00:13:23,760
Speaker 6: Continuous, It's continuous.

286
00:13:23,800 --> 00:13:24,120
Speaker 9: Okay.

287
00:13:24,920 --> 00:13:26,880
Speaker 2: Wow, man, I don't even know how to wrap my

288
00:13:26,920 --> 00:13:27,880
Speaker 2: head around this question.

289
00:13:28,000 --> 00:13:29,199
Speaker 6: Is time pixelated?

290
00:13:29,760 --> 00:13:30,800
Speaker 7: What does that even mean?

291
00:13:31,559 --> 00:13:34,000
Speaker 9: Is it just like if a second is a pixel

292
00:13:34,120 --> 00:13:35,680
Speaker 9: or even nanosecond is a pixel?

293
00:13:36,400 --> 00:13:39,120
Speaker 7: I have no idea how to answer this question. I

294
00:13:39,200 --> 00:13:41,080
Speaker 7: really don't know what that question means.

295
00:13:42,120 --> 00:13:48,400
Speaker 1: Maybe like is time quantized in some form? Honest, I

296
00:13:48,480 --> 00:13:52,960
Speaker 1: have no idea. Time is very strange that we don't know.

297
00:13:53,720 --> 00:13:54,480
Speaker 2: I'm not sure.

298
00:13:55,000 --> 00:13:58,080
Speaker 3: I think that there are some theories that suggest it

299
00:13:58,160 --> 00:14:01,480
Speaker 3: might be, but I don't know that we've measured that definitively.

300
00:14:02,160 --> 00:14:04,720
Speaker 9: My understanding of the measuring of time is that it's

301
00:14:04,760 --> 00:14:12,960
Speaker 9: not infinitely divisible, that it is hypothesized that ultimately you'll

302
00:14:13,000 --> 00:14:15,560
Speaker 9: get to units of time that are so short you

303
00:14:15,600 --> 00:14:19,080
Speaker 9: can't get any short. And I think it's referred to

304
00:14:19,120 --> 00:14:20,120
Speaker 9: as plunk.

305
00:14:19,840 --> 00:14:29,760
Speaker 10: Time pixilated like all the video games. I'm not sure about.

306
00:14:29,800 --> 00:14:33,120
Speaker 10: The term doesn't seem right.

307
00:14:33,240 --> 00:14:34,000
Speaker 1: I probably not.

308
00:14:34,840 --> 00:14:38,920
Speaker 11: I have no idea from a physics standpoint, but from

309
00:14:39,000 --> 00:14:44,440
Speaker 11: a perception standpoint, I feel like it is, and I

310
00:14:44,480 --> 00:14:47,760
Speaker 11: think deja vous has something to do with that. It's

311
00:14:47,840 --> 00:14:52,600
Speaker 11: like it arrives into my brain in little packets and

312
00:14:52,640 --> 00:14:56,280
Speaker 11: then my brain goes and smooths it all out after

313
00:14:56,320 --> 00:15:00,000
Speaker 11: the fact, so that it in my memories it seems

314
00:15:00,280 --> 00:15:03,720
Speaker 11: like it's all smooth, and I can't actually sense what's

315
00:15:03,760 --> 00:15:04,840
Speaker 11: going on in real time.

316
00:15:05,680 --> 00:15:07,600
Speaker 6: I have no idea what that means.

317
00:15:08,280 --> 00:15:13,640
Speaker 11: I guess not because I think it's continuous with the

318
00:15:13,680 --> 00:15:16,160
Speaker 11: way that Madam moves in space.

319
00:15:16,960 --> 00:15:20,320
Speaker 3: All right. Not a lot of ideas here. Maybe people

320
00:15:20,320 --> 00:15:22,000
Speaker 3: didn't spend enough time thinking about it.

321
00:15:22,040 --> 00:15:24,640
Speaker 1: They only thought one or two units of time on this,

322
00:15:24,720 --> 00:15:26,280
Speaker 1: and they should have at least spent ten or.

323
00:15:26,240 --> 00:15:28,680
Speaker 3: Well, yeah, it's a tough question. It seems to have

324
00:15:28,680 --> 00:15:31,120
Speaker 3: puzzled people. Most people just threw their hands up in

325
00:15:31,160 --> 00:15:32,080
Speaker 3: the air and said, I don't know.

326
00:15:32,360 --> 00:15:32,560
Speaker 7: Yeah.

327
00:15:32,600 --> 00:15:35,360
Speaker 1: It seems a little bit more foreign to people than

328
00:15:35,400 --> 00:15:38,640
Speaker 1: the idea that space is pixelated, Like you're familiar with

329
00:15:38,720 --> 00:15:42,600
Speaker 1: looking at a screen, the idea of locations being a grid.

330
00:15:42,920 --> 00:15:46,200
Speaker 1: That makes some sense. But the idea of time being pixelated,

331
00:15:46,520 --> 00:15:49,400
Speaker 1: that you know that there are discrete units of time

332
00:15:49,520 --> 00:15:52,440
Speaker 1: as we move forward, that were stepping forward instead of

333
00:15:52,480 --> 00:15:55,480
Speaker 1: sliding forward, that seems to be a little bit more alien.

334
00:15:55,720 --> 00:15:59,400
Speaker 3: Yeah, so let's maybe tackle this one kind of idea

335
00:15:59,400 --> 00:16:01,120
Speaker 3: of the time. So, first of all, what would it

336
00:16:01,200 --> 00:16:03,760
Speaker 3: mean for time to be pixelated? Would it mean like

337
00:16:03,800 --> 00:16:06,120
Speaker 3: you can cut up time or you can step through

338
00:16:06,160 --> 00:16:09,120
Speaker 3: time in small increments, but at some point there comes

339
00:16:09,120 --> 00:16:12,520
Speaker 3: a point where you can take smaller steps in time.

340
00:16:12,720 --> 00:16:16,040
Speaker 1: Mm hmm. There's sort of two very different but closely

341
00:16:16,120 --> 00:16:19,520
Speaker 1: related ways for time to be discrete, for there to

342
00:16:19,520 --> 00:16:23,000
Speaker 1: be like a minimal, sensible unit of time. The first

343
00:16:23,040 --> 00:16:26,280
Speaker 1: is what you were just talking about. This idea of pixelization,

344
00:16:26,360 --> 00:16:29,320
Speaker 1: and pixelization is something we think about for space, right,

345
00:16:29,360 --> 00:16:32,680
Speaker 1: like pixels on the screen. You can either be at

346
00:16:32,840 --> 00:16:35,600
Speaker 1: X equals seven or x equals eight, but you can't

347
00:16:35,600 --> 00:16:38,200
Speaker 1: be at x equals seven and a half. So that's

348
00:16:38,320 --> 00:16:42,160
Speaker 1: very natural sense for space and for time. The idea

349
00:16:42,200 --> 00:16:45,880
Speaker 1: would be that things step forwards in time that you

350
00:16:45,920 --> 00:16:48,680
Speaker 1: could be at like time equals one point seven or

351
00:16:48,680 --> 00:16:51,360
Speaker 1: time equals one point eight, but there is no time

352
00:16:51,400 --> 00:16:54,160
Speaker 1: equals one point seven and a half. That the universe

353
00:16:54,240 --> 00:16:57,360
Speaker 1: just goes from one point seven boom to one point eight.

354
00:16:57,480 --> 00:16:59,840
Speaker 1: It's like ticks on a clock, but there's no moment

355
00:17:00,080 --> 00:17:01,400
Speaker 1: in between the tics.

356
00:17:01,200 --> 00:17:03,360
Speaker 3: Like you can't have a half of a second or

357
00:17:03,400 --> 00:17:04,000
Speaker 3: something like that.

358
00:17:04,119 --> 00:17:07,280
Speaker 1: Yeah, and you know, obviously seconds aren't the minimum unit

359
00:17:07,400 --> 00:17:09,520
Speaker 1: of time. You can have half of a second if

360
00:17:09,560 --> 00:17:12,720
Speaker 1: time units exist, but there's a minimum discrete chunk of time,

361
00:17:12,760 --> 00:17:15,240
Speaker 1: it would be super duper small. So that to us

362
00:17:15,280 --> 00:17:17,160
Speaker 1: it seems continuous.

363
00:17:16,840 --> 00:17:19,240
Speaker 3: Right, and you think it doesn't exist or like what

364
00:17:19,359 --> 00:17:21,439
Speaker 3: happens in between those two times?

365
00:17:21,800 --> 00:17:24,719
Speaker 1: Yeah, well what does it mean for the universe to

366
00:17:24,720 --> 00:17:28,040
Speaker 1: be in between those times? It's like it doesn't have

367
00:17:28,240 --> 00:17:31,359
Speaker 1: a meaning, Like time is here and time is there,

368
00:17:31,600 --> 00:17:34,480
Speaker 1: but in between there isn't anything. It just doesn't exist.

369
00:17:34,480 --> 00:17:36,800
Speaker 1: This is something that's sort of familiar to us from

370
00:17:36,920 --> 00:17:41,160
Speaker 1: learning quantum mechanics, that not everything has like a smooth

371
00:17:41,320 --> 00:17:44,040
Speaker 1: classical path, you know, like an electron. You measure it

372
00:17:44,080 --> 00:17:46,720
Speaker 1: here and then you later you measure it over there.

373
00:17:47,119 --> 00:17:50,199
Speaker 1: Does that mean that it went from here to there? No,

374
00:17:50,280 --> 00:17:52,800
Speaker 1: it just means it was here and then it was there.

375
00:17:52,840 --> 00:17:56,600
Speaker 1: It doesn't have to have a location in between. We

376
00:17:56,720 --> 00:17:59,399
Speaker 1: think of everything as smooth and continuous because that's the

377
00:17:59,400 --> 00:18:02,000
Speaker 1: way it seems to us, because we're kind of big

378
00:18:02,080 --> 00:18:05,000
Speaker 1: and slow. But the universe, as you were saying earlier,

379
00:18:05,160 --> 00:18:08,280
Speaker 1: could be drastically different from the way we experience it, all.

380
00:18:08,280 --> 00:18:11,360
Speaker 3: Right, So that's one possibility that time just doesn't exist

381
00:18:11,440 --> 00:18:14,720
Speaker 3: in between time pixels, like there's a grid of the

382
00:18:14,960 --> 00:18:16,000
Speaker 3: time in the universe.

383
00:18:16,040 --> 00:18:18,400
Speaker 1: And that's actually something that makes sense to us sort

384
00:18:18,400 --> 00:18:22,240
Speaker 1: of numerically, like when we simulate things in the computer.

385
00:18:22,480 --> 00:18:25,040
Speaker 1: You want to describe, for example, how a hurricane moves

386
00:18:25,200 --> 00:18:27,880
Speaker 1: or how galaxies form, and we want to simulate them.

387
00:18:27,960 --> 00:18:30,159
Speaker 1: That's exactly how we do it. We make a grid

388
00:18:30,280 --> 00:18:34,000
Speaker 1: in time, and we step our simulated universe forward. We say,

389
00:18:34,040 --> 00:18:36,440
Speaker 1: something's happening right now, what's going to happen at the

390
00:18:36,480 --> 00:18:38,480
Speaker 1: next time step, and you can decide is it going

391
00:18:38,560 --> 00:18:40,840
Speaker 1: to be a nanosecond in the future or ten minutes

392
00:18:40,840 --> 00:18:43,640
Speaker 1: in the future, depends on how much computing time you have.

393
00:18:43,920 --> 00:18:46,240
Speaker 1: But it's very natural to step things forward in time

394
00:18:46,480 --> 00:18:48,120
Speaker 1: in simulations.

395
00:18:47,600 --> 00:18:50,680
Speaker 3: Right, You use simulations with time steps. But simulations are

396
00:18:50,680 --> 00:18:53,000
Speaker 3: not perfect, right, And that's one of the main reasons

397
00:18:53,040 --> 00:18:55,199
Speaker 3: is that they do have sort of a resolution. It

398
00:18:55,240 --> 00:18:57,960
Speaker 3: doesn't do it continuously like the universe sort of seems

399
00:18:58,000 --> 00:18:58,159
Speaker 3: to be.

400
00:18:58,320 --> 00:19:01,240
Speaker 1: Yeah, exactly, they're not continuous, discret and you're right that

401
00:19:01,320 --> 00:19:04,560
Speaker 1: you want really small time steps so that you're extrapolating

402
00:19:04,680 --> 00:19:07,159
Speaker 1: in a reasonable way. But it might be that the

403
00:19:07,240 --> 00:19:09,679
Speaker 1: universe actually does have the same sort of time steps,

404
00:19:09,680 --> 00:19:11,920
Speaker 1: and if you did your simulation with a time step

405
00:19:12,040 --> 00:19:15,120
Speaker 1: equal to that of the universe, then it would be perfect.

406
00:19:16,040 --> 00:19:17,960
Speaker 3: Wow, that would be weird, right, Like the universe would

407
00:19:17,960 --> 00:19:21,320
Speaker 3: be operating at the minimum possible time step because but

408
00:19:21,359 --> 00:19:25,080
Speaker 3: the computer is in the universe, So that would blows

409
00:19:25,080 --> 00:19:26,920
Speaker 3: my mind a little bit. But all right, So that's

410
00:19:26,920 --> 00:19:29,920
Speaker 3: the first kind of time pixelization. What's the second.

411
00:19:30,080 --> 00:19:33,840
Speaker 1: The second is that time isn't actually pixelized in the

412
00:19:33,880 --> 00:19:36,960
Speaker 1: sense that you could have any value of time. It's

413
00:19:36,960 --> 00:19:39,880
Speaker 1: not like values in between one point seven and one

414
00:19:39,880 --> 00:19:42,439
Speaker 1: point eight are disallowed. If you try to measure like

415
00:19:42,520 --> 00:19:45,600
Speaker 1: when did something happen, you could get any number between

416
00:19:45,600 --> 00:19:48,040
Speaker 1: one point seven and one point eight. All those values

417
00:19:48,080 --> 00:19:52,000
Speaker 1: are real and possible. In this idea, though, there's a

418
00:19:52,040 --> 00:19:55,679
Speaker 1: minimum resolution, like you can't measure differences in time that

419
00:19:55,720 --> 00:19:58,199
Speaker 1: are smaller than a certain number, Like if you measure

420
00:19:58,240 --> 00:20:01,240
Speaker 1: something twice, you can't get two menasurements that are closer

421
00:20:01,280 --> 00:20:04,919
Speaker 1: than a certain minimum distance, but you can get any value.

422
00:20:04,960 --> 00:20:07,560
Speaker 1: So it's sort of like you have this minimum resolution,

423
00:20:07,640 --> 00:20:10,399
Speaker 1: but it can slide up and down the timescale and

424
00:20:10,480 --> 00:20:11,119
Speaker 1: land wherever.

425
00:20:11,760 --> 00:20:13,240
Speaker 3: Okay, I think I know what you're saying. You're saying

426
00:20:13,240 --> 00:20:17,280
Speaker 3: that maybe like every possible timestep exists or is possible,

427
00:20:17,359 --> 00:20:20,119
Speaker 3: Like you can have one point oh three seconds and

428
00:20:20,400 --> 00:20:25,520
Speaker 3: one point two four seven seconds, but maybe at some point,

429
00:20:25,680 --> 00:20:28,960
Speaker 3: at some scale of smallness and time, it just kind

430
00:20:29,000 --> 00:20:32,119
Speaker 3: of becomes random or fuzzy or sort of unknowable.

431
00:20:32,240 --> 00:20:35,080
Speaker 1: Yeah, exactly, And we can think about that because we

432
00:20:35,119 --> 00:20:38,199
Speaker 1: think about quantum particles in exactly that way. Like an

433
00:20:38,240 --> 00:20:42,679
Speaker 1: electron is quantized, right, it's a single object quantized of

434
00:20:42,720 --> 00:20:46,600
Speaker 1: the electron field. So it's got a certain like natural

435
00:20:46,640 --> 00:20:49,320
Speaker 1: width to it, below which you can't really probe where

436
00:20:49,359 --> 00:20:53,160
Speaker 1: its location is, but it could be anywhere. It can

437
00:20:53,240 --> 00:20:56,959
Speaker 1: live in continuous space. If space is continuous, you can

438
00:20:57,000 --> 00:21:00,360
Speaker 1: still have discrete objects inside of it. And that's same way.

439
00:21:00,400 --> 00:21:03,720
Speaker 1: Time might be like fundamentally continuous, but there might be

440
00:21:03,760 --> 00:21:07,160
Speaker 1: a minimum basic resolution of time below which the time

441
00:21:07,200 --> 00:21:08,879
Speaker 1: difference between two events has.

442
00:21:08,800 --> 00:21:11,960
Speaker 3: No meaning, no meaning. But it exists. But it's sort

443
00:21:11,960 --> 00:21:14,800
Speaker 3: of random. And because it's random, you're saying it doesn't

444
00:21:14,800 --> 00:21:16,919
Speaker 3: have any meaning. But is that really pixelated?

445
00:21:16,920 --> 00:21:17,120
Speaker 1: Though?

446
00:21:17,240 --> 00:21:20,960
Speaker 3: Like it's it it doesn't fit our idea of a pixel, right,

447
00:21:21,000 --> 00:21:22,720
Speaker 3: It's more like there is no pixel, but it's sort

448
00:21:22,720 --> 00:21:23,879
Speaker 3: of fuzzy at a certain scale.

449
00:21:24,040 --> 00:21:26,359
Speaker 1: Yeah, exactly. It sets a scale which I think to

450
00:21:26,480 --> 00:21:29,960
Speaker 1: the physicist is interesting because it means you can't infinitely

451
00:21:30,000 --> 00:21:30,760
Speaker 1: divide time.

452
00:21:31,160 --> 00:21:31,320
Speaker 7: Right.

453
00:21:31,320 --> 00:21:33,280
Speaker 1: That was the other part of Hendrick's question, like can

454
00:21:33,359 --> 00:21:36,840
Speaker 1: you have infinitely small slices in time? Does it make

455
00:21:36,920 --> 00:21:39,720
Speaker 1: sense to think about things happening at one moment and

456
00:21:39,760 --> 00:21:43,600
Speaker 1: then ten to the minus one thousand seconds later, Like

457
00:21:43,640 --> 00:21:47,160
Speaker 1: does the universe really evolve things step by step at

458
00:21:47,160 --> 00:21:50,080
Speaker 1: that granularity? And what this would tell you is not

459
00:21:50,440 --> 00:21:53,240
Speaker 1: that things are locked into specific numbers, but that it

460
00:21:53,320 --> 00:21:55,760
Speaker 1: makes no sense to think about steps in time that

461
00:21:55,920 --> 00:21:56,879
Speaker 1: are that small.

462
00:21:57,480 --> 00:21:58,520
Speaker 3: You can just make stuff us.

463
00:21:59,560 --> 00:22:03,480
Speaker 1: It's known and it's undetermined, right in the same way

464
00:22:03,480 --> 00:22:07,240
Speaker 1: that like not all the information about an electron is knowable,

465
00:22:07,600 --> 00:22:09,880
Speaker 1: not just because we can't measure it, but because it's

466
00:22:09,920 --> 00:22:13,760
Speaker 1: not specified, is undetermined. In that same way, pieces of

467
00:22:13,800 --> 00:22:16,879
Speaker 1: time smaller than like whatever is the minimum resolution and

468
00:22:16,960 --> 00:22:19,360
Speaker 1: time are not known or knowable.

469
00:22:19,480 --> 00:22:21,000
Speaker 3: All right, Well, those are the two ways in which

470
00:22:21,040 --> 00:22:24,480
Speaker 3: time could be pixelated, And so let's get into why

471
00:22:24,520 --> 00:22:26,720
Speaker 3: we think it might be pixelated and whether or not

472
00:22:26,840 --> 00:22:29,480
Speaker 3: we'll ever know if it is or not. But first,

473
00:22:29,520 --> 00:22:30,719
Speaker 3: let's take a quick break.

474
00:22:34,880 --> 00:22:37,880
Speaker 1: With big wireless providers, what you see is never what

475
00:22:37,920 --> 00:22:40,600
Speaker 1: you get. Somewhere between the store and your first month's bill,

476
00:22:40,640 --> 00:22:43,720
Speaker 1: the price you thought you were paying magically skyrockets. With

477
00:22:43,840 --> 00:22:47,280
Speaker 1: mint Mobile, you'll never have to worry about Gotcha's ever again.

478
00:22:47,320 --> 00:22:49,560
Speaker 1: When mint Mobile says fifteen dollars a month for a

479
00:22:49,600 --> 00:22:52,400
Speaker 1: three month plan, they really mean it. I've used mint

480
00:22:52,400 --> 00:22:54,879
Speaker 1: Mobile and the call quality is always so crisp and

481
00:22:54,960 --> 00:22:57,400
Speaker 1: so clear. I can recommend it to you, so say

482
00:22:57,440 --> 00:23:00,679
Speaker 1: Bye bye to your overpriced wireless plans, jaw dropping monthly

483
00:23:00,720 --> 00:23:03,800
Speaker 1: bills and unexpected overages. You can use your own phone

484
00:23:03,880 --> 00:23:06,359
Speaker 1: with any mint Mobile plan and bring your phone number

485
00:23:06,520 --> 00:23:09,800
Speaker 1: along with your existing contacts. So dig your overpriced wireless

486
00:23:09,800 --> 00:23:12,200
Speaker 1: with mint Mobiles deal and get three months a premium

487
00:23:12,240 --> 00:23:14,679
Speaker 1: wireless service for fifteen bucks a month. To get this

488
00:23:14,720 --> 00:23:17,160
Speaker 1: new customer offer and your new three month premium wireless

489
00:23:17,160 --> 00:23:19,160
Speaker 1: plan for just fifteen bucks a month, go to mintmobile

490
00:23:19,200 --> 00:23:22,679
Speaker 1: dot com slash universe. That's mintmobile dot com slash universe.

491
00:23:22,720 --> 00:23:24,679
Speaker 1: Cut your wireless bill to fifteen bucks a month. At

492
00:23:24,720 --> 00:23:27,840
Speaker 1: mintmobile dot com slash universe, forty five dollars upfront payment

493
00:23:27,840 --> 00:23:30,560
Speaker 1: required equivalent to fifteen dollars per month new customers on

494
00:23:30,640 --> 00:23:33,480
Speaker 1: first three month plan only speeds slower about forty gigabytes

495
00:23:33,480 --> 00:23:36,240
Speaker 1: On unlimited plan. Additional taxi spees and restrictions apply. See

496
00:23:36,280 --> 00:23:37,480
Speaker 1: mint mobile for details.

497
00:23:37,640 --> 00:23:40,680
Speaker 12: AI might be the most important new computer technology ever.

498
00:23:40,920 --> 00:23:44,159
Speaker 12: It's storming every industry and literally billions of dollars are

499
00:23:44,160 --> 00:23:48,399
Speaker 12: being invested, so buckle up. The problem is that AI

500
00:23:48,520 --> 00:23:51,320
Speaker 12: needs a lot of speed and processing power, So how

501
00:23:51,359 --> 00:23:54,520
Speaker 12: do you compete without cost spiraling out of control? It's

502
00:23:54,560 --> 00:23:56,880
Speaker 12: time to upgrade to the next generation of the cloud.

503
00:23:57,200 --> 00:24:02,360
Speaker 12: Oracle Cloud Infrastructure or OCI. OCI is a single platform

504
00:24:02,400 --> 00:24:07,280
Speaker 12: for your infrastructure, database, application development, and AI needs. OCI

505
00:24:07,440 --> 00:24:09,800
Speaker 12: has four to eight times the bandwidth of other clouds,

506
00:24:10,160 --> 00:24:13,720
Speaker 12: offers one consistent price instead of variable regional pricing, and

507
00:24:13,800 --> 00:24:16,920
Speaker 12: of course nobody does data better than Oracle. So now

508
00:24:16,960 --> 00:24:19,159
Speaker 12: you can train your AI models at twice the speed

509
00:24:19,359 --> 00:24:21,679
Speaker 12: and less than half the cost of other clouds. If

510
00:24:21,720 --> 00:24:23,920
Speaker 12: you want to do more and spend less, like Uber

511
00:24:24,080 --> 00:24:26,720
Speaker 12: eight by eight and Data Bricks Mosaic, take a free

512
00:24:26,720 --> 00:24:30,639
Speaker 12: test drive of OCI at Oracle dot com slash Strategic.

513
00:24:30,960 --> 00:24:36,200
Speaker 12: That's Oracle dot com slash Strategic Oracle dot com slash Strategic.

514
00:24:36,480 --> 00:24:39,399
Speaker 1: If you love iPhone, you'll love Apple Card. It's the

515
00:24:39,480 --> 00:24:43,320
Speaker 1: credit card designed for iPhone. It gives you unlimited daily

516
00:24:43,440 --> 00:24:46,399
Speaker 1: cash back that can earn four point four zero percent

517
00:24:46,560 --> 00:24:49,359
Speaker 1: annual percentage yield. When you open a high Yield Savings

518
00:24:49,400 --> 00:24:52,960
Speaker 1: account through Applecard, apply for Applecard in the wallet app,

519
00:24:53,080 --> 00:24:56,200
Speaker 1: subject to credit approval. Savings is available to Apple Card

520
00:24:56,240 --> 00:24:59,560
Speaker 1: owners subject to eligibility. Apple Card and Savings by Goldman

521
00:24:59,600 --> 00:25:02,520
Speaker 1: sax BA, Thank USA, Salt Lake City Branch member FDIC

522
00:25:02,920 --> 00:25:05,680
Speaker 1: terms and more at applecar dot com. When you pop

523
00:25:05,720 --> 00:25:07,600
Speaker 1: a piece of cheese into your mouth or enjoy a

524
00:25:07,680 --> 00:25:11,040
Speaker 1: rich spoonful of Greek yogurt, you're probably not thinking about

525
00:25:11,080 --> 00:25:14,480
Speaker 1: the environmental impact of each and every bite, But the

526
00:25:14,520 --> 00:25:17,359
Speaker 1: people in the dairy industry are. US Dairy has set

527
00:25:17,359 --> 00:25:21,959
Speaker 1: themselves some ambitious sustainability goals, including being greenhouse gas neutral

528
00:25:22,000 --> 00:25:24,400
Speaker 1: by twenty to fifty That's why they're working hard every

529
00:25:24,480 --> 00:25:27,560
Speaker 1: day to find new ways to reduce waste, conserve natural resources,

530
00:25:27,600 --> 00:25:31,120
Speaker 1: and drive down greenhouse gas emissions. Take water, for example,

531
00:25:31,200 --> 00:25:34,280
Speaker 1: most dairy farms reuse water up to four times the

532
00:25:34,320 --> 00:25:37,560
Speaker 1: same water cools the milk, cleans equipment, washes the barn,

533
00:25:37,680 --> 00:25:41,320
Speaker 1: and irrigates the crops. How is US dairy tackling greenhouse gases?

534
00:25:41,400 --> 00:25:44,440
Speaker 1: Many farms use anaerobic digestors that turn the methane from

535
00:25:44,400 --> 00:25:47,840
Speaker 1: maneuver into renewable energy that can power farms, towns, and

536
00:25:47,880 --> 00:25:50,120
Speaker 1: electric cars. So the next time you grab a slice

537
00:25:50,119 --> 00:25:52,000
Speaker 1: of pizza or lick an ice cream cone, know that

538
00:25:52,080 --> 00:25:54,720
Speaker 1: dairy farmers and processors around the country are using the

539
00:25:54,840 --> 00:25:58,560
Speaker 1: latest practices and innovations to provide the nutrient dense dairy

540
00:25:58,600 --> 00:26:01,280
Speaker 1: products we love with less of an impact. Visit us

541
00:26:01,359 --> 00:26:03,880
Speaker 1: dairy dot com slash sustainability to learn more.

542
00:26:12,320 --> 00:26:16,560
Speaker 3: All right, we're asking the question is time pixelated? And

543
00:26:16,640 --> 00:26:19,520
Speaker 3: so we had a whole episode about whether space was pixelated,

544
00:26:19,640 --> 00:26:22,000
Speaker 3: and we had all those reasons there. But now we're

545
00:26:22,040 --> 00:26:25,159
Speaker 3: asking if time is pixelated, And so the question is

546
00:26:25,200 --> 00:26:27,639
Speaker 3: why do we think time might be pixelated? It seems

547
00:26:27,640 --> 00:26:29,359
Speaker 3: pretty continuous and smooth to me.

548
00:26:30,600 --> 00:26:33,280
Speaker 1: It does seem continuous and smooth. But you know, our

549
00:26:33,320 --> 00:26:35,560
Speaker 1: intuition breaks down when we try to apply it to

550
00:26:35,640 --> 00:26:38,800
Speaker 1: things that are much much faster or much much smaller,

551
00:26:39,080 --> 00:26:41,280
Speaker 1: and they reveal that the rules of the universe are

552
00:26:41,359 --> 00:26:43,720
Speaker 1: really pretty different. Of course, when you zoom out to

553
00:26:43,800 --> 00:26:46,919
Speaker 1: things like our scale, those rules do sort of coalesce

554
00:26:47,240 --> 00:26:50,679
Speaker 1: to recover our experience. So it's amazing that you can

555
00:26:50,760 --> 00:26:52,879
Speaker 1: have like one set of rules for the very tiny

556
00:26:52,880 --> 00:26:55,520
Speaker 1: particles and it can all sort of work together to

557
00:26:55,640 --> 00:26:58,399
Speaker 1: conspire to give a very different kind of universe at

558
00:26:58,400 --> 00:26:59,119
Speaker 1: the human scale.

559
00:26:59,440 --> 00:27:01,439
Speaker 3: Right, and then maybe step us through, what are some

560
00:27:01,480 --> 00:27:04,199
Speaker 3: of the arguments for saying that time is pixelated and

561
00:27:04,240 --> 00:27:06,800
Speaker 3: what are maybe some of the arguments against it being pixelated?

562
00:27:06,880 --> 00:27:09,560
Speaker 1: Well, I think there's a few elements here. One is,

563
00:27:09,640 --> 00:27:12,159
Speaker 1: you know, what is more natural? Like what do we

564
00:27:12,240 --> 00:27:16,480
Speaker 1: expect to be the truth? Like is continuity of time

565
00:27:16,800 --> 00:27:20,239
Speaker 1: really the most natural thing? Or in the end, is

566
00:27:20,359 --> 00:27:23,720
Speaker 1: discreteness more natural? What would make more sense to us?

567
00:27:23,800 --> 00:27:26,439
Speaker 1: What's the sort of default position? And I think a

568
00:27:26,440 --> 00:27:29,200
Speaker 1: lot of people out there would assume, well, continuousness, right,

569
00:27:29,280 --> 00:27:33,159
Speaker 1: like time should flow smoothly. Seems to flow smoothly to me,

570
00:27:33,880 --> 00:27:35,800
Speaker 1: But you know that doesn't mean that that's the case.

571
00:27:36,000 --> 00:27:38,960
Speaker 1: You know, you watch TV and it seems to flow continuously,

572
00:27:39,000 --> 00:27:41,639
Speaker 1: but you know deep down that it is actually discrete.

573
00:27:41,840 --> 00:27:46,280
Speaker 1: Your television is not updating infinitely many times per second.

574
00:27:46,720 --> 00:27:49,840
Speaker 1: And that's the key, is that continuity, having continuous time,

575
00:27:50,240 --> 00:27:53,680
Speaker 1: implies a sort of infinity, and we just don't see

576
00:27:53,680 --> 00:27:56,000
Speaker 1: infinities in nature very often.

577
00:27:55,800 --> 00:27:58,280
Speaker 3: Right, Yeah. I guess like if you showed a four K,

578
00:27:58,760 --> 00:28:01,879
Speaker 3: you know, high resolution television into somebody from the you know,

579
00:28:02,200 --> 00:28:05,520
Speaker 3: tenth century, they would probably be fooled into thinking like

580
00:28:05,560 --> 00:28:08,680
Speaker 3: there's actually something magical, real going on inside of the TV.

581
00:28:08,880 --> 00:28:11,880
Speaker 3: But really it's you know, flashing, you know, twenty nine

582
00:28:11,880 --> 00:28:14,320
Speaker 3: times a second, and it's really only like two thousand

583
00:28:14,440 --> 00:28:16,080
Speaker 3: by two thousand pixels.

584
00:28:15,680 --> 00:28:19,000
Speaker 1: Exactly, and continuity is really strange, like to imagine an

585
00:28:19,080 --> 00:28:23,360
Speaker 1: infinite amount of information as the universe evolves forwards, it's

586
00:28:23,359 --> 00:28:25,680
Speaker 1: sort of like Zeno's paradox, like how do you even

587
00:28:25,720 --> 00:28:28,560
Speaker 1: get from one second to two seconds if you have

588
00:28:28,640 --> 00:28:32,040
Speaker 1: to go through an infinite number of sub seconds to

589
00:28:32,240 --> 00:28:34,320
Speaker 1: get there? You know, it feels like at some point

590
00:28:34,520 --> 00:28:37,199
Speaker 1: you got to take an actual step forward, and to

591
00:28:37,240 --> 00:28:40,320
Speaker 1: do that, you can imagine a minimum unit of time

592
00:28:40,400 --> 00:28:43,560
Speaker 1: where the universe is finally like ticking over. Otherwise, how

593
00:28:43,600 --> 00:28:46,400
Speaker 1: does that even leave the one second mark if it's

594
00:28:46,440 --> 00:28:48,920
Speaker 1: always taking a smaller and smaller and smaller and infinitely

595
00:28:48,920 --> 00:28:49,960
Speaker 1: smaller step forwards.

596
00:28:50,160 --> 00:28:52,960
Speaker 3: So you're saying that a continuous universe sort of makes

597
00:28:52,960 --> 00:28:55,320
Speaker 3: sense to us from our experience, but it starts to

598
00:28:55,320 --> 00:28:57,360
Speaker 3: break down when you really drill into it, because you

599
00:28:57,400 --> 00:28:58,520
Speaker 3: come up with infinities.

600
00:28:58,560 --> 00:29:01,080
Speaker 1: You do, you come up into infinity. And what we've

601
00:29:01,120 --> 00:29:03,720
Speaker 1: discovered is we look around us in the universe, is

602
00:29:03,760 --> 00:29:07,440
Speaker 1: that discreetness is actually much more natural. Like the things

603
00:29:07,480 --> 00:29:10,920
Speaker 1: that we see around us that seem continuous are actually discrete.

604
00:29:11,400 --> 00:29:13,800
Speaker 1: Like that chair you're sitting on right now, it seems

605
00:29:13,800 --> 00:29:16,400
Speaker 1: like it has a smooth surface, right, But it doesn't.

606
00:29:16,600 --> 00:29:19,680
Speaker 1: It's actually a lattice. A lattice is a network of

607
00:29:19,840 --> 00:29:24,160
Speaker 1: points that are tied together to approximate a smooth surface.

608
00:29:24,160 --> 00:29:26,000
Speaker 1: And if you zoom out, of course it looks smooth,

609
00:29:26,200 --> 00:29:28,440
Speaker 1: but if you zoom in far enough, it looks like

610
00:29:28,520 --> 00:29:30,920
Speaker 1: a chain link fence, you know. And that beam of

611
00:29:31,000 --> 00:29:34,800
Speaker 1: light that is shining on your plants, it's actually a

612
00:29:34,840 --> 00:29:37,920
Speaker 1: bunch of packets of photons. So the world around you,

613
00:29:37,960 --> 00:29:41,800
Speaker 1: though it seemed continuous, almost everything about it is actually discrete.

614
00:29:42,480 --> 00:29:45,680
Speaker 3: I see you're saying, because maybe the space and physical

615
00:29:45,720 --> 00:29:48,360
Speaker 3: things around this are sort of pixelated in a way

616
00:29:48,480 --> 00:29:51,240
Speaker 3: through discrete, then it would sort of make sense for

617
00:29:51,360 --> 00:29:53,160
Speaker 3: time to also be pixelated exactly.

618
00:29:53,240 --> 00:29:55,680
Speaker 1: And that's sort of a natural intuitive ist argument, right,

619
00:29:55,680 --> 00:29:57,560
Speaker 1: And it doesn't really hold that much water. It's just

620
00:29:57,840 --> 00:30:00,000
Speaker 1: sort of to get you in the mindset of things.

621
00:30:00,280 --> 00:30:04,120
Speaker 1: Maybe discrete is the more natural outcome instead of continuous, right,

622
00:30:04,160 --> 00:30:07,000
Speaker 1: So you need to be persuaded against being discrete instead

623
00:30:07,000 --> 00:30:09,160
Speaker 1: of being persuaded against it being continuous.

624
00:30:09,280 --> 00:30:09,360
Speaker 2: Right.

625
00:30:09,440 --> 00:30:11,960
Speaker 3: But I guess the universe doesn't care about what we

626
00:30:12,000 --> 00:30:14,600
Speaker 3: are our opinion of it, So what are some of

627
00:30:14,760 --> 00:30:17,959
Speaker 3: I guess more of physically robust arguments for or against

628
00:30:18,080 --> 00:30:18,880
Speaker 3: time pixilation.

629
00:30:19,120 --> 00:30:21,560
Speaker 1: Right, And so it turns out that when you drill

630
00:30:21,680 --> 00:30:25,080
Speaker 1: down into the very small time and the very small space,

631
00:30:25,480 --> 00:30:27,960
Speaker 1: what you do is you run into questions about how

632
00:30:28,080 --> 00:30:31,680
Speaker 1: gravity works. You know, in very very small spaces. Now

633
00:30:31,680 --> 00:30:33,800
Speaker 1: you have things like particles moving around, and you get

634
00:30:33,800 --> 00:30:37,160
Speaker 1: into questions of like what are the forces between those particles?

635
00:30:37,720 --> 00:30:39,760
Speaker 1: And if you have very very short time, then you

636
00:30:39,840 --> 00:30:43,440
Speaker 1: talk about very very high energy gravity kicks in, and

637
00:30:43,480 --> 00:30:45,720
Speaker 1: in the end you need to know something about how

638
00:30:45,840 --> 00:30:49,720
Speaker 1: quantum gravity works, like what are the gravitational effects for

639
00:30:49,880 --> 00:30:53,880
Speaker 1: very high energies and very short distances. And people who

640
00:30:53,880 --> 00:30:57,320
Speaker 1: are working on quantum gravity these theories of like, you know,

641
00:30:57,360 --> 00:31:00,400
Speaker 1: what is the fundamental nature of space? Is it sliced

642
00:31:00,480 --> 00:31:03,000
Speaker 1: up into pieces or not? Are there gravitons? All these

643
00:31:03,000 --> 00:31:05,680
Speaker 1: fun questions. They make a lot of arguments about space

644
00:31:05,760 --> 00:31:08,520
Speaker 1: being discrete, and we can dig into those in a minute.

645
00:31:08,600 --> 00:31:12,320
Speaker 1: And almost all of those arguments also apply to time

646
00:31:12,520 --> 00:31:16,040
Speaker 1: because space and time are very closely related. So the

647
00:31:16,080 --> 00:31:19,200
Speaker 1: physical arguments that there might be a minimum unit to space,

648
00:31:19,320 --> 00:31:22,360
Speaker 1: a lot of those same arguments you can use to

649
00:31:22,440 --> 00:31:24,360
Speaker 1: make a minimum unit of time.

650
00:31:25,560 --> 00:31:28,240
Speaker 3: Yeah, because I guess in physics there is this idea

651
00:31:28,320 --> 00:31:32,120
Speaker 3: that time is just another dimension maybe or it's like,

652
00:31:32,200 --> 00:31:34,680
Speaker 3: you know, the fourth leg in the table that is

653
00:31:34,760 --> 00:31:38,040
Speaker 3: space time, and that it's somehow like the same thing, right,

654
00:31:38,120 --> 00:31:39,960
Speaker 3: you sort of think about it that way in.

655
00:31:39,880 --> 00:31:43,120
Speaker 1: Physics, Yeah, and it's even more closely connected. Let me

656
00:31:43,120 --> 00:31:44,960
Speaker 1: give you an example. You can make a pretty simple

657
00:31:45,080 --> 00:31:48,040
Speaker 1: argument that there should be a minimum unit of space,

658
00:31:48,440 --> 00:31:50,440
Speaker 1: and then you can take the same argument and use

659
00:31:50,480 --> 00:31:53,320
Speaker 1: it for time. So it goes like this. You say, let's,

660
00:31:53,400 --> 00:31:56,239
Speaker 1: for example, try to measure a particle. What happens if

661
00:31:56,280 --> 00:31:59,520
Speaker 1: you try to measure a particle really, really precisely, so

662
00:31:59,560 --> 00:32:03,600
Speaker 1: you know it's position, like basically exactly well. Quantum mechanics says,

663
00:32:03,600 --> 00:32:06,720
Speaker 1: if you know something's position really really well, then you

664
00:32:06,760 --> 00:32:09,640
Speaker 1: don't know it's momentum very very well. Right that the

665
00:32:09,760 --> 00:32:12,719
Speaker 1: more precisely you measure the position, the less you know

666
00:32:12,800 --> 00:32:15,480
Speaker 1: about the momentum. That means that this particle now has

667
00:32:15,520 --> 00:32:19,600
Speaker 1: a huge uncertainty on its momentum, so much so that

668
00:32:19,680 --> 00:32:23,520
Speaker 1: it might have enough momentum basically enough energy to create

669
00:32:23,520 --> 00:32:26,640
Speaker 1: a black hole. And once you create a black hole,

670
00:32:26,840 --> 00:32:29,040
Speaker 1: well then you can no longer measure something about this

671
00:32:29,080 --> 00:32:32,400
Speaker 1: particle because it's inside a black hole. So like, these

672
00:32:32,480 --> 00:32:36,040
Speaker 1: very simple arguments suggest that there's a minimum distance below

673
00:32:36,120 --> 00:32:39,120
Speaker 1: which you can't measure something because if you did, it

674
00:32:39,120 --> 00:32:41,320
Speaker 1: would turn into a black hole and prevent you from

675
00:32:41,320 --> 00:32:44,520
Speaker 1: measuring it. So that's the argument about space, and you

676
00:32:44,520 --> 00:32:46,800
Speaker 1: can make a very similar argument about time.

677
00:32:47,080 --> 00:32:51,840
Speaker 3: WHOA, you just kind of skip through a few timestips there.

678
00:32:51,880 --> 00:32:54,440
Speaker 3: You're saying the argument, like one argument for space being

679
00:32:54,600 --> 00:32:57,400
Speaker 3: pixelated is that you know, if you don't have a

680
00:32:57,400 --> 00:33:01,120
Speaker 3: pixel to the universe, then basically kind of like things

681
00:33:01,160 --> 00:33:03,360
Speaker 3: can be anything at a certain level, and one of

682
00:33:03,360 --> 00:33:06,200
Speaker 3: those things could be a black hole and that's impossible

683
00:33:06,280 --> 00:33:07,960
Speaker 3: or is that's weird or are you saying that we

684
00:33:08,000 --> 00:33:08,520
Speaker 3: don't see that.

685
00:33:08,800 --> 00:33:11,640
Speaker 1: I'm saying that the universe has a mechanism to prevent

686
00:33:11,720 --> 00:33:15,000
Speaker 1: you from knowing something very precisely, because if you knew

687
00:33:15,040 --> 00:33:17,640
Speaker 1: it that precisely, it would turn into a black hole

688
00:33:17,800 --> 00:33:20,240
Speaker 1: and then censor that information. So it's sort of like

689
00:33:20,280 --> 00:33:23,960
Speaker 1: a fundamental limit there, because if you ask questions deeply enough,

690
00:33:24,080 --> 00:33:27,320
Speaker 1: basically the universe responds by covering things up with black holes.

691
00:33:27,560 --> 00:33:30,400
Speaker 3: And we don't see that, thankfully, which means that the

692
00:33:30,480 --> 00:33:34,200
Speaker 3: universe does have sort of like a fundamental maybe a

693
00:33:34,400 --> 00:33:35,440
Speaker 3: pixilation of space.

694
00:33:35,600 --> 00:33:37,800
Speaker 1: Yeah, although we can't really do this experiment, like, how

695
00:33:37,840 --> 00:33:40,920
Speaker 1: could you measure a particle with such precision that its

696
00:33:40,960 --> 00:33:43,320
Speaker 1: momentum would be so uncertain that it might turn into

697
00:33:43,360 --> 00:33:46,040
Speaker 1: like a microscopic black hole. So that's not an experiment

698
00:33:46,120 --> 00:33:47,800
Speaker 1: we could do. We'd love to do that experiment and

699
00:33:47,880 --> 00:33:51,520
Speaker 1: observe microscopic quantum black holes. Wow, we would learn so much.

700
00:33:51,680 --> 00:33:54,720
Speaker 1: It's just really sort of a thought experiment that demonstrates how,

701
00:33:55,120 --> 00:33:57,720
Speaker 1: if you ask precise enough a question, the universe sort

702
00:33:57,720 --> 00:33:59,760
Speaker 1: of counters with a black hole to prevent you from

703
00:33:59,840 --> 00:34:00,560
Speaker 1: learn about it.

704
00:34:00,600 --> 00:34:02,120
Speaker 3: But how do you know those black holes aren't there?

705
00:34:02,200 --> 00:34:04,160
Speaker 3: Maybe they are there, but they's so small you can't

706
00:34:04,160 --> 00:34:04,440
Speaker 3: see them.

707
00:34:04,520 --> 00:34:07,120
Speaker 1: Yeah, maybe they are there, but it still means that

708
00:34:07,200 --> 00:34:10,200
Speaker 1: you can't know the position of this particle to a

709
00:34:10,239 --> 00:34:13,520
Speaker 1: certain resolution because it turns into a black hole, and

710
00:34:13,560 --> 00:34:15,439
Speaker 1: you can't measure what's inside a black hole.

711
00:34:15,560 --> 00:34:18,200
Speaker 3: Okay, so that's an argument for space being pixelated. So

712
00:34:18,239 --> 00:34:20,160
Speaker 3: then how do you translate that into time.

713
00:34:20,320 --> 00:34:24,240
Speaker 1: Well, the relationship and quantum mechanics between position and momentum,

714
00:34:24,400 --> 00:34:27,840
Speaker 1: there's exactly the same relationship between energy and time. And

715
00:34:27,880 --> 00:34:29,680
Speaker 1: so if you want to make a bunch of measurements

716
00:34:29,680 --> 00:34:33,120
Speaker 1: of a particle at very very small time steps like now,

717
00:34:33,360 --> 00:34:35,800
Speaker 1: and then tend to the minus one hundred seconds later,

718
00:34:36,400 --> 00:34:40,719
Speaker 1: that introduces uncertainty in the particle's energy. So time and

719
00:34:40,840 --> 00:34:43,920
Speaker 1: energy have the same relationship in quantum mechanics as position

720
00:34:44,040 --> 00:34:47,240
Speaker 1: and momentum. It's another of the Heisenberg and certainty principles.

721
00:34:47,680 --> 00:34:50,320
Speaker 1: And so if you measure a particle's trajectory in time

722
00:34:50,520 --> 00:34:53,440
Speaker 1: very very precisely, then you create the same uncertainty in

723
00:34:53,480 --> 00:34:56,800
Speaker 1: its energy, which allows it to potentially have enough energy

724
00:34:56,800 --> 00:35:00,399
Speaker 1: to create a black hole, and boom, cosmic censorship rises again.

725
00:35:01,719 --> 00:35:04,759
Speaker 3: I see, But isn't it maybe even the same argument, right,

726
00:35:04,800 --> 00:35:07,840
Speaker 3: because I feel like momentum is sort of related to velocity,

727
00:35:07,840 --> 00:35:11,040
Speaker 3: and velocity is like distance divided by time. So really,

728
00:35:11,080 --> 00:35:14,440
Speaker 3: aren't you just making the same argument twice, except that

729
00:35:14,680 --> 00:35:17,280
Speaker 3: you know you're using the fact that time and space

730
00:35:17,360 --> 00:35:20,879
Speaker 3: and velocity are related to each other to carry over

731
00:35:21,120 --> 00:35:24,799
Speaker 3: the argument, right, Like, couldn't maybe space be pixelated but

732
00:35:24,920 --> 00:35:28,480
Speaker 3: time not pixelated? But because they're related when you're trying

733
00:35:28,520 --> 00:35:32,640
Speaker 3: to measure velocities. Then it implies that time is pixelated.

734
00:35:32,880 --> 00:35:35,680
Speaker 1: That's exactly the argument. Yeah, it says that space and

735
00:35:35,719 --> 00:35:38,840
Speaker 1: time are very closely connected, and therefore an argument you

736
00:35:38,880 --> 00:35:41,319
Speaker 1: can use to pixelate space is going to also give

737
00:35:41,320 --> 00:35:42,800
Speaker 1: you pixelization of time.

738
00:35:43,239 --> 00:35:46,040
Speaker 3: Right, But maybe time is fundamentally not pixelated. It just

739
00:35:46,120 --> 00:35:49,240
Speaker 3: appears pixelated because space is bixically.

740
00:35:49,680 --> 00:35:52,600
Speaker 1: Or maybe space is not fundamentally pixelated but time is.

741
00:35:52,840 --> 00:35:55,319
Speaker 3: Right, Yeah, that's what I mean. I feel like, yeah,

742
00:35:55,320 --> 00:35:57,439
Speaker 3: I feel like that's not really an argument for time

743
00:35:57,480 --> 00:35:58,160
Speaker 3: being pixelated.

744
00:35:58,200 --> 00:35:58,399
Speaker 2: Right.

745
00:35:58,520 --> 00:36:01,480
Speaker 1: Oh, I see that's interesting. That's a philosophical question. I

746
00:36:01,520 --> 00:36:04,160
Speaker 1: think that it shows you that the two things have

747
00:36:04,280 --> 00:36:06,520
Speaker 1: the same relationship, so it makes the most sense for

748
00:36:06,600 --> 00:36:09,560
Speaker 1: them to both be pixelated or not. In this case,

749
00:36:09,640 --> 00:36:12,360
Speaker 1: quantum mechanics suggests they both are. But I see that

750
00:36:12,440 --> 00:36:13,200
Speaker 1: other interpretation.

751
00:36:13,280 --> 00:36:15,919
Speaker 3: Yeah, all right, so there is an argument for time

752
00:36:15,960 --> 00:36:19,320
Speaker 3: being pixelated, and it has to do with quantum mechanics,

753
00:36:19,719 --> 00:36:22,680
Speaker 3: and so that sort of the uncertainty principle. So but

754
00:36:23,120 --> 00:36:25,120
Speaker 3: then have a reason of why space and time are

755
00:36:25,120 --> 00:36:26,000
Speaker 3: pixelated like that.

756
00:36:26,040 --> 00:36:28,719
Speaker 1: Yeah, And it all comes down to what happens at

757
00:36:28,719 --> 00:36:31,080
Speaker 1: these very very small distance scales when you have a

758
00:36:31,080 --> 00:36:34,480
Speaker 1: lot of energy and this is the province of quantum gravity.

759
00:36:34,680 --> 00:36:37,960
Speaker 1: And unfortunately we don't have a strong theory of quantum gravity, Like,

760
00:36:37,960 --> 00:36:41,399
Speaker 1: we don't have a theory that works that describes what

761
00:36:41,520 --> 00:36:46,000
Speaker 1: happens when gravity comes into play with quantum objects and

762
00:36:46,040 --> 00:36:48,560
Speaker 1: that gravity is strong. If we did, then it would

763
00:36:48,600 --> 00:36:51,000
Speaker 1: lay out for us what is the minimum unit of time,

764
00:36:51,080 --> 00:36:53,440
Speaker 1: what is the minimum unit of space if there is

765
00:36:53,480 --> 00:36:57,080
Speaker 1: one at all, And the different flavors of quantum gravity

766
00:36:57,280 --> 00:36:59,960
Speaker 1: that we're considering, the different ideas people are working on

767
00:37:00,160 --> 00:37:02,520
Speaker 1: for what's going on at the very smallest scale and

768
00:37:02,560 --> 00:37:05,279
Speaker 1: how this all works have sort of different approaches to

769
00:37:05,360 --> 00:37:08,319
Speaker 1: dealing with minimum distance and minimum time.

770
00:37:08,600 --> 00:37:12,239
Speaker 3: But I guess, couldn't you take the sort of theoretical

771
00:37:13,200 --> 00:37:16,080
Speaker 3: size of the space pixel and then convert that to

772
00:37:16,360 --> 00:37:19,200
Speaker 3: a time pixel because you're saying they're sort of related

773
00:37:19,280 --> 00:37:20,120
Speaker 3: or tied together.

774
00:37:20,320 --> 00:37:23,239
Speaker 1: Yes, exactly, And that's what's done, for example, in loop

775
00:37:23,360 --> 00:37:27,839
Speaker 1: quantum gravity. Loop quantum gravity says maybe the universe is

776
00:37:27,880 --> 00:37:31,800
Speaker 1: not continuous in space. It quantizes space itself, right, Instead

777
00:37:31,800 --> 00:37:35,040
Speaker 1: of trying to quantize gravity and say maybe gravity is

778
00:37:35,080 --> 00:37:38,759
Speaker 1: a quantum theory and you're exchanging gravitons, It says take

779
00:37:38,840 --> 00:37:42,680
Speaker 1: space itself and imagine it not to be smooth and continuous,

780
00:37:42,880 --> 00:37:45,160
Speaker 1: but like a big foam, like a bunch of tiny

781
00:37:45,160 --> 00:37:48,280
Speaker 1: little bubbles that are all linked together as these loops.

782
00:37:48,640 --> 00:37:50,960
Speaker 1: And so it's very natural to think about space as

783
00:37:51,000 --> 00:37:54,160
Speaker 1: having a minimum distance in loop quantum gravity. It's actually

784
00:37:54,239 --> 00:37:57,719
Speaker 1: essential because in loop quantum gravity, if space has no

785
00:37:57,920 --> 00:38:00,680
Speaker 1: minimum distance, then a bunch of the calculations they do

786
00:38:00,960 --> 00:38:04,400
Speaker 1: give nonsense results you get like infinities and craziness. So

787
00:38:04,440 --> 00:38:07,000
Speaker 1: it sort of saves the whole theory to have these

788
00:38:07,080 --> 00:38:10,560
Speaker 1: minimum values, so they rely on that, and the same

789
00:38:10,680 --> 00:38:13,800
Speaker 1: arguments can be used in loop quantum gravity to argue

790
00:38:13,840 --> 00:38:15,719
Speaker 1: for minimum steps in time.

791
00:38:15,600 --> 00:38:19,480
Speaker 3: So like maybe space is pixelated or foamy, but gravity's

792
00:38:19,480 --> 00:38:22,840
Speaker 3: maybe continues. But this would sort of merge quantum mechanics

793
00:38:22,840 --> 00:38:24,400
Speaker 3: and relativity together exactly.

794
00:38:24,800 --> 00:38:27,799
Speaker 1: And I actually asked Carlo Ravelli about this yesterday. He's

795
00:38:27,840 --> 00:38:30,520
Speaker 1: an expert in loop quantum gravity, and I asked him

796
00:38:30,640 --> 00:38:33,920
Speaker 1: if in loop quantum gravity you could have a theory

797
00:38:33,960 --> 00:38:38,239
Speaker 1: that is pixelated in space but continuous in time, or

798
00:38:38,480 --> 00:38:42,120
Speaker 1: if you absolutely had to have discrete time as well,

799
00:38:42,640 --> 00:38:45,160
Speaker 1: And he said that he thinks that the theory is

800
00:38:45,200 --> 00:38:48,680
Speaker 1: on solid footing from the point of view of space

801
00:38:48,719 --> 00:38:52,359
Speaker 1: pixels that you can represent areas having discrete units. So

802
00:38:52,360 --> 00:38:54,680
Speaker 1: that's very solid. He's very confident about that, and he

803
00:38:54,680 --> 00:38:57,560
Speaker 1: says you can do something similar with time, but there

804
00:38:57,560 --> 00:39:00,400
Speaker 1: are some complicated jumps you have to make in the argument,

805
00:39:00,440 --> 00:39:03,640
Speaker 1: and he wasn't one hundred percent confident in it. But

806
00:39:04,160 --> 00:39:07,400
Speaker 1: he also said that he would be very surprised if

807
00:39:07,480 --> 00:39:10,120
Speaker 1: anything that included time and as a measurement could really

808
00:39:10,200 --> 00:39:12,440
Speaker 1: have a continuous spectrum, because from his point of view,

809
00:39:12,520 --> 00:39:16,640
Speaker 1: the world is quantum. Everything about the universe is discrete,

810
00:39:16,840 --> 00:39:18,960
Speaker 1: and he would be very surprised if time was any different.

811
00:39:19,080 --> 00:39:24,080
Speaker 3: It seems like the theorists don't think time is continuous,

812
00:39:24,120 --> 00:39:26,800
Speaker 3: that it's maybe more likely or would make more sense,

813
00:39:27,120 --> 00:39:28,040
Speaker 3: that it's pixelated.

814
00:39:28,160 --> 00:39:30,680
Speaker 1: Exactly in luke qantum gravity, it makes most sense for

815
00:39:30,960 --> 00:39:34,399
Speaker 1: time to be pixelated in the same way that space is.

816
00:39:34,960 --> 00:39:37,960
Speaker 1: Now there are other theories of quantum gravity, theories like

817
00:39:38,080 --> 00:39:41,800
Speaker 1: string theory, that have a different approach on minimum units

818
00:39:41,800 --> 00:39:42,240
Speaker 1: of time.

819
00:39:42,480 --> 00:39:45,000
Speaker 3: Well, I guess maybe the question that a lot of

820
00:39:45,040 --> 00:39:47,319
Speaker 3: people might be thinking at this point is that would

821
00:39:47,320 --> 00:39:50,120
Speaker 3: it make sense for time to be pixelated or could

822
00:39:50,160 --> 00:39:51,200
Speaker 3: it still be continuous.

823
00:39:51,239 --> 00:39:53,799
Speaker 1: On one hand, it makes perfect sense for time to

824
00:39:53,920 --> 00:39:56,960
Speaker 1: be chopped up in a minimum munist because, as we say,

825
00:39:57,080 --> 00:40:00,399
Speaker 1: quantum mechanics tells us that the universe is discreet, right.

826
00:40:00,640 --> 00:40:03,359
Speaker 1: But there's a problem when you do that. Introducing like

827
00:40:03,400 --> 00:40:06,880
Speaker 1: a minimum time scale or a minimum length scale is

828
00:40:06,920 --> 00:40:10,400
Speaker 1: tricky because we know from the other great theory of

829
00:40:10,440 --> 00:40:14,439
Speaker 1: the universe relativity, that things like distances and times are

830
00:40:14,480 --> 00:40:17,200
Speaker 1: not universal. So like, for example, if we're in the

831
00:40:17,239 --> 00:40:21,840
Speaker 1: laboratory and we're measuring the universe down to its minimum distance,

832
00:40:22,200 --> 00:40:24,560
Speaker 1: we have some pair of tweezers that can work at

833
00:40:24,560 --> 00:40:27,160
Speaker 1: the plank length. For example, what happens if somebody is

834
00:40:27,200 --> 00:40:30,160
Speaker 1: zooming by on a spaceship and they're watching our experiment,

835
00:40:30,640 --> 00:40:34,200
Speaker 1: They see us like length contracted. They see everything shortened

836
00:40:34,640 --> 00:40:37,040
Speaker 1: because they're moving at a fast speed relative to us.

837
00:40:37,320 --> 00:40:40,000
Speaker 1: So then they would be seeing things at smaller than

838
00:40:40,000 --> 00:40:44,000
Speaker 1: the minimum distance. So like, having a minimum distance breaks

839
00:40:44,120 --> 00:40:46,680
Speaker 1: special relativity in a really important way.

840
00:40:46,880 --> 00:40:49,759
Speaker 3: Wait, what do you mean? It doesn't break relativity in

841
00:40:49,800 --> 00:40:53,239
Speaker 3: a way. It just means that it's al sort a relative, right,

842
00:40:53,280 --> 00:40:56,200
Speaker 3: Like to someone moving at a certain speed. The minimum

843
00:40:56,200 --> 00:40:58,440
Speaker 3: distance in the universe would be this much and to

844
00:40:58,520 --> 00:41:00,920
Speaker 3: someone not moving at that t it would be this much,

845
00:41:00,960 --> 00:41:02,600
Speaker 3: but it would still have a minimum distance.

846
00:41:02,680 --> 00:41:05,520
Speaker 1: Yeah, if you assert the primacy of relativity, then you're

847
00:41:05,560 --> 00:41:08,520
Speaker 1: giving up an absolute minimum distance. You're saying minimum distance

848
00:41:08,560 --> 00:41:11,000
Speaker 1: is not really minimum, it's relative. If you start from

849
00:41:11,000 --> 00:41:13,800
Speaker 1: the other direction, you say, no, there's an absolute minimum

850
00:41:13,800 --> 00:41:17,160
Speaker 1: distance anybody can measure, no matter how their speed. Then

851
00:41:17,200 --> 00:41:19,560
Speaker 1: that would break relativity. So you can't have the two

852
00:41:19,600 --> 00:41:21,960
Speaker 1: things at the same time. You can have one, but

853
00:41:21,960 --> 00:41:23,200
Speaker 1: then it breaks the other one.

854
00:41:23,880 --> 00:41:26,920
Speaker 3: So you're saying that a pixelated universe, even a space

855
00:41:27,160 --> 00:41:30,880
Speaker 3: pixelated universe, would break relativity, or it's not consistent with

856
00:41:30,960 --> 00:41:32,000
Speaker 3: relativity exactly.

857
00:41:32,080 --> 00:41:35,719
Speaker 1: It's inconsistent with special relativity, which we thought until now

858
00:41:35,960 --> 00:41:38,719
Speaker 1: was like pretty well established, Like we have measured it

859
00:41:38,760 --> 00:41:41,359
Speaker 1: out the wazoo and it works pretty well. But you know,

860
00:41:41,640 --> 00:41:44,719
Speaker 1: these directions in quantum gravity really do suggest that there

861
00:41:44,800 --> 00:41:49,400
Speaker 1: might be space pixels. But that's fundamentally inconsistent with special relativity.

862
00:41:49,680 --> 00:41:51,480
Speaker 1: So that's a big puzzle to work out.

863
00:41:51,600 --> 00:41:55,439
Speaker 3: I see, save relativity is true, as Einstein said, then

864
00:41:55,480 --> 00:41:58,000
Speaker 3: the universe is not pixelated, or it can't be pixelated,

865
00:41:58,120 --> 00:41:59,719
Speaker 3: or it doesn't make sense for it to be pixelated.

866
00:41:59,800 --> 00:42:03,040
Speaker 1: Yeah, and you know we're focusing today on pixels in time.

867
00:42:03,360 --> 00:42:06,600
Speaker 1: There's another consequence of having pixels in time. You know,

868
00:42:06,680 --> 00:42:10,480
Speaker 1: if the universe is not continuous, if it's discrete, right,

869
00:42:10,480 --> 00:42:12,439
Speaker 1: if you can have like time equals one point five

870
00:42:12,480 --> 00:42:15,320
Speaker 1: seconds and one point six seconds, but not time equals

871
00:42:15,360 --> 00:42:17,839
Speaker 1: one point five to five seconds, that means the time

872
00:42:17,920 --> 00:42:20,680
Speaker 1: is not smooth and the universe sort of cares what

873
00:42:20,880 --> 00:42:23,000
Speaker 1: time you're at. That you can't like do the same

874
00:42:23,040 --> 00:42:26,440
Speaker 1: experiment halfway between time pixels, And that actually has a

875
00:42:26,440 --> 00:42:29,000
Speaker 1: really important consequence. As we've talked about once on the

876
00:42:29,040 --> 00:42:33,080
Speaker 1: podcast before. This basic concept that energy in the universe

877
00:42:33,200 --> 00:42:36,680
Speaker 1: is conserved that relies on an assumption, and that assumption

878
00:42:37,239 --> 00:42:39,880
Speaker 1: is that space has a symmetry in time, that space

879
00:42:40,120 --> 00:42:43,160
Speaker 1: always looks the same, that the universe doesn't care when

880
00:42:43,239 --> 00:42:46,560
Speaker 1: you do an experiment. It just could happen now or

881
00:42:46,640 --> 00:42:50,160
Speaker 1: later or yesterday. You know, it doesn't care about your deadlines.

882
00:42:50,280 --> 00:42:53,280
Speaker 1: And discrete time breaks that it says there are special

883
00:42:53,360 --> 00:42:56,520
Speaker 1: values of time. That makes sense, and so that would

884
00:42:56,520 --> 00:42:59,840
Speaker 1: throw conservation of energy out the window. So if you

885
00:42:59,880 --> 00:43:03,360
Speaker 1: have discrete units of time, then basically you break conservation

886
00:43:03,440 --> 00:43:03,920
Speaker 1: of energy.

887
00:43:04,040 --> 00:43:06,520
Speaker 3: WHOA, that seems like an important rule in the universe.

888
00:43:06,640 --> 00:43:08,800
Speaker 1: Yeah, so we're breaking all the rules today.

889
00:43:08,880 --> 00:43:11,200
Speaker 3: All right, Well, I guess what I'm getting is that

890
00:43:11,520 --> 00:43:14,319
Speaker 3: it makes sense for time to be pixelated by some

891
00:43:14,520 --> 00:43:17,920
Speaker 3: arguments like a loop quantum theory and thinking about space

892
00:43:17,960 --> 00:43:20,560
Speaker 3: being pixelated, but it doesn't make any sense for it

893
00:43:20,600 --> 00:43:23,120
Speaker 3: to be pixelated from other points of view like relativity

894
00:43:23,640 --> 00:43:26,080
Speaker 3: or conservation of energy. All right, well, let's get into

895
00:43:26,120 --> 00:43:28,480
Speaker 3: our last question, which is how would we even know

896
00:43:28,920 --> 00:43:31,880
Speaker 3: if time is pixelated? Could we devise an experiment to

897
00:43:31,920 --> 00:43:34,600
Speaker 3: tell us whether or not it's true or whether it'll

898
00:43:34,640 --> 00:43:37,439
Speaker 3: be a mystery until the end of time. But first,

899
00:43:37,520 --> 00:43:38,800
Speaker 3: let's take another quick break.

900
00:43:43,280 --> 00:43:45,080
Speaker 1: When you pop a piece of cheese into your mouth

901
00:43:45,160 --> 00:43:48,320
Speaker 1: or enjoy a rich spoonful of Greek yogurt, you're probably

902
00:43:48,360 --> 00:43:52,400
Speaker 1: not thinking about the environmental impact of each and every bite.

903
00:43:52,440 --> 00:43:55,040
Speaker 1: But the people in the dairy industry are us. Dairy

904
00:43:55,080 --> 00:43:59,360
Speaker 1: has set themselves some ambitious sustainability goals, including being greenhouse

905
00:43:59,400 --> 00:44:02,000
Speaker 1: gas neutral by twenty to fifty. That's why they're working

906
00:44:02,040 --> 00:44:04,400
Speaker 1: hard every day to find new ways to reduce waste,

907
00:44:04,440 --> 00:44:08,640
Speaker 1: conserve natural resources, and drive down greenhouse gas emissions. Take water.

908
00:44:08,680 --> 00:44:11,759
Speaker 1: For example, most dairy farms reuse water up to four

909
00:44:11,840 --> 00:44:15,279
Speaker 1: times The same water cools the milk, cleans equipment, washes

910
00:44:15,320 --> 00:44:18,160
Speaker 1: the barn, and irrigates the crops. How is US Dairy

911
00:44:18,160 --> 00:44:21,919
Speaker 1: tackling greenhouse gases? Many farms use anaerobic digestors that turn

912
00:44:21,960 --> 00:44:25,880
Speaker 1: the methane from maneure into renewable energy that can power farms, towns,

913
00:44:25,880 --> 00:44:28,000
Speaker 1: and electric cars. So the next time you grab a

914
00:44:28,000 --> 00:44:30,040
Speaker 1: slice of pizza or lick an ice cream cone, know

915
00:44:30,080 --> 00:44:32,799
Speaker 1: that dairy farmers and processors around the country are using

916
00:44:32,800 --> 00:44:36,319
Speaker 1: the latest practices and innovations to provide the nutrient dense

917
00:44:36,440 --> 00:44:39,160
Speaker 1: dairy products we love with less of an impact. Visit

918
00:44:39,239 --> 00:44:42,040
Speaker 1: usdairy dot com slash sustainability to learn more.

919
00:44:42,200 --> 00:44:44,960
Speaker 2: People are driven by the search for better, but when

920
00:44:45,000 --> 00:44:47,319
Speaker 2: it comes to hiring, the best way to search for

921
00:44:47,360 --> 00:44:51,280
Speaker 2: a candidate isn't to search at all. Don't search match

922
00:44:51,600 --> 00:44:55,160
Speaker 2: with Indeed. The hiring process can be slow and overwhelming.

923
00:44:55,520 --> 00:44:59,560
Speaker 2: Simplify hiring with Indeed. Indeed is your matching and hiring

924
00:44:59,560 --> 00:45:03,240
Speaker 2: platform with over three hundred and fifty million global monthly

925
00:45:03,360 --> 00:45:06,759
Speaker 2: visitors according to Indeed Data, and a matching engine that

926
00:45:06,880 --> 00:45:11,160
Speaker 2: helps you find quality candidates fast. Ditch the busy work.

927
00:45:11,600 --> 00:45:15,120
Speaker 2: Use indeed for scheduling, screening, and messaging so you can

928
00:45:15,120 --> 00:45:18,680
Speaker 2: connect with candidates faster. Join more than three point five

929
00:45:18,760 --> 00:45:22,600
Speaker 2: million businesses worldwide that use indeed to hire great talent.

930
00:45:22,840 --> 00:45:25,839
Speaker 2: Fast Listeners of this show will get a seventy five

931
00:45:25,880 --> 00:45:29,319
Speaker 2: dollars sponsored job credit to get your jobs more visibility

932
00:45:29,360 --> 00:45:34,960
Speaker 2: at indeed dot com slash po d katz twelve. That's

933
00:45:35,040 --> 00:45:41,320
Speaker 2: Indeed dot com slash pod katz twelve. Terms and conditions apply.

934
00:45:42,440 --> 00:45:42,640
Speaker 3: Hi.

935
00:45:42,760 --> 00:45:46,360
Speaker 5: I'm David Eagleman from the podcast Inner Cosmos, which recently

936
00:45:46,440 --> 00:45:49,480
Speaker 5: hit the number one science podcast in America. I mean

937
00:45:49,560 --> 00:45:53,319
Speaker 5: neuroscientists at Stanford, and I've spent my career exploring the

938
00:45:53,440 --> 00:45:55,000
Speaker 5: three pound universe.

939
00:45:54,640 --> 00:45:55,400
Speaker 1: In our heads.

940
00:45:55,719 --> 00:45:56,840
Speaker 2: We're looking at a whole new.

941
00:45:56,760 --> 00:46:00,680
Speaker 5: Series of episodes this season to understand why and how

942
00:46:01,040 --> 00:46:03,719
Speaker 5: our lives look the way they do. Why does your

943
00:46:03,800 --> 00:46:07,480
Speaker 5: memory drift so much? Why is it so hard to

944
00:46:07,560 --> 00:46:11,200
Speaker 5: keep a secret, When should you not trust your intuition?

945
00:46:12,000 --> 00:46:15,319
Speaker 5: Why do brains so easily fall for magic tricks? And

946
00:46:15,360 --> 00:46:19,360
Speaker 5: why do they love conspiracy theories? I'm hitting these questions

947
00:46:19,400 --> 00:46:22,880
Speaker 5: and hundreds more because the more we know about what's

948
00:46:22,960 --> 00:46:26,520
Speaker 5: running under the hood better we can steer our lives.

949
00:46:27,160 --> 00:46:30,520
Speaker 5: Join me weekly to explore the relationship between your brain

950
00:46:30,680 --> 00:46:35,239
Speaker 5: and your life by digging into unexpected questions. Listen to

951
00:46:35,280 --> 00:46:39,319
Speaker 5: Inner Cosmos with David Eagleman on the iHeartRadio app, Apple Podcasts,

952
00:46:39,400 --> 00:46:41,120
Speaker 5: or wherever you get your podcasts.

953
00:46:42,960 --> 00:46:46,120
Speaker 13: Parents, are you looking for a screen free, engaging way

954
00:46:46,160 --> 00:46:48,160
Speaker 13: to teach your kids the Bible, one that's easy to

955
00:46:48,239 --> 00:46:52,640
Speaker 13: understand and enjoyable for multiple ages. Kids Bible Stories Podcast

956
00:46:52,719 --> 00:46:55,200
Speaker 13: is here to help. I created this for my own

957
00:46:55,280 --> 00:46:58,160
Speaker 13: children and it's now a favorite among thousands of families.

958
00:46:58,680 --> 00:47:01,840
Speaker 13: Kids love the vivid image, injury scriptures, and sound effects,

959
00:47:01,960 --> 00:47:05,520
Speaker 13: while parents appreciate the apply section for meaningful conversations. We

960
00:47:05,640 --> 00:47:09,160
Speaker 13: have hundreds and hundreds of beautiful episodes that bring the

961
00:47:09,160 --> 00:47:12,600
Speaker 13: Bible to life when you simply press play. It's a

962
00:47:12,800 --> 00:47:16,360
Speaker 13: sound and practical resource that walks alongside you as you

963
00:47:16,440 --> 00:47:19,920
Speaker 13: teach your kids. We want kids to see how incredible

964
00:47:19,960 --> 00:47:23,560
Speaker 13: God's word is in an engaging and memorable way with

965
00:47:23,719 --> 00:47:28,200
Speaker 13: Kids Bible Stories Podcast. Listen to Kids Bible Stories Podcast

966
00:47:28,239 --> 00:47:31,439
Speaker 13: on the iHeartRadio app, Apple podcasts, or wherever you get

967
00:47:31,440 --> 00:47:32,239
Speaker 13: your podcasts.

968
00:47:40,600 --> 00:47:43,720
Speaker 3: All Right is Time Pixelated I guess, Daniel, the biggest

969
00:47:43,800 --> 00:47:47,280
Speaker 3: question is how would we know, Like, are we trapped

970
00:47:47,280 --> 00:47:50,400
Speaker 3: in the matrix and we think time smooth and continuous,

971
00:47:50,440 --> 00:47:52,400
Speaker 3: and are we always going to be trapped in this

972
00:47:52,520 --> 00:47:54,880
Speaker 3: matrix thinking that it's continuous or we'll be ever to

973
00:47:54,880 --> 00:47:57,080
Speaker 3: be able to step outside of time and see that

974
00:47:57,120 --> 00:47:59,240
Speaker 3: it's actually you know, discrete.

975
00:47:59,480 --> 00:48:02,680
Speaker 1: Unfortunately, we might never know. You know, it might be

976
00:48:02,880 --> 00:48:06,400
Speaker 1: that time is continuous and we are hunting forever for

977
00:48:06,480 --> 00:48:09,760
Speaker 1: the minimum unit and not finding it. But not finding

978
00:48:09,800 --> 00:48:12,440
Speaker 1: it doesn't mean it doesn't exist. There's a possibility that

979
00:48:12,480 --> 00:48:15,560
Speaker 1: we could always be frustrated. It's sort of like, you know,

980
00:48:15,680 --> 00:48:18,600
Speaker 1: finding the smallest particle. You never really know if it's

981
00:48:18,640 --> 00:48:22,080
Speaker 1: the smallest particle or if there's a smaller particle inside

982
00:48:22,080 --> 00:48:24,040
Speaker 1: it that's so small you can't see it.

983
00:48:24,160 --> 00:48:27,280
Speaker 3: But that would be sort of a limitation of our technology,

984
00:48:27,560 --> 00:48:30,120
Speaker 3: right or is that always going to be true because

985
00:48:30,440 --> 00:48:32,759
Speaker 3: you know, you sort of like you can't prove a

986
00:48:32,840 --> 00:48:36,200
Speaker 3: negative kind of or you know, since infinity is forever,

987
00:48:36,440 --> 00:48:38,560
Speaker 3: there's no way we can never get down to a

988
00:48:38,640 --> 00:48:41,279
Speaker 3: small enough level to be sure that it's not pixelated.

989
00:48:41,360 --> 00:48:43,880
Speaker 1: Yeah, I think there are ways that we could convince

990
00:48:43,960 --> 00:48:47,360
Speaker 1: ourselves that it probably is pixelated, but it'd be pretty

991
00:48:47,400 --> 00:48:50,000
Speaker 1: hard to prove that it's not. You know, it'd be

992
00:48:50,000 --> 00:48:53,160
Speaker 1: pretty hard to prove that it's infinitely continuous. I think

993
00:48:53,200 --> 00:48:56,200
Speaker 1: you'd need some pretty elaborate theory of physics that requires

994
00:48:56,239 --> 00:48:58,839
Speaker 1: that that has some other consequences somehow that I can't

995
00:48:58,880 --> 00:49:01,399
Speaker 1: even imagine that you could then confirm. So I think

996
00:49:01,440 --> 00:49:04,440
Speaker 1: it's easier to prove that it is discreete than to

997
00:49:04,480 --> 00:49:05,640
Speaker 1: prove that it's continuous.

998
00:49:05,719 --> 00:49:08,000
Speaker 3: But you just gave me some arguments for why space

999
00:49:08,080 --> 00:49:11,480
Speaker 3: might be pixilated, right with the whole infinitely small black holes.

1000
00:49:11,520 --> 00:49:13,120
Speaker 3: Can then we come up with a theory or some

1001
00:49:13,200 --> 00:49:16,160
Speaker 3: sort of way or some sort of consequence over the

1002
00:49:16,160 --> 00:49:18,600
Speaker 3: theory of the equations to say that, look it, time

1003
00:49:18,680 --> 00:49:19,680
Speaker 3: has to be pixelated.

1004
00:49:19,800 --> 00:49:22,399
Speaker 1: Yeah, exactly. I think that's the best way forward. If

1005
00:49:22,400 --> 00:49:25,640
Speaker 1: we come up with a rigorous theory of quantum gravity

1006
00:49:25,960 --> 00:49:29,040
Speaker 1: and it requires, because of its very nature, you know,

1007
00:49:29,080 --> 00:49:31,960
Speaker 1: for time to be pixelated, and then that theory holds

1008
00:49:31,960 --> 00:49:34,320
Speaker 1: together and makes a bunch of predictions, you know, maybe

1009
00:49:34,360 --> 00:49:37,640
Speaker 1: not directly showing us the clock ticks of the universe,

1010
00:49:38,200 --> 00:49:41,960
Speaker 1: but having other consequences of that in its inherent nature.

1011
00:49:42,239 --> 00:49:44,920
Speaker 1: Then we can be pretty confident that the universe is

1012
00:49:45,000 --> 00:49:46,520
Speaker 1: pixelated when it comes to time.

1013
00:49:46,719 --> 00:49:49,439
Speaker 3: All right, well, then how could we hope to prove

1014
00:49:49,480 --> 00:49:51,759
Speaker 3: that it is pixelated? Then what kinds of experiments can

1015
00:49:51,800 --> 00:49:54,040
Speaker 3: we make or what experiments have been made.

1016
00:49:54,000 --> 00:49:57,480
Speaker 1: So so far? The edge of our knowledge is basically

1017
00:49:57,520 --> 00:50:02,040
Speaker 1: particle colliders. Particle colliders smash particles together at very very

1018
00:50:02,120 --> 00:50:04,680
Speaker 1: high energy, which is the same thing as saying that

1019
00:50:04,719 --> 00:50:08,480
Speaker 1: they're studying things at very very small distance scales. Remember

1020
00:50:08,520 --> 00:50:13,319
Speaker 1: that the energy of an object controls its effective wave function, right,

1021
00:50:13,320 --> 00:50:15,960
Speaker 1: the width of its wave function. A really really high

1022
00:50:16,080 --> 00:50:19,680
Speaker 1: energy object is one with very high frequency, which means

1023
00:50:19,680 --> 00:50:22,480
Speaker 1: that you can localize it to very specific place. And

1024
00:50:22,520 --> 00:50:25,440
Speaker 1: so with very high energy particles you can probe things

1025
00:50:25,760 --> 00:50:28,920
Speaker 1: really small distances. Or think about it another way, the

1026
00:50:29,000 --> 00:50:31,360
Speaker 1: more you crank up the energy of your particle colliders,

1027
00:50:31,480 --> 00:50:34,560
Speaker 1: the smaller the particles you can discover because you can

1028
00:50:34,600 --> 00:50:37,280
Speaker 1: like break them open and see small things inside them.

1029
00:50:37,640 --> 00:50:39,920
Speaker 1: So we've made a lot of progress there, and we

1030
00:50:39,960 --> 00:50:42,440
Speaker 1: are studying things that are like ten to the minus

1031
00:50:42,520 --> 00:50:46,480
Speaker 1: twenty meters wide, you know, quirks that are inside the proton.

1032
00:50:46,719 --> 00:50:49,400
Speaker 1: So that sounds pretty small, right, It's like ten to

1033
00:50:49,440 --> 00:50:52,360
Speaker 1: the minus twenty meters is a very small slice of

1034
00:50:52,400 --> 00:50:55,520
Speaker 1: the universe. But you know it's ten to the fifteen

1035
00:50:55,840 --> 00:50:58,680
Speaker 1: times bigger than what we think is the Plank scale,

1036
00:50:58,719 --> 00:51:01,719
Speaker 1: which is ten to the minus third five meters, And

1037
00:51:01,760 --> 00:51:02,920
Speaker 1: that's a big ratio.

1038
00:51:03,360 --> 00:51:06,120
Speaker 3: Right, Yeah, you just need more money, Daniel, Just ask

1039
00:51:06,160 --> 00:51:08,040
Speaker 3: the taxpayers for more money.

1040
00:51:08,160 --> 00:51:10,400
Speaker 1: Yeah, we should siphon funds out of your ten billion

1041
00:51:10,440 --> 00:51:11,520
Speaker 1: dollar comics project.

1042
00:51:11,680 --> 00:51:14,160
Speaker 3: Oh no, no, no, no, you can't touch that. Some things

1043
00:51:14,160 --> 00:51:17,320
Speaker 3: are more important than understanding the nature of the universe.

1044
00:51:17,480 --> 00:51:17,919
Speaker 1: That's right.

1045
00:51:18,080 --> 00:51:20,960
Speaker 3: That's a limiting distance, right, that's not quite the limit

1046
00:51:21,000 --> 00:51:23,040
Speaker 3: in time? Or is it the equivalent you're saying.

1047
00:51:23,120 --> 00:51:26,359
Speaker 1: I'm saying they're equivalent because these experiments also happen really

1048
00:51:26,400 --> 00:51:29,040
Speaker 1: really fast, and to be really really fast you have

1049
00:51:29,080 --> 00:51:32,120
Speaker 1: to have really really high energy also, and so fundamentally,

1050
00:51:32,160 --> 00:51:36,240
Speaker 1: these high energy experiments are probing short times and small

1051
00:51:36,280 --> 00:51:40,360
Speaker 1: distances sort of at the same time. But unfortunately they're

1052
00:51:40,480 --> 00:51:44,000
Speaker 1: like way too weak to probe really the fundamental nature

1053
00:51:44,000 --> 00:51:45,920
Speaker 1: of the universe. And to make them big enough and

1054
00:51:46,040 --> 00:51:49,239
Speaker 1: powerful enough to probe that distance scale, you'd need like

1055
00:51:49,320 --> 00:51:52,040
Speaker 1: a collider the size of the Solar System or maybe

1056
00:51:52,040 --> 00:51:54,919
Speaker 1: even the galaxy. So it's not even something we even

1057
00:51:55,040 --> 00:51:56,320
Speaker 1: imagine asking for.

1058
00:51:56,480 --> 00:51:58,520
Speaker 3: A little too expensive to make a collider of the

1059
00:51:58,560 --> 00:52:01,080
Speaker 3: size of the Solar system. So then what can we do?

1060
00:52:01,120 --> 00:52:04,040
Speaker 3: What are alternatives to break in the bank here to

1061
00:52:04,200 --> 00:52:04,840
Speaker 3: find the answer?

1062
00:52:04,920 --> 00:52:07,719
Speaker 1: So people are trying to come up with tabletop experiments,

1063
00:52:07,760 --> 00:52:10,400
Speaker 1: things you can do in a single laboratory to probe

1064
00:52:10,719 --> 00:52:14,000
Speaker 1: either directly like the discrete nature of space and time,

1065
00:52:14,520 --> 00:52:17,160
Speaker 1: or to try to like do really subtle experiments to

1066
00:52:17,239 --> 00:52:21,800
Speaker 1: understand quantum gravity. There's some really cool ideas developing experiments

1067
00:52:21,840 --> 00:52:24,520
Speaker 1: that might really work and could actually help us understand

1068
00:52:24,520 --> 00:52:27,040
Speaker 1: how things work at the smallest scale. The first idea

1069
00:52:27,120 --> 00:52:30,360
Speaker 1: was proposed about ten years ago by Beckenstein. He's a

1070
00:52:30,400 --> 00:52:32,960
Speaker 1: guy who worked closely with Stephen Hawking to develop the

1071
00:52:33,239 --> 00:52:36,080
Speaker 1: understanding of black holes that we have today, so definitely

1072
00:52:36,120 --> 00:52:39,160
Speaker 1: a smart person. And he had this crazy idea of

1073
00:52:39,440 --> 00:52:43,000
Speaker 1: shooting a single photon at a crystal. And the idea

1074
00:52:43,239 --> 00:52:45,239
Speaker 1: is that what happens when you shoot a photon at

1075
00:52:45,239 --> 00:52:48,440
Speaker 1: a crystal it's a quantum object. Either it gets absorbed

1076
00:52:48,760 --> 00:52:51,520
Speaker 1: or it doesn't. And if it gets absorbed, then you

1077
00:52:51,560 --> 00:52:54,760
Speaker 1: know where does its momentum go like pushes the crystal

1078
00:52:54,880 --> 00:52:57,400
Speaker 1: a little bit, the same way we talk about, you know,

1079
00:52:57,440 --> 00:53:01,120
Speaker 1: like solar sales, shooting photons from the sun and hitting

1080
00:53:01,160 --> 00:53:03,440
Speaker 1: a sale and pushing a spacecraft forward. This is like

1081
00:53:03,480 --> 00:53:05,840
Speaker 1: a mini version of that, where you shoot a single

1082
00:53:05,880 --> 00:53:08,600
Speaker 1: photon at a crystal and if it gets absorbed, it

1083
00:53:08,640 --> 00:53:11,360
Speaker 1: needs to like move forward a little bit. And so

1084
00:53:11,440 --> 00:53:14,239
Speaker 1: the idea is to like tune the energy of the

1085
00:53:14,280 --> 00:53:18,759
Speaker 1: photon so it matches like the basic minimum distance of

1086
00:53:18,880 --> 00:53:22,880
Speaker 1: the universe, so you can measure somehow if this crystal

1087
00:53:22,960 --> 00:53:24,879
Speaker 1: like slides forward a tiny bit.

1088
00:53:25,880 --> 00:53:28,560
Speaker 3: All right, So you're shooting a photon, and I guess

1089
00:53:28,600 --> 00:53:31,319
Speaker 3: you make the photon small enough that maybe you'll see

1090
00:53:31,320 --> 00:53:33,799
Speaker 3: that jump between like oh it hit the crystal and

1091
00:53:34,160 --> 00:53:36,000
Speaker 3: oh it didn't hit the crystal, which would sort of

1092
00:53:36,040 --> 00:53:38,840
Speaker 3: tell you that the universe is not continuous. Is that

1093
00:53:38,920 --> 00:53:40,439
Speaker 3: kind of what the experiment would be doing.

1094
00:53:40,640 --> 00:53:43,600
Speaker 1: Yeah, that's the idea that you have like lots of

1095
00:53:43,600 --> 00:53:46,680
Speaker 1: these little photons and they're interacting with elements of the crystal.

1096
00:53:46,880 --> 00:53:49,480
Speaker 1: If you tune it just right, they have like just

1097
00:53:49,600 --> 00:53:54,400
Speaker 1: enough energy to move it one like quantum universe step forwards.

1098
00:53:54,520 --> 00:53:57,319
Speaker 1: And so this is an idea that Beckenstein proposed about

1099
00:53:57,400 --> 00:53:59,960
Speaker 1: ten years ago, and some people thought it was very exciting, like,

1100
00:54:00,080 --> 00:54:03,000
Speaker 1: oh wow, maybe we could measure quantum gravity on a tabletop.

1101
00:54:03,080 --> 00:54:05,719
Speaker 1: Other folks I've asked have frankly said it's probably bull

1102
00:54:05,719 --> 00:54:06,880
Speaker 1: crap and would never work.

1103
00:54:07,200 --> 00:54:09,600
Speaker 3: I see, all right, so that's a no no. What

1104
00:54:09,640 --> 00:54:11,719
Speaker 3: are other ways in which we could maybe figure out

1105
00:54:11,719 --> 00:54:12,719
Speaker 3: if time is pixelated?

1106
00:54:12,760 --> 00:54:15,400
Speaker 1: Well, really, I think the most promising way to figure

1107
00:54:15,400 --> 00:54:18,000
Speaker 1: out if time is pixelated is to try to get

1108
00:54:18,040 --> 00:54:21,680
Speaker 1: these theories of quantum gravity, to understand, you know, basically

1109
00:54:21,719 --> 00:54:24,160
Speaker 1: the nature of space and time itself, and to do

1110
00:54:24,239 --> 00:54:26,799
Speaker 1: it all at once. So these aren't experiments where you

1111
00:54:26,800 --> 00:54:29,440
Speaker 1: can see the universe take forward in time, but they

1112
00:54:29,520 --> 00:54:32,560
Speaker 1: are experiments that might help reveal the very nature of

1113
00:54:32,600 --> 00:54:35,600
Speaker 1: space and time, which would give us clues about whether

1114
00:54:35,680 --> 00:54:38,680
Speaker 1: space and time are pixelated. And the way to make

1115
00:54:38,719 --> 00:54:42,120
Speaker 1: progress there is to try to see gravity having influence

1116
00:54:42,200 --> 00:54:46,000
Speaker 1: on individual particles, because we don't know how gravity works

1117
00:54:46,000 --> 00:54:47,719
Speaker 1: when it comes to little particles, like we know how

1118
00:54:47,760 --> 00:54:50,640
Speaker 1: gravity works when it comes to the Earth and the Moon,

1119
00:54:50,960 --> 00:54:53,360
Speaker 1: or the Earth and the Sun for example, or even

1120
00:54:53,400 --> 00:54:56,680
Speaker 1: black holes, but we don't know what happens between two particles.

1121
00:54:57,000 --> 00:54:59,799
Speaker 1: Are they like passing little gravitons back and forth? Are

1122
00:54:59,840 --> 00:55:03,239
Speaker 1: they bending space? Is space discrete? There? Like? What we

1123
00:55:03,320 --> 00:55:07,200
Speaker 1: need to do is see really strong gravitational effects on particles.

1124
00:55:07,400 --> 00:55:10,120
Speaker 1: The problem, of course, is that particles have almost no

1125
00:55:10,239 --> 00:55:13,560
Speaker 1: mass and so they have almost no gravity. But we've

1126
00:55:13,560 --> 00:55:17,680
Speaker 1: gotten pretty good recently at building larger quantum objects, like

1127
00:55:17,719 --> 00:55:20,600
Speaker 1: getting a whole bunch of particles and getting them like

1128
00:55:20,760 --> 00:55:24,680
Speaker 1: in sync together into one quantum state, like a Bose

1129
00:55:24,719 --> 00:55:27,799
Speaker 1: Einstein condensate or something similar, where you can make like

1130
00:55:27,920 --> 00:55:32,400
Speaker 1: larger and larger objects that have quantum properties, and maybe

1131
00:55:32,400 --> 00:55:34,560
Speaker 1: we can make them large enough that we can start

1132
00:55:34,560 --> 00:55:38,880
Speaker 1: to see the gravitational effects between like clumps of quantum objects.

1133
00:55:39,600 --> 00:55:41,880
Speaker 3: I see, like if you make a big enough quantum object,

1134
00:55:41,920 --> 00:55:44,879
Speaker 3: you would see how anything quantum interacts with gravity. Because

1135
00:55:44,960 --> 00:55:48,000
Speaker 3: right now we don't really know, right like our theories

1136
00:55:48,040 --> 00:55:52,080
Speaker 3: break down when you try to make quantum particles interact

1137
00:55:52,080 --> 00:55:52,800
Speaker 3: with gravity.

1138
00:55:52,880 --> 00:55:55,520
Speaker 1: We just don't know what happens when quantum particles are

1139
00:55:55,560 --> 00:55:59,040
Speaker 1: feeling gravity. And so what we've done so far is

1140
00:55:59,160 --> 00:56:02,719
Speaker 1: made things like those Einstein condensates that have like you know,

1141
00:56:03,120 --> 00:56:06,320
Speaker 1: maybe up to a thousand atoms in them these tiny

1142
00:56:06,360 --> 00:56:09,279
Speaker 1: little blobs of stuff, and that's really not big enough

1143
00:56:09,320 --> 00:56:12,400
Speaker 1: to observe any gravity, because remember, gravity is the weakest

1144
00:56:12,440 --> 00:56:14,920
Speaker 1: force out there. But we're making progress, and it's the

1145
00:56:15,000 --> 00:56:17,359
Speaker 1: kind of thing where like in ten years undergrads will

1146
00:56:17,400 --> 00:56:19,719
Speaker 1: be doing that in their freshman physics lab. It'd be

1147
00:56:19,800 --> 00:56:22,000
Speaker 1: very easy, where it'd be like on a computer chip

1148
00:56:22,160 --> 00:56:25,440
Speaker 1: kind of thing, and in the basements of research facilities

1149
00:56:25,719 --> 00:56:29,200
Speaker 1: they'll be like having quantum diamonds in superpositions and doing

1150
00:56:29,239 --> 00:56:30,279
Speaker 1: crazy experiments.

1151
00:56:30,360 --> 00:56:32,000
Speaker 3: But I guess maybe the question is, you know, that

1152
00:56:32,080 --> 00:56:35,160
Speaker 3: might help us figure out if gravity's quantized, but how

1153
00:56:35,160 --> 00:56:38,400
Speaker 3: does that help us know if time is quantized or pixelated.

1154
00:56:38,560 --> 00:56:40,960
Speaker 1: Yeah, it'll tell us if gravity is a quantum theory

1155
00:56:41,080 --> 00:56:44,200
Speaker 1: or not, you know, or if space is quantized or not.

1156
00:56:44,239 --> 00:56:47,800
Speaker 1: So it will sort of help us get direction theoretically

1157
00:56:48,280 --> 00:56:50,719
Speaker 1: for how to tackle this very question about the nature

1158
00:56:50,760 --> 00:56:53,040
Speaker 1: of space and time. So it won't directly tell us

1159
00:56:53,080 --> 00:56:55,600
Speaker 1: if time is pixelated, it'll give us a lot of

1160
00:56:55,640 --> 00:56:58,600
Speaker 1: clues about how to build a theory of quantum gravity,

1161
00:56:58,640 --> 00:57:02,320
Speaker 1: and gravity of course very closely connected to space and time,

1162
00:57:02,640 --> 00:57:05,040
Speaker 1: so it'll sort of like help us lay the foundations

1163
00:57:05,080 --> 00:57:08,000
Speaker 1: to maybe eventually get there, but it's you know, it's

1164
00:57:08,120 --> 00:57:09,920
Speaker 1: nice to know that we might be able to do

1165
00:57:10,000 --> 00:57:13,360
Speaker 1: some experiments that can help us figure out if gravity

1166
00:57:13,440 --> 00:57:15,520
Speaker 1: is quantum or not, so that we can try to

1167
00:57:15,520 --> 00:57:17,959
Speaker 1: get our heads around these basic questions about the nature

1168
00:57:18,000 --> 00:57:18,800
Speaker 1: of space and time.

1169
00:57:19,080 --> 00:57:20,880
Speaker 3: Right, But even if you find out the gravity is

1170
00:57:20,920 --> 00:57:24,200
Speaker 3: quantized and space is quantized, you still wouldn't technically right.

1171
00:57:24,280 --> 00:57:27,760
Speaker 3: Maybe possibly now if time itself is also quantized. Like

1172
00:57:27,760 --> 00:57:29,280
Speaker 3: we said earlier, it could be the one of us

1173
00:57:29,320 --> 00:57:30,520
Speaker 3: quantized and the other one is not.

1174
00:57:31,040 --> 00:57:33,479
Speaker 1: But it depends on the details of your quantum theory. Right.

1175
00:57:33,720 --> 00:57:36,160
Speaker 1: So if you discover, for example, string theory is right,

1176
00:57:36,520 --> 00:57:39,400
Speaker 1: then string theory says, well, time is sort of continuous,

1177
00:57:39,440 --> 00:57:42,080
Speaker 1: but there is a minimum resolution below which it doesn't

1178
00:57:42,080 --> 00:57:44,640
Speaker 1: make sense to ask questions. Or if you discover, oh no,

1179
00:57:44,680 --> 00:57:47,640
Speaker 1: it looks like loop quantum gravity is correct and Carlo

1180
00:57:47,720 --> 00:57:50,680
Speaker 1: Rebellia is right and time is also quantized, so it

1181
00:57:50,760 --> 00:57:54,080
Speaker 1: might help you because it would reveal the quantum theory

1182
00:57:54,160 --> 00:57:57,560
Speaker 1: that describes space and time, which might require time to

1183
00:57:57,600 --> 00:58:00,480
Speaker 1: be continuous or smooth or am I show us that

1184
00:58:00,520 --> 00:58:03,040
Speaker 1: none of our ideas are correct and something else totally

1185
00:58:03,080 --> 00:58:06,080
Speaker 1: weird and new is required, and time might not be quantized.

1186
00:58:06,080 --> 00:58:08,160
Speaker 1: It might be something else totally different than we haven't

1187
00:58:08,200 --> 00:58:08,880
Speaker 1: even imagined.

1188
00:58:09,480 --> 00:58:10,560
Speaker 3: It might be a different time.

1189
00:58:11,440 --> 00:58:12,920
Speaker 1: It would be time for a new idea.

1190
00:58:13,080 --> 00:58:15,040
Speaker 3: It'll be a timely discovery.

1191
00:58:15,120 --> 00:58:17,040
Speaker 1: Yeah, so I would say that in summary, you know,

1192
00:58:17,080 --> 00:58:18,880
Speaker 1: it's not something that we're going to be able to

1193
00:58:18,920 --> 00:58:21,120
Speaker 1: directly probe very easily, but we can get around to

1194
00:58:21,160 --> 00:58:23,080
Speaker 1: it to sort of at the back by trying to

1195
00:58:23,120 --> 00:58:25,880
Speaker 1: build a consistent theory of space and time, which requires

1196
00:58:26,160 --> 00:58:27,480
Speaker 1: understanding quantum gravity.

1197
00:58:28,120 --> 00:58:30,240
Speaker 3: Because you don't think there is there could ever be

1198
00:58:30,280 --> 00:58:32,120
Speaker 3: an experiment that could test it directly.

1199
00:58:32,400 --> 00:58:37,280
Speaker 1: I think those experiments require such enormous energy. They're effectively

1200
00:58:37,320 --> 00:58:40,360
Speaker 1: like creating black holes, and so it's hard to imagine

1201
00:58:40,400 --> 00:58:43,120
Speaker 1: you ever doing experiments at that scale.

1202
00:58:43,080 --> 00:58:45,040
Speaker 3: Right, Who would ever make a black hole in purpose?

1203
00:58:46,240 --> 00:58:50,240
Speaker 1: I would, I totally would sign me up. I'm not

1204
00:58:50,240 --> 00:58:52,040
Speaker 1: saying I wouldn't want to. I'm just saying I don't

1205
00:58:52,040 --> 00:58:52,880
Speaker 1: think it's possible.

1206
00:58:53,080 --> 00:58:55,720
Speaker 3: I think maybe it's time to cut short this episode

1207
00:58:55,840 --> 00:58:58,520
Speaker 3: now before we introduce too many bad ideas into a

1208
00:58:58,560 --> 00:59:02,080
Speaker 3: physicist's brain. Well, I guess the question is yet to

1209
00:59:02,080 --> 00:59:04,040
Speaker 3: be the termins there are there are arguments for time

1210
00:59:04,080 --> 00:59:07,080
Speaker 3: being pixelated and arguments against time being pixelated. It sounds

1211
00:59:07,120 --> 00:59:09,680
Speaker 3: like we might never know. But if we make enough

1212
00:59:09,680 --> 00:59:13,720
Speaker 3: progress just in basic, you know, fundamental theories of the universe,

1213
00:59:13,760 --> 00:59:16,120
Speaker 3: maybe it'll come up. Hopefully it'll come up. Is that

1214
00:59:16,240 --> 00:59:19,160
Speaker 3: kind of the plan there, Let's focus on something else

1215
00:59:19,360 --> 00:59:22,840
Speaker 3: and let's procrastinate, and maybe it'll come up on its own.

1216
00:59:23,000 --> 00:59:25,720
Speaker 1: Let's figure out the foundations of everything, and maybe along

1217
00:59:25,760 --> 00:59:28,000
Speaker 1: the way we'll solve this other problem.

1218
00:59:28,160 --> 00:59:30,600
Speaker 3: All right, and maybe we'll find more time for you, Daniel,

1219
00:59:30,640 --> 00:59:32,560
Speaker 3: to do all the things you want to do. All right.

1220
00:59:32,600 --> 00:59:35,000
Speaker 3: Well again, I think it's an interesting reminder of how

1221
00:59:35,080 --> 00:59:37,320
Speaker 3: much we don't know about the universe, about basic things

1222
00:59:37,360 --> 00:59:38,960
Speaker 3: like space and time.

1223
00:59:38,920 --> 00:59:40,480
Speaker 1: And it's time that we figure them out.

1224
00:59:40,560 --> 00:59:43,600
Speaker 3: It's always a good time for physics, right, It's always

1225
00:59:43,600 --> 00:59:45,800
Speaker 3: a good time, and there's always a good time for.

1226
00:59:45,720 --> 00:59:48,160
Speaker 1: Physics, and physicists are always a good time.

1227
00:59:48,440 --> 00:59:51,640
Speaker 3: And that's but that's a theoretical conjecture there, Daniel.

1228
00:59:51,960 --> 00:59:53,320
Speaker 1: That's never been proven in the lab.

1229
00:59:53,840 --> 00:59:55,160
Speaker 3: No experiments have proven that.

1230
00:59:55,280 --> 00:59:58,920
Speaker 1: I think, unfortunately that's true. Maybe we should collide physicists

1231
00:59:58,920 --> 01:00:00,000
Speaker 1: together and just see what happens.

1232
01:00:00,480 --> 01:00:01,400
Speaker 3: Now that sounds like fun.

1233
01:00:01,600 --> 01:00:02,800
Speaker 1: That sounds like a good time to you.

1234
01:00:02,920 --> 01:00:05,320
Speaker 3: All right, Well, we hope you enjoyed that. Thanks for

1235
01:00:05,320 --> 01:00:07,240
Speaker 3: giving us your time. See you next time.

1236
01:00:15,040 --> 01:00:17,880
Speaker 1: Thanks for listening, and remember that. Daniel and Jorge Explain

1237
01:00:17,920 --> 01:00:21,919
Speaker 1: the Universe is a production of iHeartRadio. For more podcasts

1238
01:00:21,920 --> 01:00:26,560
Speaker 1: from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever

1239
01:00:26,640 --> 01:00:41,080
Speaker 1: you listen to your favorite shows. When you pop a

1240
01:00:41,080 --> 01:00:43,400
Speaker 1: piece of cheese into your mouth, you're probably not thinking

1241
01:00:43,440 --> 01:00:46,360
Speaker 1: about the environmental impact. But the people in the dairy

1242
01:00:46,360 --> 01:00:49,520
Speaker 1: industry are. That's why they're working hard every day to

1243
01:00:49,560 --> 01:00:52,600
Speaker 1: find new ways to reduce waste, conserve natural resources, and

1244
01:00:52,680 --> 01:00:56,560
Speaker 1: drive down greenhouse gas emissions. How is us dairy tackling

1245
01:00:56,600 --> 01:01:00,360
Speaker 1: greenhouse gases? Many farms use anaerobic digesters to turn the

1246
01:01:00,400 --> 01:01:04,800
Speaker 1: methane from maneure into renewable energy that can power farms, towns,

1247
01:01:04,800 --> 01:01:08,120
Speaker 1: and electric cars. Visit you as dairy dot COM's Last

1248
01:01:08,120 --> 01:01:09,720
Speaker 1: Sustainability to learn more.

1249
01:01:10,720 --> 01:01:14,280
Speaker 5: Hi, I'm David Eagleman from the podcast Inner Cosmos, which

1250
01:01:14,320 --> 01:01:16,160
Speaker 5: recently hit the number one science.

1251
01:01:15,920 --> 01:01:17,080
Speaker 2: Podcast in America.

1252
01:01:17,200 --> 01:01:20,280
Speaker 5: I mean neuroscientists at Stanford and I've spent my career

1253
01:01:20,400 --> 01:01:23,280
Speaker 5: exploring the three pound universe in our heads.

1254
01:01:23,640 --> 01:01:26,720
Speaker 2: Join me weekly to explore the relationship.

1255
01:01:26,040 --> 01:01:29,040
Speaker 5: Between your brain and your life, because the more we

1256
01:01:29,080 --> 01:01:31,800
Speaker 5: know about what's running under the hood, that or we

1257
01:01:31,800 --> 01:01:35,360
Speaker 5: can steer our lives. Listen to Inner Cosmos with David

1258
01:01:35,360 --> 01:01:38,880
Speaker 5: Eagleman on the iHeartRadio app, Apple Podcasts, or wherever you

1259
01:01:38,920 --> 01:01:40,000
Speaker 5: get your podcasts.

1260
01:01:40,600 --> 01:01:43,760
Speaker 14: I'm doctor Laurie Santos, host of the Happiness Lab podcast.

1261
01:01:44,200 --> 01:01:45,040
Speaker 7: As the US.

1262
01:01:44,800 --> 01:01:48,600
Speaker 14: Elections approach, you can feel like we're angrier and more

1263
01:01:48,600 --> 01:01:52,880
Speaker 14: divided than ever. But in a new hopeful season of

1264
01:01:52,960 --> 01:01:56,120
Speaker 14: my podcast, I'll Share with the Science Really shows it

1265
01:01:56,240 --> 01:01:58,919
Speaker 14: was surprisingly more united than most people think.

1266
01:01:59,160 --> 01:02:02,080
Speaker 13: We all know something is wrong in our culture, in

1267
01:02:02,120 --> 01:02:04,800
Speaker 13: our politics, and that we need to do better, and

1268
01:02:04,840 --> 01:02:05,880
Speaker 13: that we can do better.

1269
01:02:06,080 --> 01:02:09,880
Speaker 14: Listen on the iHeartRadio app, Apple Podcasts, or wherever you

1270
01:02:09,920 --> 01:02:11,000
Speaker 14: listen to podcasts.