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 --> 00:00:57,200
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
00:00:58,680 --> 00:01:01,480
Speaker 2: People are driven by the search for better, but when

20
00:01:01,480 --> 00:01:03,800
Speaker 2: it comes to hiring, the best way to search for

21
00:01:03,880 --> 00:01:07,760
Speaker 2: a candidate isn't to search at all. Don't search match

22
00:01:08,080 --> 00:01:11,640
Speaker 2: with Indeed. The hiring process can be slow and overwhelming.

23
00:01:12,000 --> 00:01:16,040
Speaker 2: Simplify hiring with Indeed. Indeed is your matching and hiring

24
00:01:16,120 --> 00:01:19,720
Speaker 2: platform with over three hundred and fifty million global monthly

25
00:01:19,840 --> 00:01:23,280
Speaker 2: visitors according to Indeed Data, and a matching engine that

26
00:01:23,360 --> 00:01:27,720
Speaker 2: helps you find quality candidates fast. Ditch the busy work.

27
00:01:28,080 --> 00:01:31,600
Speaker 2: Use Indeed for scheduling, screening, and messaging so you can

28
00:01:31,640 --> 00:01:35,160
Speaker 2: connect with candidates faster. Join more than three point five

29
00:01:35,240 --> 00:01:39,119
Speaker 2: million businesses worldwide that use Indeed to hire great talent.

30
00:01:39,319 --> 00:01:42,280
Speaker 2: Fast Listeners of this show will get a seventy five

31
00:01:42,400 --> 00:01:45,800
Speaker 2: dollars sponsored job credit to get your jobs more visibility

32
00:01:45,880 --> 00:01:51,480
Speaker 2: at indeed dot com slash po d katz twelve. That's

33
00:01:51,520 --> 00:01:57,800
Speaker 2: Indeed dot com slash pod katz twelve. Terms and conditions apply.

34
00:01:58,800 --> 00:02:02,240
Speaker 3: This is Michael wrapp Up and I've been professionally podcasting

35
00:02:02,360 --> 00:02:06,240
Speaker 3: for ten years. The podcast game has changed so much.

36
00:02:06,280 --> 00:02:08,960
Speaker 3: And if you're looking for the most disruptive podcast in

37
00:02:09,000 --> 00:02:12,920
Speaker 3: the world, that subscribe to the I Am Rapaport Stereo podcast.

38
00:02:13,080 --> 00:02:18,680
Speaker 3: Today we're talking sports, politics, pop culture, entertainment in anything

39
00:02:18,760 --> 00:02:22,800
Speaker 3: that catches my attention. Listen to the im Rapaport Stereo

40
00:02:22,960 --> 00:02:27,360
Speaker 3: podcast on the iHeartRadio app, Apple Podcasts, or wherever you

41
00:02:27,440 --> 00:02:28,519
Speaker 3: get your podcasts.

42
00:02:30,120 --> 00:02:32,120
Speaker 4: Hey, it's Horehand Daniel here and we want to tell

43
00:02:32,160 --> 00:02:33,280
Speaker 4: you about our new book.

44
00:02:33,400 --> 00:02:37,200
Speaker 1: It's called Frequently Asked Questions about the Universe.

45
00:02:36,880 --> 00:02:39,160
Speaker 4: Because you have questions about the universe, and so we

46
00:02:39,280 --> 00:02:41,160
Speaker 4: decided to write a book all about them.

47
00:02:41,240 --> 00:02:43,640
Speaker 1: We talk about your questions, we give some answers, we

48
00:02:43,720 --> 00:02:45,399
Speaker 1: make a bunch of silly jokes.

49
00:02:45,360 --> 00:02:48,120
Speaker 4: As usual, and we tackle all kinds of questions, including

50
00:02:48,200 --> 00:02:50,679
Speaker 4: what happens if I fall into a black hole? Or

51
00:02:50,840 --> 00:02:52,320
Speaker 4: is there another version of you out.

52
00:02:52,200 --> 00:02:55,959
Speaker 1: There that's right? Like usual, we tackle the deepest, darkest, biggest,

53
00:02:55,960 --> 00:02:58,720
Speaker 1: craziest questions about this incredible cosmos.

54
00:02:58,760 --> 00:03:00,600
Speaker 4: If you want to support the podcast, please get the

55
00:03:00,600 --> 00:03:02,680
Speaker 4: book and get a copy, not just for yourself, but

56
00:03:02,960 --> 00:03:08,480
Speaker 4: you know, for your nieces and nephews, cousins, friends, parents, dogs, hamsters.

57
00:03:08,200 --> 00:03:11,480
Speaker 1: And for the aliens. So get your copy of Frequently

58
00:03:11,560 --> 00:03:15,239
Speaker 1: Asked Questions about the Universe is available for pre order now,

59
00:03:15,360 --> 00:03:18,040
Speaker 1: coming out November two. You can find more details at

60
00:03:18,040 --> 00:03:23,200
Speaker 1: the book's website Universe faq dot com. Thanks for your support.

61
00:03:22,760 --> 00:03:24,720
Speaker 4: And if you have a hamster that can read, Please

62
00:03:24,800 --> 00:03:27,000
Speaker 4: let us know. We'd love to have them on the podcast.

63
00:03:37,440 --> 00:03:41,000
Speaker 4: Hey Daniel, I've noticed something pretty strange about how time works.

64
00:03:41,200 --> 00:03:43,360
Speaker 1: Oh yeah, did you have time to make your own

65
00:03:43,560 --> 00:03:44,400
Speaker 1: theory of time?

66
00:03:44,640 --> 00:03:46,960
Speaker 4: Well, that's the thing, right, Like, I noticed that time

67
00:03:47,120 --> 00:03:50,480
Speaker 4: seems to speed up as you get closer to a deadline.

68
00:03:50,520 --> 00:03:53,840
Speaker 1: That's true. Deadlines seem to be infinitely far in the future,

69
00:03:53,920 --> 00:03:55,880
Speaker 1: until all of a sudden they are on top of you.

70
00:03:56,280 --> 00:03:58,400
Speaker 4: Right. I think the only thing that can explain it

71
00:03:58,480 --> 00:04:02,400
Speaker 4: is that time itself all bends when it's closed to

72
00:04:02,480 --> 00:04:03,400
Speaker 4: some procrastination.

73
00:04:05,280 --> 00:04:08,120
Speaker 1: Well, time does slow down near a massive object, like

74
00:04:08,160 --> 00:04:08,720
Speaker 1: a black hole.

75
00:04:08,800 --> 00:04:12,400
Speaker 4: I think maybe I just need less massive deadlines maybe.

76
00:04:12,400 --> 00:04:14,720
Speaker 1: Or maybe your to do list is so dense it's

77
00:04:14,760 --> 00:04:16,000
Speaker 1: becoming a black hole.

78
00:04:16,279 --> 00:04:34,440
Speaker 4: Definitely sucks you in. Hi am Jorge. I'm a cartoonist

79
00:04:34,440 --> 00:04:36,000
Speaker 4: and the creator of PhD comics.

80
00:04:36,160 --> 00:04:38,960
Speaker 1: Hi I'm Daniel. I'm a particle physicist and a professor

81
00:04:39,080 --> 00:04:41,720
Speaker 1: you see Irvine, and I'm just part of Jorge's to

82
00:04:41,800 --> 00:04:42,200
Speaker 1: do list.

83
00:04:43,279 --> 00:04:46,080
Speaker 4: That sounds kind of inappropriate. Daniel, you mean I have

84
00:04:46,160 --> 00:04:49,520
Speaker 4: to be like Daniel, or I have to be Daniel.

85
00:04:49,600 --> 00:04:52,039
Speaker 1: I mean that I just contribute elements to your to

86
00:04:52,040 --> 00:04:52,440
Speaker 1: do list.

87
00:04:52,520 --> 00:04:54,200
Speaker 4: Oh, I see you add to my things to do.

88
00:04:54,839 --> 00:04:56,160
Speaker 1: I'm on your to do list.

89
00:04:57,400 --> 00:05:00,320
Speaker 4: But anyways, welcome to our podcast, Daniel and Jorge Explain

90
00:05:00,400 --> 00:05:03,160
Speaker 4: the Universe, a production of iHeartRadio.

91
00:05:02,640 --> 00:05:05,360
Speaker 1: In which our to do list is to explain the

92
00:05:05,520 --> 00:05:09,600
Speaker 1: entire universe bit by bit, concept by concept, puzzle by

93
00:05:09,680 --> 00:05:14,080
Speaker 1: puzzle to you, our wonderful listeners who deeply and desperately

94
00:05:14,120 --> 00:05:16,800
Speaker 1: want to understand the nature of the universe. We find

95
00:05:16,839 --> 00:05:20,640
Speaker 1: ourselves in the whole project of physics, starting with ancient

96
00:05:20,720 --> 00:05:22,800
Speaker 1: man looking up at the sky and extending to the

97
00:05:22,839 --> 00:05:25,920
Speaker 1: Greeks trying to understand the nature of reality, ends here

98
00:05:25,960 --> 00:05:29,039
Speaker 1: on the podcast when we try to break down the

99
00:05:29,160 --> 00:05:31,840
Speaker 1: nature of the universe and explain all of it to you.

100
00:05:32,240 --> 00:05:36,240
Speaker 4: And hopefully a timely matter, right, because you know, time

101
00:05:36,320 --> 00:05:39,960
Speaker 4: is money and money is gravity.

102
00:05:40,279 --> 00:05:42,000
Speaker 1: Money is dough and everybody needs it.

103
00:05:42,880 --> 00:05:45,440
Speaker 4: Yeah, sometimes we eat too much dough. But yeah, it

104
00:05:45,480 --> 00:05:47,480
Speaker 4: is a big, beautiful universe, and we like to talk

105
00:05:47,480 --> 00:05:51,360
Speaker 4: about all the things in it, even time itself, because

106
00:05:51,400 --> 00:05:53,160
Speaker 4: time is part of the universe. Right.

107
00:05:53,400 --> 00:05:56,039
Speaker 1: Time is part of the universe, though we don't understand

108
00:05:56,320 --> 00:05:58,400
Speaker 1: is it a fundamental element? Of the universe. Is it

109
00:05:58,480 --> 00:06:01,000
Speaker 1: something that bubbles up and just sort of appears from

110
00:06:01,000 --> 00:06:04,760
Speaker 1: other fundamental things like ice cream and lava and hurricanes,

111
00:06:05,120 --> 00:06:08,240
Speaker 1: or is it really deeply ingrained? And on this podcast,

112
00:06:08,240 --> 00:06:11,200
Speaker 1: we don't shy away from asking those really big, deep,

113
00:06:11,279 --> 00:06:14,840
Speaker 1: and difficult to grapple with questions, you know, like what

114
00:06:15,040 --> 00:06:17,479
Speaker 1: is time anyway? How do you even define it? How

115
00:06:17,520 --> 00:06:21,080
Speaker 1: do you even ask crisp and precise questions about this

116
00:06:21,320 --> 00:06:23,920
Speaker 1: slipperiest but most essential of concepts.

117
00:06:24,040 --> 00:06:26,600
Speaker 4: Yeah, because time but always seems to slip by you

118
00:06:26,800 --> 00:06:30,160
Speaker 4: no matter what do you do. And asking these questions

119
00:06:30,200 --> 00:06:31,680
Speaker 4: is not just in our to do list, but it's

120
00:06:31,680 --> 00:06:33,839
Speaker 4: also in our want to do list, right, you know.

121
00:06:34,320 --> 00:06:35,839
Speaker 4: I mean that's kind of what you're getting paid for.

122
00:06:36,040 --> 00:06:37,440
Speaker 1: That is what I get paid for. Not on a

123
00:06:37,520 --> 00:06:40,400
Speaker 1: day to day basis. I mostly am cracking open particles

124
00:06:40,440 --> 00:06:43,080
Speaker 1: at the Large Hadron Collider, But these are the big

125
00:06:43,120 --> 00:06:47,360
Speaker 1: goals of physics, is to understand the nature of our experience.

126
00:06:47,680 --> 00:06:49,479
Speaker 1: You know, some people think physics is sort of like

127
00:06:49,760 --> 00:06:52,880
Speaker 1: abstract and separated from humanity. But it's taken me a

128
00:06:52,880 --> 00:06:55,120
Speaker 1: long time to realize that it's the most human of

129
00:06:55,200 --> 00:06:57,719
Speaker 1: sciences because it asks these questions at the very core

130
00:06:58,040 --> 00:07:00,000
Speaker 1: of the context of what it's like to be a lie.

131
00:07:00,800 --> 00:07:03,800
Speaker 1: You know, you notice things slipping into the past through

132
00:07:03,839 --> 00:07:08,080
Speaker 1: this weird instantaneous slice called the present. It's definitely something

133
00:07:08,120 --> 00:07:09,160
Speaker 1: we'd like to understand.

134
00:07:09,200 --> 00:07:13,320
Speaker 4: Are you saying physics out humanities to humanities? Daniel? You

135
00:07:13,400 --> 00:07:15,080
Speaker 4: out philosophize the philosophers.

136
00:07:15,920 --> 00:07:16,160
Speaker 5: Yeah.

137
00:07:16,240 --> 00:07:18,360
Speaker 1: You know, I used to think that physics was the

138
00:07:18,360 --> 00:07:21,320
Speaker 1: most interesting science because it was probably the most fundamental,

139
00:07:21,320 --> 00:07:24,240
Speaker 1: the most universal, that somehow it escaped humanity, that if

140
00:07:24,280 --> 00:07:28,040
Speaker 1: aliens came, they wouldn't be interested in our biological advances

141
00:07:28,080 --> 00:07:30,160
Speaker 1: because they wouldn't be relevant to them, but they would

142
00:07:30,200 --> 00:07:32,600
Speaker 1: be interested in what we've learned about physics. I'm not

143
00:07:32,640 --> 00:07:33,840
Speaker 1: so sure about that anymore.

144
00:07:33,880 --> 00:07:36,080
Speaker 4: And can hear all those mathematicians out there laughing at

145
00:07:36,120 --> 00:07:39,320
Speaker 4: you right now? You're like, you're pure, We're the.

146
00:07:39,280 --> 00:07:43,920
Speaker 1: Purest, even mathematicians. Man, Mathematics is just codification of the

147
00:07:43,960 --> 00:07:47,280
Speaker 1: logic and human brains. And I suspect that aliens might

148
00:07:47,320 --> 00:07:49,200
Speaker 1: not even do math, and if they do, we might

149
00:07:49,240 --> 00:07:50,600
Speaker 1: not even recognize it.

150
00:07:50,760 --> 00:07:54,679
Speaker 4: Oh man, you're saying physics supersedes math from a human

151
00:07:54,720 --> 00:07:58,040
Speaker 4: point of view. Oh boy, we just started an academic warrior.

152
00:07:58,440 --> 00:08:00,360
Speaker 1: You just did that. That's not what I'm saying at all.

153
00:08:00,400 --> 00:08:02,600
Speaker 1: I'm saying that everything we do is based in human

154
00:08:02,600 --> 00:08:06,080
Speaker 1: thought and contextualized by human questions. But that doesn't make

155
00:08:06,120 --> 00:08:08,679
Speaker 1: it worthless. It means that we get to ask really

156
00:08:08,720 --> 00:08:11,040
Speaker 1: interesting questions about what it's like to be alive.

157
00:08:11,400 --> 00:08:14,280
Speaker 4: Yeah, And so sometimes those questions get into the idea

158
00:08:14,280 --> 00:08:17,440
Speaker 4: of time itself, because I think maybe most people have

159
00:08:17,480 --> 00:08:20,600
Speaker 4: a conception of the universe it's sort of existing outside

160
00:08:20,600 --> 00:08:23,520
Speaker 4: of time, or like it's a universe moving through time.

161
00:08:23,760 --> 00:08:27,640
Speaker 4: But actually physicists think of time as part of the universe, right,

162
00:08:27,680 --> 00:08:29,080
Speaker 4: it's like another thing in it.

163
00:08:29,240 --> 00:08:32,360
Speaker 1: Yeah, we don't really understand. Physicists like to divide elements

164
00:08:32,360 --> 00:08:35,520
Speaker 1: of the universe into things that are fundamental, meaning they're

165
00:08:35,559 --> 00:08:39,120
Speaker 1: like basic, they're essential, they have to be there. They

166
00:08:39,160 --> 00:08:41,920
Speaker 1: define what the universe is, and then other things that

167
00:08:42,000 --> 00:08:44,280
Speaker 1: are emergent that sort of come out of the interplay

168
00:08:44,280 --> 00:08:47,560
Speaker 1: of those fundamental objects. And we don't know if time

169
00:08:47,800 --> 00:08:51,120
Speaker 1: is fundamental, if it's like absolutely essential it's part of

170
00:08:51,160 --> 00:08:53,920
Speaker 1: the nature of the universe, or if it bubbles up

171
00:08:53,960 --> 00:08:56,800
Speaker 1: from something else. We don't know if space and matter

172
00:08:56,880 --> 00:08:59,360
Speaker 1: sort of sit in a framework of time which is

173
00:08:59,360 --> 00:09:01,960
Speaker 1: external to them, or if the whole thing is just

174
00:09:02,040 --> 00:09:05,080
Speaker 1: you know, comes up from some other weird, deep nature

175
00:09:05,120 --> 00:09:06,880
Speaker 1: we haven't even imagined.

176
00:09:06,559 --> 00:09:09,840
Speaker 4: Like is it hard coded into the circuitry of the universe,

177
00:09:10,000 --> 00:09:11,880
Speaker 4: or is it like a program running on top of

178
00:09:11,920 --> 00:09:14,840
Speaker 4: the chip of the universe that's kind of what you mean, right.

179
00:09:14,760 --> 00:09:17,600
Speaker 1: Mm hmm. Or is it just the way the humans think,

180
00:09:17,880 --> 00:09:20,320
Speaker 1: you know, It might be that our tendency to think

181
00:09:20,360 --> 00:09:24,679
Speaker 1: in terms of stories and narratives which have cause and effect,

182
00:09:25,120 --> 00:09:29,120
Speaker 1: might bias us to see things as flowing forwards in time,

183
00:09:29,200 --> 00:09:32,119
Speaker 1: when in reality the truth might be much more complex.

184
00:09:32,440 --> 00:09:35,440
Speaker 1: We just in an episode about how causality, cause and

185
00:09:35,440 --> 00:09:39,160
Speaker 1: effect might not even be an essential element of the universe,

186
00:09:39,559 --> 00:09:42,040
Speaker 1: and so it might be that time itself could be

187
00:09:42,120 --> 00:09:43,920
Speaker 1: something that's just sort of very human.

188
00:09:44,160 --> 00:09:46,800
Speaker 4: Yeah, it's sort of like this podcast. We have no narrative, right,

189
00:09:47,200 --> 00:09:50,840
Speaker 4: We are just jumping around in time to whatever comes

190
00:09:50,880 --> 00:09:52,120
Speaker 4: into our minds here.

191
00:09:52,240 --> 00:09:54,360
Speaker 1: But it is these kind of basic questions that give

192
00:09:54,440 --> 00:09:57,440
Speaker 1: us a launching off point for asking questions and doing

193
00:09:57,520 --> 00:10:00,960
Speaker 1: studies and trying to like find way to grapple with

194
00:10:01,000 --> 00:10:03,800
Speaker 1: these things scientifically. Because we could sit here and smoke

195
00:10:03,880 --> 00:10:06,640
Speaker 1: banana peels and talk about the nature of time forever

196
00:10:06,920 --> 00:10:09,640
Speaker 1: without making progress. But we want to do experiments. We

197
00:10:09,679 --> 00:10:12,200
Speaker 1: want to use science to add to our body of

198
00:10:12,440 --> 00:10:14,000
Speaker 1: actual knowledge about time.

199
00:10:14,280 --> 00:10:17,400
Speaker 4: Yeah, so we'll be exploring a little bit about this

200
00:10:17,559 --> 00:10:22,199
Speaker 4: weird concept of time and especially about how time behaves

201
00:10:22,240 --> 00:10:25,720
Speaker 4: according to our theories about the universe. So today on

202
00:10:25,760 --> 00:10:33,760
Speaker 4: the podcast, we'll be asking the question why does gravity

203
00:10:34,120 --> 00:10:37,960
Speaker 4: slow down time? Or should I should I ask it

204
00:10:38,040 --> 00:10:39,920
Speaker 4: slow down time?

205
00:10:40,920 --> 00:10:43,480
Speaker 1: Or maybe you should use your gravest voice, you know,

206
00:10:43,559 --> 00:10:45,120
Speaker 1: your James Earl Jones voice.

207
00:10:45,480 --> 00:10:47,800
Speaker 4: You're trying to make a gravity joke. That's kind of heavy, man,

208
00:10:48,080 --> 00:10:49,400
Speaker 4: don't make light of the situation.

209
00:10:49,640 --> 00:10:51,240
Speaker 1: I'm a massive fan of that movie.

210
00:10:51,280 --> 00:10:51,480
Speaker 6: You know.

211
00:10:51,720 --> 00:10:53,760
Speaker 4: Now, this question kind of has two components to it,

212
00:10:53,800 --> 00:10:56,360
Speaker 4: Like you just said, it has gravity and time in it.

213
00:10:56,480 --> 00:10:59,520
Speaker 4: And because we know from physics that somehow gravity affects

214
00:10:59,559 --> 00:11:03,360
Speaker 4: time or related to time, because in the time can

215
00:11:03,400 --> 00:11:06,360
Speaker 4: be affected. It's not like some sort of absolute thing.

216
00:11:06,559 --> 00:11:08,680
Speaker 1: That's right, and we do not have like a single

217
00:11:08,760 --> 00:11:11,720
Speaker 1: clock for the universe. The simplest model of how time

218
00:11:11,800 --> 00:11:14,960
Speaker 1: works might be imagining that the universe all over the

219
00:11:14,960 --> 00:11:17,440
Speaker 1: place is in one state. You know, particles are going

220
00:11:17,440 --> 00:11:19,839
Speaker 1: in some direction or they're in some location, and then

221
00:11:19,880 --> 00:11:22,360
Speaker 1: things sort of tick forwards and everything takes a step

222
00:11:22,400 --> 00:11:25,600
Speaker 1: forward in unison, and in that picture, the whole universe

223
00:11:25,640 --> 00:11:28,280
Speaker 1: has like a single clock. But we've learned over the

224
00:11:28,360 --> 00:11:30,840
Speaker 1: last one hundred years that that conception of time is

225
00:11:30,880 --> 00:11:33,480
Speaker 1: not valid. The time flows differently in different parts of

226
00:11:33,520 --> 00:11:37,120
Speaker 1: the universe, and differently four different observers are moving at

227
00:11:37,160 --> 00:11:41,320
Speaker 1: different speeds. So time is much weirder, more local, and

228
00:11:41,440 --> 00:11:45,160
Speaker 1: less universal than we ever imagined. In addition, it's also

229
00:11:45,600 --> 00:11:47,920
Speaker 1: weirdly bent by heavy objects.

230
00:11:48,160 --> 00:11:50,880
Speaker 4: Yeah, things that are really heavy, like black holes or

231
00:11:50,960 --> 00:11:55,320
Speaker 4: even just our planet, they have gravity, and that somehow

232
00:11:55,480 --> 00:11:59,160
Speaker 4: makes time slow down. Now that's a pretty weird concept.

233
00:11:59,200 --> 00:12:01,400
Speaker 4: Bred I guess that was in that movie Interstellar.

234
00:12:01,559 --> 00:12:03,800
Speaker 1: It was exactly in that movie Interstellar. Every time they

235
00:12:03,920 --> 00:12:07,240
Speaker 1: visited a really heavy planet or came near a black hole.

236
00:12:07,559 --> 00:12:09,440
Speaker 1: When they left, they found that the rest of the

237
00:12:09,520 --> 00:12:12,240
Speaker 1: universe had experienced a lot more time than they had.

238
00:12:12,280 --> 00:12:13,559
Speaker 4: And so I think a lot of people are maybe

239
00:12:13,640 --> 00:12:16,880
Speaker 4: familiar with this part of relativity, where like, if you're

240
00:12:16,920 --> 00:12:19,800
Speaker 4: moving fast, time slows down. But also it also happens

241
00:12:19,840 --> 00:12:21,640
Speaker 4: when you're near a heavy object.

242
00:12:21,760 --> 00:12:24,280
Speaker 1: That's right. These are two completely separate effects, with different

243
00:12:24,320 --> 00:12:28,160
Speaker 1: sources and importantly different mechanisms and different consequences.

244
00:12:28,320 --> 00:12:30,520
Speaker 4: Yeah. So, as usually, we were wondering how many people

245
00:12:30,559 --> 00:12:33,800
Speaker 4: out there even it knew that gravity slowed down time

246
00:12:34,520 --> 00:12:37,280
Speaker 4: or much less I have thought about why it slows

247
00:12:37,320 --> 00:12:40,199
Speaker 4: down time. So Daniel went out there into the internet

248
00:12:40,200 --> 00:12:42,880
Speaker 4: to ask people why does gravity slow down time?

249
00:12:42,960 --> 00:12:44,560
Speaker 1: I like the way you say I went out there

250
00:12:44,600 --> 00:12:46,320
Speaker 1: into the Internet. It makes me feel like I got

251
00:12:46,360 --> 00:12:49,200
Speaker 1: sucked into my computer and went and like visited.

252
00:12:48,880 --> 00:12:53,720
Speaker 4: These people like tron like eighties movie plotline, and you got,

253
00:12:53,960 --> 00:12:56,480
Speaker 4: you know, sucked into your CRT monitor.

254
00:12:56,600 --> 00:12:56,800
Speaker 2: Yeah.

255
00:12:56,800 --> 00:12:59,599
Speaker 1: I'm writing those tron cycles around the Internet, gathering in

256
00:12:59,679 --> 00:13:00,640
Speaker 1: front of from our.

257
00:13:00,600 --> 00:13:03,920
Speaker 4: Listitors, dodging trolls, and tweeting left and right.

258
00:13:04,160 --> 00:13:06,240
Speaker 1: But if you out there would like me to beam

259
00:13:06,280 --> 00:13:09,920
Speaker 1: myself into your inbox with crazy questions about the nature

260
00:13:10,000 --> 00:13:12,760
Speaker 1: of the universe so you can hear yourself speculate about

261
00:13:12,760 --> 00:13:15,720
Speaker 1: them on the podcast, please don't be shy. Write to

262
00:13:15,760 --> 00:13:18,559
Speaker 1: me to questions at Danielandjorge dot com.

263
00:13:18,640 --> 00:13:20,920
Speaker 4: Yeah, and you actually answer every email, right.

264
00:13:21,000 --> 00:13:24,320
Speaker 1: I do answer every email with every question from everybody.

265
00:13:24,440 --> 00:13:25,240
Speaker 4: You take the time.

266
00:13:26,000 --> 00:13:27,840
Speaker 1: It slows me down, but I love it all right.

267
00:13:27,880 --> 00:13:29,440
Speaker 4: Well, here's what people had to say.

268
00:13:29,640 --> 00:13:38,400
Speaker 7: Well, gravity is basically the same as acceleration, and when

269
00:13:38,440 --> 00:13:44,240
Speaker 7: you're accelerating, the speed of light stays the same for everybody,

270
00:13:44,280 --> 00:13:48,200
Speaker 7: and so it must be time that's slowing down. Yeah,

271
00:13:48,240 --> 00:13:50,960
Speaker 7: and when we're going at our normal speeds, you don't

272
00:13:51,000 --> 00:13:58,040
Speaker 7: really notice it. So gravity being equivalent to acceleration causes

273
00:13:58,080 --> 00:13:58,840
Speaker 7: the same effect.

274
00:13:59,200 --> 00:14:02,559
Speaker 8: Gravity slows down time because as particles with mass move

275
00:14:02,600 --> 00:14:05,120
Speaker 8: through the Higgs field, they're so down. The stronger the

276
00:14:05,200 --> 00:14:07,480
Speaker 8: Higgs field, the gravity is the sore of the quarks

277
00:14:07,480 --> 00:14:10,720
Speaker 8: and Lepton's move causing quantum interactions to take place at

278
00:14:10,720 --> 00:14:12,920
Speaker 8: a different rate depending on the strength of the field.

279
00:14:13,480 --> 00:14:15,960
Speaker 8: Scaled up into the macro world, that's what we experienced

280
00:14:16,000 --> 00:14:18,280
Speaker 8: as time. We would never notice if our particles were

281
00:14:18,320 --> 00:14:21,000
Speaker 8: moving at a faster sore speed, if everything we observed

282
00:14:21,080 --> 00:14:23,400
Speaker 8: was experiencing the same Higgs field along with us.

283
00:14:23,600 --> 00:14:26,960
Speaker 6: I guess that the reason if because the gravity bends

284
00:14:26,960 --> 00:14:31,520
Speaker 6: down with pafe time, and I think the length of

285
00:14:31,720 --> 00:14:34,320
Speaker 6: faith change if in order for the speed of light

286
00:14:34,400 --> 00:14:38,400
Speaker 6: were being constant, was the time of flowing a different ways.

287
00:14:39,000 --> 00:14:44,040
Speaker 9: First of all, time is a like space dimension, So

288
00:14:44,640 --> 00:14:47,920
Speaker 9: the gravity can affect time.

289
00:14:48,600 --> 00:14:52,840
Speaker 1: But how I'm thinking right now, like the.

290
00:14:52,800 --> 00:15:00,120
Speaker 9: Gravity does to also the objects then contracts them. And

291
00:15:00,000 --> 00:15:03,040
Speaker 9: and this is what I'm thinking, that it contracts time.

292
00:15:03,840 --> 00:15:09,040
Speaker 9: It squeezes it like the space and doing this, it's

293
00:15:09,080 --> 00:15:10,000
Speaker 9: slowing it down.

294
00:15:10,400 --> 00:15:14,640
Speaker 10: I guess gravity could slow down time because gravity makes

295
00:15:14,680 --> 00:15:20,040
Speaker 10: those wells in like the space time fabric, and so

296
00:15:20,720 --> 00:15:25,320
Speaker 10: as that material of the universe gets stretched out, the

297
00:15:25,360 --> 00:15:30,440
Speaker 10: time would slow down as it gets deeper, sort of

298
00:15:31,080 --> 00:15:34,880
Speaker 10: like if you're driving over hills versus driving over flat things.

299
00:15:35,320 --> 00:15:38,400
Speaker 11: I can only imagine it's got something to do with

300
00:15:39,320 --> 00:15:44,480
Speaker 11: space time. Like gravity isn't just a force, but as

301
00:15:44,520 --> 00:15:51,160
Speaker 11: Einstein says, it's a warping of space time. And if

302
00:15:51,160 --> 00:15:53,200
Speaker 11: you've got a ton of gravity, say in a black hole,

303
00:15:53,240 --> 00:15:56,800
Speaker 11: warping space space is not really a thing, but space

304
00:15:56,840 --> 00:15:59,840
Speaker 11: time is a thing. So you can't affect one without

305
00:15:59,840 --> 00:16:03,400
Speaker 11: acting the other, is what I'm guessing.

306
00:16:04,160 --> 00:16:08,160
Speaker 12: I know time moves slower relatively speaking for someone that

307
00:16:08,320 --> 00:16:13,040
Speaker 12: travels faster, So maybe gravity slows down time because it

308
00:16:13,280 --> 00:16:18,160
Speaker 12: also necessarily makes an object or person move faster.

309
00:16:18,480 --> 00:16:21,120
Speaker 4: All Right, some pretty good answers here. A lot of

310
00:16:21,120 --> 00:16:24,760
Speaker 4: people sort of knew that time can slow down, and

311
00:16:24,960 --> 00:16:27,720
Speaker 4: I guess they assume that gravity is somewhat related to

312
00:16:28,560 --> 00:16:31,080
Speaker 4: relativity and moving fast, and so why not.

313
00:16:31,320 --> 00:16:33,880
Speaker 1: Yeah, a lot of really interesting and insightful and thoughtful

314
00:16:33,920 --> 00:16:36,480
Speaker 1: questions here, some confusion about the role of the Higgs field,

315
00:16:36,600 --> 00:16:39,200
Speaker 1: but also a lot of good concepts about the connections

316
00:16:39,240 --> 00:16:41,920
Speaker 1: between space and time and how masses have to bend

317
00:16:42,040 --> 00:16:42,560
Speaker 1: both of them.

318
00:16:42,720 --> 00:16:42,800
Speaker 13: All.

319
00:16:42,920 --> 00:16:46,320
Speaker 4: Right, well, let's get into this idea of time slowing down,

320
00:16:46,520 --> 00:16:48,840
Speaker 4: and I guess let's recap maybe the one people are

321
00:16:48,880 --> 00:16:51,080
Speaker 4: most familiar with, maybe, which is the one that when

322
00:16:51,120 --> 00:16:53,840
Speaker 4: you're moving fast and especially close to the speed of light,

323
00:16:54,080 --> 00:16:57,600
Speaker 4: time slows down for you. So maybe walk us through that,

324
00:16:57,640 --> 00:16:59,560
Speaker 4: and then we'll get into the one about gravitation.

325
00:17:00,120 --> 00:17:02,160
Speaker 1: Right, So, the one you're probably more familiar with, we

326
00:17:02,240 --> 00:17:05,919
Speaker 1: call velocity time dilation. This is something that happens in

327
00:17:05,960 --> 00:17:08,879
Speaker 1: special relativity. And to think about this, you should imagine

328
00:17:08,920 --> 00:17:12,720
Speaker 1: an empty universe, one without really massive objects that are

329
00:17:12,760 --> 00:17:15,320
Speaker 1: going to make space curvy and all sorts of weird stuff.

330
00:17:15,359 --> 00:17:19,240
Speaker 1: In this universe, light travels in straight lines, and spaceships

331
00:17:19,359 --> 00:17:22,840
Speaker 1: zoom around, and all the time dilation just comes from

332
00:17:22,960 --> 00:17:27,160
Speaker 1: the relative velocity of objects. And the most important thing

333
00:17:27,200 --> 00:17:31,439
Speaker 1: to remember is that moving clocks run slowly. So people

334
00:17:31,520 --> 00:17:34,320
Speaker 1: often make the mistake of saying, oh, I'm going fast

335
00:17:34,359 --> 00:17:37,600
Speaker 1: in a spaceship, so my time should slow down, right, Well,

336
00:17:37,640 --> 00:17:40,080
Speaker 1: it's only moving clocks that slow down. So if you're

337
00:17:40,080 --> 00:17:42,639
Speaker 1: in a spaceship and you're holding the clock, then the

338
00:17:42,640 --> 00:17:45,679
Speaker 1: clock's not moving relative to you, so you're not going

339
00:17:45,760 --> 00:17:49,040
Speaker 1: to see it slow down. So you never experience velocity

340
00:17:49,080 --> 00:17:52,120
Speaker 1: time dilation because you're never moving a relative to yourself.

341
00:17:52,520 --> 00:17:55,240
Speaker 1: Somebody else out there on a planet that you're zipping

342
00:17:55,320 --> 00:17:58,960
Speaker 1: by could see your clock running slowly because your clock

343
00:17:59,200 --> 00:18:02,159
Speaker 1: is moving for them, and so moving clocks run slowly,

344
00:18:02,400 --> 00:18:05,639
Speaker 1: meaning that your clock would run slow. You don't experience it,

345
00:18:05,840 --> 00:18:08,640
Speaker 1: but they see your clock moving slowly.

346
00:18:08,359 --> 00:18:10,840
Speaker 4: Right, Like, if your time is moving slowly, you don't

347
00:18:10,840 --> 00:18:14,520
Speaker 4: notice it because you know your brain is also sort

348
00:18:14,560 --> 00:18:16,800
Speaker 4: of moving slowly in a way, right, So, like everything

349
00:18:16,800 --> 00:18:19,159
Speaker 4: about you is moving slowly as well, and so you

350
00:18:19,520 --> 00:18:21,360
Speaker 4: don't notice that you're actually moving slowly.

351
00:18:21,400 --> 00:18:23,760
Speaker 1: But even that suggests there's some sort of like universal

352
00:18:23,800 --> 00:18:26,919
Speaker 1: picture of what really happened, and in that universal picture,

353
00:18:27,119 --> 00:18:29,840
Speaker 1: it makes sense for you to feel like time move normally,

354
00:18:29,960 --> 00:18:32,439
Speaker 1: even though it actually moves slowly. But there is no

355
00:18:32,640 --> 00:18:36,320
Speaker 1: like what actually happened. Some observers seeing you go by

356
00:18:36,359 --> 00:18:38,840
Speaker 1: the planet at ninety five percent of the speed of light,

357
00:18:38,960 --> 00:18:42,080
Speaker 1: they see your time as moving slowly. You see your

358
00:18:42,119 --> 00:18:45,120
Speaker 1: time as moving normally. You can try to unify those

359
00:18:45,160 --> 00:18:47,520
Speaker 1: into one picture of what actually happened, But there is

360
00:18:47,560 --> 00:18:51,680
Speaker 1: no what actually happened. There's just what different observers observe,

361
00:18:52,080 --> 00:18:54,239
Speaker 1: and what you see depends on where you are and

362
00:18:54,280 --> 00:18:58,160
Speaker 1: how fast things are moving relative to you. For example,

363
00:18:58,240 --> 00:18:59,720
Speaker 1: if you're on the spaceship and you're looking at the

364
00:18:59,760 --> 00:19:02,760
Speaker 1: clock on Earth, you see Earth moving past you at

365
00:19:02,840 --> 00:19:05,840
Speaker 1: high speed, and so you see earth clock running slowly.

366
00:19:06,200 --> 00:19:09,040
Speaker 1: So Earth sees your clock running slow. You see Earth

367
00:19:09,119 --> 00:19:12,840
Speaker 1: clock running slow. What actually happened, Well, both of those

368
00:19:12,880 --> 00:19:15,920
Speaker 1: things happened. Is just what happened depends on where you are.

369
00:19:16,080 --> 00:19:18,000
Speaker 4: I guess maybe stem me through it. So I'm here

370
00:19:18,040 --> 00:19:20,360
Speaker 4: on Earth, I'm watching you on a spaceship go by

371
00:19:20,440 --> 00:19:23,000
Speaker 4: at ninety five percent of the speed of light, Like,

372
00:19:23,040 --> 00:19:24,760
Speaker 4: what does it mean for me to see your time

373
00:19:24,800 --> 00:19:27,399
Speaker 4: slow down? Like? I see your the clock inside of

374
00:19:27,440 --> 00:19:30,400
Speaker 4: your spaceship ticking, but it's not ticking as fast as

375
00:19:30,440 --> 00:19:31,560
Speaker 4: my clock exactly.

376
00:19:31,920 --> 00:19:34,439
Speaker 1: So you get a telescope and it's super powerful. So

377
00:19:34,520 --> 00:19:37,119
Speaker 1: you can look at a clock that's inside my ship

378
00:19:37,280 --> 00:19:39,680
Speaker 1: and you watch it and you see its ticks going,

379
00:19:39,720 --> 00:19:41,720
Speaker 1: and you compare it to a clock that's right in

380
00:19:41,840 --> 00:19:44,800
Speaker 1: your hand, not moving relative to you. And so every

381
00:19:44,840 --> 00:19:47,679
Speaker 1: time my clock ticks on the spaceship, you see the

382
00:19:47,680 --> 00:19:50,320
Speaker 1: clock in your lap ticking ten times. So time is

383
00:19:50,359 --> 00:19:52,840
Speaker 1: moving faster for you in your lap. Then you see

384
00:19:52,880 --> 00:19:55,000
Speaker 1: it moving for me on the ship. And this, of

385
00:19:55,000 --> 00:19:57,280
Speaker 1: course already takes some an account the fact that it

386
00:19:57,359 --> 00:20:00,240
Speaker 1: takes light time to get to you, to the telescop

387
00:20:00,440 --> 00:20:02,680
Speaker 1: from the ship. We sort of factor that out already.

388
00:20:02,840 --> 00:20:04,359
Speaker 4: So what does it mean? So I have a telescope

389
00:20:04,400 --> 00:20:07,400
Speaker 4: and I'm pointing it at you, but you're zooming by,

390
00:20:07,440 --> 00:20:08,960
Speaker 4: so I have to kind of track you. I have

391
00:20:09,000 --> 00:20:12,000
Speaker 4: to move my telescope, and so I track you as

392
00:20:12,040 --> 00:20:14,160
Speaker 4: you're going by, and I'm moving my telescope and I'm

393
00:20:14,200 --> 00:20:17,840
Speaker 4: measuring your ticks and they're not taking as fast as

394
00:20:17,880 --> 00:20:18,280
Speaker 4: my clock.

395
00:20:18,400 --> 00:20:21,439
Speaker 1: That's right. You see my clock as running slowly, So

396
00:20:21,520 --> 00:20:24,560
Speaker 1: you see me aging slowly, You see me moving slowly.

397
00:20:24,600 --> 00:20:27,240
Speaker 1: You see me like waving back to you in super

398
00:20:27,280 --> 00:20:30,560
Speaker 1: slow motion, so you see my clock as running slow

399
00:20:30,840 --> 00:20:31,880
Speaker 1: relative to your.

400
00:20:31,720 --> 00:20:34,399
Speaker 4: Clock, and that's the sort of a consequence of just

401
00:20:34,440 --> 00:20:37,600
Speaker 4: how the universe is or to the somehow the limitations

402
00:20:37,640 --> 00:20:38,440
Speaker 4: of the speed of light.

403
00:20:38,600 --> 00:20:41,040
Speaker 1: Yeah, it's really interesting. You can start from lots of

404
00:20:41,040 --> 00:20:43,439
Speaker 1: different places to derive this. You can say like, well,

405
00:20:43,480 --> 00:20:46,160
Speaker 1: we've seen that nothing can move faster than the speed

406
00:20:46,200 --> 00:20:48,960
Speaker 1: of light. That's a hard limit on the speed of information.

407
00:20:49,400 --> 00:20:52,080
Speaker 1: And from that you can derive these things, these time

408
00:20:52,160 --> 00:20:54,840
Speaker 1: dilation effects, and you can walk yourself through an example.

409
00:20:54,920 --> 00:20:56,879
Speaker 1: We actually have it worked out in detail in our

410
00:20:56,880 --> 00:21:00,320
Speaker 1: book We have No Idea, a Guide to the Unknown Universe.

411
00:21:00,560 --> 00:21:03,560
Speaker 1: And you can think about how a photon clock would

412
00:21:03,640 --> 00:21:06,040
Speaker 1: tick in a spaceship as it moves up and down,

413
00:21:06,280 --> 00:21:07,919
Speaker 1: and if it's moving really fast, and it has to

414
00:21:07,960 --> 00:21:11,240
Speaker 1: go like a little bit diagonal for example, and because

415
00:21:11,359 --> 00:21:14,240
Speaker 1: light can't move faster than the speed of light, when

416
00:21:14,240 --> 00:21:16,400
Speaker 1: it moves on a diagonal, it takes longer to get

417
00:21:16,440 --> 00:21:18,760
Speaker 1: from one side of the clock to the other. So

418
00:21:18,920 --> 00:21:21,639
Speaker 1: it's basically the constancy of the speed of light and

419
00:21:21,640 --> 00:21:24,119
Speaker 1: the fact that nothing, even light can move faster than

420
00:21:24,160 --> 00:21:26,879
Speaker 1: the speed of light. Directly lead to this consequence, the

421
00:21:26,960 --> 00:21:28,840
Speaker 1: time goes slower for moving.

422
00:21:28,520 --> 00:21:31,879
Speaker 4: Clocks, right, And so there's this sort of famous scenario

423
00:21:32,000 --> 00:21:35,000
Speaker 4: called the twin paradox or the twin experiment, where like

424
00:21:35,200 --> 00:21:37,119
Speaker 4: you take a pair of twins here on Earth and

425
00:21:37,160 --> 00:21:39,400
Speaker 4: you put one of them in a spaceship. It goes

426
00:21:39,440 --> 00:21:41,080
Speaker 4: out into space at the speed of light and then

427
00:21:41,160 --> 00:21:44,840
Speaker 4: comes back and supposedly when they come back, they're a

428
00:21:44,840 --> 00:21:47,000
Speaker 4: different age than the one that stayed on Earth.

429
00:21:47,080 --> 00:21:49,320
Speaker 1: Yeah, this is a wonderful paradox because it gets to

430
00:21:49,359 --> 00:21:52,359
Speaker 1: the heart of like what actually happened, Because in the

431
00:21:52,359 --> 00:21:55,479
Speaker 1: example we're talking about, it feels awfully symmetric, right, Like

432
00:21:55,960 --> 00:21:58,320
Speaker 1: I'm looking at you through my telescope and I'm seeing

433
00:21:58,320 --> 00:22:01,680
Speaker 1: your clock tick slowly. But maybe on the ship you're

434
00:22:01,720 --> 00:22:04,439
Speaker 1: also looking at me on Earth and you see my

435
00:22:04,600 --> 00:22:06,720
Speaker 1: clock ticking slowly. So you want to feel like, well,

436
00:22:06,760 --> 00:22:09,080
Speaker 1: what actually happens. And the way to bring that to

437
00:22:09,119 --> 00:22:11,920
Speaker 1: a point is to like bring those two people back together.

438
00:22:12,359 --> 00:22:15,080
Speaker 1: So if one twin goes off on their spaceship, twin

439
00:22:15,119 --> 00:22:18,040
Speaker 1: on Earth sees the spaceship twin aging slowly, and the

440
00:22:18,080 --> 00:22:21,359
Speaker 1: spaceship twin sees the Earth twin aging slowly, and so

441
00:22:21,400 --> 00:22:23,760
Speaker 1: you want to feel like, well, which one is actually younger?

442
00:22:24,160 --> 00:22:26,679
Speaker 1: And so you turn the spaceship twin around, bring it

443
00:22:26,720 --> 00:22:28,920
Speaker 1: back to Earth, and you ask, like, well, which one

444
00:22:29,040 --> 00:22:31,560
Speaker 1: is younger? And what you discover is that the spaceship

445
00:22:31,600 --> 00:22:35,439
Speaker 1: twin is younger, and so that sort of breaks this symmetry,

446
00:22:35,680 --> 00:22:37,399
Speaker 1: and you wonder, like, hold on a second, if this

447
00:22:37,440 --> 00:22:39,439
Speaker 1: is supposed to be symmetric, if it just depends on

448
00:22:39,840 --> 00:22:43,040
Speaker 1: relative velocities, why is it that one of them is

449
00:22:43,119 --> 00:22:44,240
Speaker 1: now younger than the other.

450
00:22:44,440 --> 00:22:46,600
Speaker 4: So that means it's not just like a perception thing,

451
00:22:46,680 --> 00:22:49,840
Speaker 4: it's like time actually slowed down for the space twin.

452
00:22:50,080 --> 00:22:53,480
Speaker 1: In that case, it is because they've broken special relativity.

453
00:22:53,480 --> 00:22:56,640
Speaker 1: One of the rules of special relativity is no acceleration.

454
00:22:57,040 --> 00:22:59,040
Speaker 1: You can fly at high velocity and then you can

455
00:22:59,080 --> 00:23:01,640
Speaker 1: make all these measurements to do these calculations, and things

456
00:23:01,640 --> 00:23:05,000
Speaker 1: are just as we described. But as soon as you accelerate,

457
00:23:05,400 --> 00:23:08,200
Speaker 1: then you're out of the bounds of special relativity. It's

458
00:23:08,200 --> 00:23:10,119
Speaker 1: something you can do. You can do it, we can

459
00:23:10,160 --> 00:23:12,800
Speaker 1: calculate it. But it makes things more complicated, and the

460
00:23:12,840 --> 00:23:16,240
Speaker 1: simple rules we described earlier of moving clocks run slow

461
00:23:16,760 --> 00:23:19,119
Speaker 1: get much more tricky. So here. For example, when the

462
00:23:19,160 --> 00:23:22,800
Speaker 1: spaceship twin turns around to come back to Earth so

463
00:23:22,840 --> 00:23:25,960
Speaker 1: that he or she can compare her age with her twin,

464
00:23:26,400 --> 00:23:31,080
Speaker 1: then she's accelerating because changing your direction means accelerating. And

465
00:23:31,119 --> 00:23:33,440
Speaker 1: what happens when you accelerate is you break the symmetry.

466
00:23:33,520 --> 00:23:36,120
Speaker 1: Now one of the twins is accelerating, the other one

467
00:23:36,280 --> 00:23:40,879
Speaker 1: is not. And when you accelerate, weird things happen to time. Specifically,

468
00:23:40,880 --> 00:23:42,720
Speaker 1: when the twin that in the space ship turns around

469
00:23:42,760 --> 00:23:46,480
Speaker 1: and accelerates, time jumps forward for the rest of the universe.

470
00:23:46,760 --> 00:23:50,000
Speaker 1: So time runs a little slower for the accelerating twin

471
00:23:50,359 --> 00:23:52,720
Speaker 1: jumping forward for the rest of the universe, which is

472
00:23:52,720 --> 00:23:55,880
Speaker 1: why the twin in the spaceship now is younger when

473
00:23:55,880 --> 00:23:58,200
Speaker 1: they arrive at Earth than the twin that stayed home.

474
00:23:58,359 --> 00:24:00,199
Speaker 4: You just kind of accelerate it a little to as

475
00:24:00,240 --> 00:24:02,480
Speaker 4: there for my brain, I guess, one question is, but

476
00:24:02,600 --> 00:24:07,200
Speaker 4: isn't acceleration also relative, Like if I'm accelerating away from you,

477
00:24:07,680 --> 00:24:10,080
Speaker 4: I see you accelerating away from me, So why is

478
00:24:10,080 --> 00:24:14,760
Speaker 4: an acceleration also like kind of symmetric? And the second

479
00:24:14,840 --> 00:24:18,080
Speaker 4: question is you're saying it's the acceleration that causes time

480
00:24:18,119 --> 00:24:20,280
Speaker 4: to slow down, So that's sort of a different scenario.

481
00:24:20,640 --> 00:24:25,240
Speaker 1: Yeah, these are great questions. Acceleration is actually absolute. Velocity

482
00:24:25,320 --> 00:24:28,199
Speaker 1: can only be measured relative to other stuff. Like if

483
00:24:28,240 --> 00:24:31,200
Speaker 1: you're in an empty universe, you can't measure your velocity

484
00:24:31,240 --> 00:24:35,119
Speaker 1: because there's nothing to move past. Right, Velocity is only

485
00:24:35,160 --> 00:24:39,160
Speaker 1: defined only has meaning relative to other objects. That's not

486
00:24:39,320 --> 00:24:43,119
Speaker 1: true for acceleration. Acceleration is something you can measure, even

487
00:24:43,160 --> 00:24:46,040
Speaker 1: in an empty universe. So, for example, put yourself in

488
00:24:46,080 --> 00:24:49,160
Speaker 1: a spaceship. You're in an empty universe. If you're moving,

489
00:24:49,240 --> 00:24:52,280
Speaker 1: your motion has no meaning. There's no experiment you can

490
00:24:52,320 --> 00:24:56,040
Speaker 1: do inside your spaceship to measure your actual velocity because

491
00:24:56,040 --> 00:24:59,440
Speaker 1: there's nothing outside to measure relative too. That's not true

492
00:24:59,440 --> 00:25:03,080
Speaker 1: for acceleration. You can measure inside your spaceship whether or

493
00:25:03,119 --> 00:25:05,800
Speaker 1: not you're accelerating. For example, you can tell do I

494
00:25:05,920 --> 00:25:08,879
Speaker 1: feel a force by being pressed by one side of

495
00:25:08,920 --> 00:25:12,280
Speaker 1: the spaceship. You'll feel those g forces if you're accelerating.

496
00:25:12,320 --> 00:25:15,520
Speaker 1: So acceleration is different from velocity. You can't have an

497
00:25:15,560 --> 00:25:18,280
Speaker 1: absolute acceleration, you can measure it, and so that's why

498
00:25:18,320 --> 00:25:21,719
Speaker 1: the rules are different for acceleration and for velocity.

499
00:25:21,320 --> 00:25:23,080
Speaker 4: And so then you're saying that the twin who went

500
00:25:23,080 --> 00:25:26,080
Speaker 4: out into space will actually be younger when they come back.

501
00:25:25,920 --> 00:25:29,040
Speaker 1: They will actually be younger exactly. So when the twin

502
00:25:29,119 --> 00:25:31,080
Speaker 1: comes back to Earth and is now in the same

503
00:25:31,160 --> 00:25:34,520
Speaker 1: reference frame moving no velocity relative to the other twin,

504
00:25:34,800 --> 00:25:38,120
Speaker 1: then you can ask real questions about in this reference frame,

505
00:25:38,160 --> 00:25:40,960
Speaker 1: who is younger and who is older. And because the

506
00:25:41,000 --> 00:25:44,240
Speaker 1: twin that went into space also did some acceleration, their

507
00:25:44,280 --> 00:25:48,320
Speaker 1: time slowed down a lot during that acceleration, or equivalently,

508
00:25:48,600 --> 00:25:51,080
Speaker 1: time for the rest of the universe jumped forward during

509
00:25:51,080 --> 00:25:54,680
Speaker 1: that acceleration. So that breaks the symmetry because only one

510
00:25:54,760 --> 00:25:57,520
Speaker 1: twin accelerated, and so the twin that stay at home

511
00:25:57,600 --> 00:25:59,800
Speaker 1: actually is older. And you know this isn't just like

512
00:25:59,840 --> 00:26:03,440
Speaker 1: ad experiment. There actually are a pair of twin astronauts.

513
00:26:03,640 --> 00:26:05,360
Speaker 1: One of them went and spent a lot of time

514
00:26:05,400 --> 00:26:08,000
Speaker 1: up in space and the other one didn't, and they've

515
00:26:08,040 --> 00:26:08,840
Speaker 1: compared the two.

516
00:26:08,960 --> 00:26:11,760
Speaker 4: Really all right, well, let's get into that real life

517
00:26:11,760 --> 00:26:15,000
Speaker 4: experiment and then let's talk about how gravity changes time.

518
00:26:15,480 --> 00:26:17,119
Speaker 4: But first let's take a quick break.

519
00:26:21,440 --> 00:26:24,399
Speaker 1: With big wireless providers, what you see is never what

520
00:26:24,480 --> 00:26:27,160
Speaker 1: you get Somewhere between the store and your first month's bill,

521
00:26:27,200 --> 00:26:30,240
Speaker 1: the price you thought you were paying magically skyrockets. With

522
00:26:30,359 --> 00:26:33,800
Speaker 1: mint Mobile, You'll never have to worry about gotcha's ever again.

523
00:26:33,880 --> 00:26:36,119
Speaker 1: When Mint Mobile says fifteen dollars a month for a

524
00:26:36,119 --> 00:26:38,960
Speaker 1: three month plan, they really mean it. I've used mint

525
00:26:38,960 --> 00:26:41,440
Speaker 1: Mobile and the call quality is always so crisp and

526
00:26:41,520 --> 00:26:43,920
Speaker 1: so clear. I can recommend it to you. So say

527
00:26:43,960 --> 00:26:47,199
Speaker 1: bye bye to your overpriced wireless plans, jaw dropping monthly

528
00:26:47,240 --> 00:26:50,359
Speaker 1: bills and unexpected overages. You can use your own phone

529
00:26:50,440 --> 00:26:52,919
Speaker 1: with any Mint Mobile plan and bring your phone number

530
00:26:53,040 --> 00:26:56,320
Speaker 1: along with your existing contacts. So did your overpriced wireless

531
00:26:56,320 --> 00:26:58,720
Speaker 1: with mint Mobiles deal and get three months a premium

532
00:26:58,760 --> 00:27:01,199
Speaker 1: wireless service for fifteen bucks a month. To get this

533
00:27:01,240 --> 00:27:03,639
Speaker 1: new customer offer in your new three month premium wireless

534
00:27:03,680 --> 00:27:05,680
Speaker 1: plan for just fifteen bucks a month, go to mintmobile

535
00:27:05,720 --> 00:27:09,240
Speaker 1: dot com slash universe. That's mintmobile dot com slash universe.

536
00:27:09,240 --> 00:27:11,240
Speaker 1: Cut your wireless build a fifteen bucks a month at

537
00:27:11,240 --> 00:27:14,399
Speaker 1: mintmobile dot com slash universe. Forty five dollars upfront payment

538
00:27:14,400 --> 00:27:17,119
Speaker 1: required equivalent to fifteen dollars per month. New customers on

539
00:27:17,160 --> 00:27:19,960
Speaker 1: first three month plan only speeds slower about forty gigabytes

540
00:27:20,000 --> 00:27:22,480
Speaker 1: on unlimited plan. Additional taxi s fees and restrictions apply.

541
00:27:22,560 --> 00:27:24,000
Speaker 1: See mint mobile for details.

542
00:27:24,160 --> 00:27:27,200
Speaker 5: AI might be the most important new computer technology ever.

543
00:27:27,480 --> 00:27:30,679
Speaker 5: It's storming every industry and literally billions of dollars are

544
00:27:30,720 --> 00:27:34,920
Speaker 5: being invested, so buckle up. The problem is that AI

545
00:27:35,040 --> 00:27:37,880
Speaker 5: needs a lot of speed and processing power. So how

546
00:27:37,880 --> 00:27:41,040
Speaker 5: do you compete without cost spiraling out of control. It's

547
00:27:41,080 --> 00:27:43,399
Speaker 5: time to upgrade to the next generation of the cloud.

548
00:27:43,720 --> 00:27:48,920
Speaker 5: Oracle Cloud Infrastructure or OCI. OCI is a single platform

549
00:27:48,920 --> 00:27:53,800
Speaker 5: for your infrastructure, database, application development, and AI needs. OCI

550
00:27:53,960 --> 00:27:57,040
Speaker 5: has fourty eight times the bandwidth of other clouds, offers

551
00:27:57,080 --> 00:28:00,439
Speaker 5: one consistent price instead of variable regional pricing, and of

552
00:28:00,480 --> 00:28:03,560
Speaker 5: course nobody does data better than Oracle. So now you

553
00:28:03,560 --> 00:28:05,960
Speaker 5: can train your AI models at twice the speed and

554
00:28:06,040 --> 00:28:08,320
Speaker 5: less than half the cost of other clouds. If you

555
00:28:08,359 --> 00:28:10,800
Speaker 5: want to do more and spend less, like Uber eight

556
00:28:10,800 --> 00:28:13,480
Speaker 5: by eight and Data Bricks Mosaic, take a free test

557
00:28:13,520 --> 00:28:17,720
Speaker 5: drive of OCI at Oracle dot com slash strategic. That's

558
00:28:17,760 --> 00:28:22,760
Speaker 5: Oracle dot com slash Strategic Oracle dot com slash strategic.

559
00:28:23,000 --> 00:28:25,919
Speaker 1: If you love iPhone, you'll love Apple card. It's the

560
00:28:26,000 --> 00:28:29,879
Speaker 1: credit card designed for iPhone. It gives you unlimited daily

561
00:28:30,000 --> 00:28:32,960
Speaker 1: cash back that can earn four point four zero percent

562
00:28:33,119 --> 00:28:35,959
Speaker 1: annual percentage yield. When you open a high Yield savings

563
00:28:35,960 --> 00:28:39,520
Speaker 1: account through Applecard, apply for Applecard in the wallet app

564
00:28:39,600 --> 00:28:43,120
Speaker 1: subject to credit approval. Savings is available to Applecard owners

565
00:28:43,120 --> 00:28:46,400
Speaker 1: subject to eligibility Apple Card and Savings by Goldman Sachs

566
00:28:46,440 --> 00:28:49,840
Speaker 1: Bank USA, Salt Lake City Branch, Member FDIC terms and

567
00:28:49,960 --> 00:28:52,520
Speaker 1: more at applecard dot com. When you pop a piece

568
00:28:52,520 --> 00:28:55,040
Speaker 1: of cheese into your mouth or enjoy a rich spoonful

569
00:28:55,080 --> 00:28:58,560
Speaker 1: of Greek yogurt, you're probably not thinking about the environmental

570
00:28:58,600 --> 00:29:01,440
Speaker 1: impact of each and every bite, But the people in

571
00:29:01,440 --> 00:29:04,440
Speaker 1: the dairy industry are. US Dairy has set themselves some

572
00:29:04,560 --> 00:29:09,040
Speaker 1: ambitious sustainability goals, including being greenhouse gas neutral by twenty

573
00:29:09,040 --> 00:29:11,280
Speaker 1: to fifty. That's why they're working hard every day to

574
00:29:11,320 --> 00:29:14,200
Speaker 1: find new ways to reduce waste, conserve natural resources, and

575
00:29:14,280 --> 00:29:17,920
Speaker 1: drive down greenhouse gas emissions. Take water, for example, most

576
00:29:18,000 --> 00:29:21,120
Speaker 1: dairy farms reuse water up to four times. The same

577
00:29:21,160 --> 00:29:24,280
Speaker 1: water cools the milk, cleans equipment, washes the barn, and

578
00:29:24,440 --> 00:29:27,920
Speaker 1: irrigates the crops. How is US dairy tackling greenhouse gases.

579
00:29:27,960 --> 00:29:30,960
Speaker 1: Many farms use anaerobic digestors that turn the methane from

580
00:29:30,960 --> 00:29:34,360
Speaker 1: maneure into renewable energy that can power farms, towns, and

581
00:29:34,400 --> 00:29:36,640
Speaker 1: electric cars. So the next time you grab a slice

582
00:29:36,640 --> 00:29:38,560
Speaker 1: of pizza or lick an ice cream cone, know that

583
00:29:38,640 --> 00:29:41,280
Speaker 1: dairy farmers and processors around the country are using the

584
00:29:41,360 --> 00:29:45,120
Speaker 1: latest practices and innovations to provide the nutrient dense dairy

585
00:29:45,120 --> 00:29:48,160
Speaker 1: products we love with less of an impact. Visit usdairy

586
00:29:48,160 --> 00:29:50,440
Speaker 1: dot com slash sustainability to learn more.

587
00:29:58,680 --> 00:30:01,400
Speaker 4: All right, we're asking the question why does gravity slow

588
00:30:01,440 --> 00:30:04,440
Speaker 4: down time? And we were talking first about the twin

589
00:30:04,520 --> 00:30:07,400
Speaker 4: experiment where you send the tone out into space, they

590
00:30:07,400 --> 00:30:10,400
Speaker 4: go really fast, they come back and they've aged less.

591
00:30:11,400 --> 00:30:13,480
Speaker 4: And this age and you're saying is actually due to

592
00:30:13,560 --> 00:30:16,400
Speaker 4: the acceleration, it's not actually due to the speed. Right.

593
00:30:16,520 --> 00:30:19,160
Speaker 1: There are two effects there. There's the velocity time delation,

594
00:30:19,200 --> 00:30:21,520
Speaker 1: which is the one you're very familiar with where moving

595
00:30:21,560 --> 00:30:24,960
Speaker 1: clocks appear to be slow. But that's not a universal phenomenon.

596
00:30:24,960 --> 00:30:27,440
Speaker 1: It depends on who is doing the observing and their

597
00:30:27,480 --> 00:30:31,640
Speaker 1: relative velocity. Acceleration, however, is different, and the acceleration does

598
00:30:31,800 --> 00:30:35,560
Speaker 1: cause an actual slowing of time, which can be measured

599
00:30:35,600 --> 00:30:39,320
Speaker 1: by everybody because it's not symmetric, it's absolute. You can

600
00:30:39,400 --> 00:30:43,040
Speaker 1: measure somebody's absolute acceleration and that makes them different, so

601
00:30:43,080 --> 00:30:44,280
Speaker 1: it breaks the symmetry.

602
00:30:44,360 --> 00:30:46,720
Speaker 4: So really, when people say going fast slows down time,

603
00:30:46,720 --> 00:30:49,880
Speaker 4: we really reaching to be saying accelerating fast causes time

604
00:30:49,920 --> 00:30:53,200
Speaker 4: to slow. And is that something that just somehow changes

605
00:30:53,280 --> 00:30:55,880
Speaker 4: time or is it because you're pushing all of the

606
00:30:55,960 --> 00:30:59,960
Speaker 4: particles and somehow that slows how they interact, or how

607
00:31:00,000 --> 00:31:02,320
Speaker 4: how do you explain acceleration changing time?

608
00:31:02,440 --> 00:31:04,280
Speaker 1: Well, first of all, it is still correct to say

609
00:31:04,280 --> 00:31:06,760
Speaker 1: that moving fast slows down time. It's just that it

610
00:31:06,760 --> 00:31:10,720
Speaker 1: slows down time only for observers, right, observers moving fast

611
00:31:10,800 --> 00:31:13,760
Speaker 1: relative to those clocks. It's still true, it still happens.

612
00:31:13,600 --> 00:31:16,320
Speaker 1: It's not like just a perception issue. It's a true

613
00:31:16,360 --> 00:31:19,320
Speaker 1: thing about the universe. Acceleration slows down time in a

614
00:31:19,320 --> 00:31:21,840
Speaker 1: different way. It's a different mechanism. It's much harder to

615
00:31:21,920 --> 00:31:24,880
Speaker 1: understand in terms of its like ticks on the photon clock.

616
00:31:25,120 --> 00:31:27,400
Speaker 1: But you can see it also comes as a consequence

617
00:31:27,480 --> 00:31:28,480
Speaker 1: of the speed of light.

618
00:31:28,640 --> 00:31:31,400
Speaker 4: All right, Well, then, so that's acceleration and time dilation.

619
00:31:31,600 --> 00:31:35,040
Speaker 4: Because of acceleration and because of going close to the

620
00:31:35,080 --> 00:31:36,840
Speaker 4: speed of light. But the one we're talking about today

621
00:31:36,880 --> 00:31:40,360
Speaker 4: is the one due to gravity. So whenever you're next

622
00:31:40,440 --> 00:31:45,120
Speaker 4: to something that's really heavy or massive, time also slows down.

623
00:31:45,800 --> 00:31:48,480
Speaker 4: But does it slow down in the same way that

624
00:31:48,560 --> 00:31:51,160
Speaker 4: acceleration slows time down? Or does it slow down in

625
00:31:51,200 --> 00:31:53,960
Speaker 4: the same way that going at a constant speed slows time?

626
00:31:54,000 --> 00:31:55,320
Speaker 4: Do you know what I mean? Like, is it observer

627
00:31:55,440 --> 00:31:57,760
Speaker 4: base or is it actually like time slowing down?

628
00:31:57,840 --> 00:32:01,640
Speaker 1: Yeah, great question. And gravity slows down time or the

629
00:32:01,720 --> 00:32:05,520
Speaker 1: curvature of space slows down time, And this effect on

630
00:32:05,600 --> 00:32:09,920
Speaker 1: time is the same as acceleration slowing down time. And

631
00:32:09,960 --> 00:32:12,680
Speaker 1: in fact, it's sort of a deep idea here because

632
00:32:12,760 --> 00:32:16,400
Speaker 1: in general relativity, one of the whole inspirational ideas of

633
00:32:16,440 --> 00:32:20,680
Speaker 1: general relativity is that gravity is equivalent to acceleration. You

634
00:32:20,680 --> 00:32:22,600
Speaker 1: know the experiment we talked about a minute ago, like

635
00:32:22,720 --> 00:32:25,240
Speaker 1: if you were in space, could you tell if your

636
00:32:25,280 --> 00:32:28,280
Speaker 1: spaceship was accelerating? You could, and in fact it would

637
00:32:28,280 --> 00:32:30,600
Speaker 1: feel like you were being pressed against one wall of

638
00:32:30,640 --> 00:32:34,120
Speaker 1: the ship, or equivalently, it would feel like you were

639
00:32:34,160 --> 00:32:37,200
Speaker 1: standing on a planet with gravity. Right, You can in

640
00:32:37,200 --> 00:32:40,880
Speaker 1: fact make artificial gravity on a spaceship by providing acceleration

641
00:32:41,160 --> 00:32:43,760
Speaker 1: either by spinning or by zooming off in one direction.

642
00:32:44,280 --> 00:32:47,600
Speaker 1: So the whole idea that gave Einstein the inspiration for

643
00:32:47,720 --> 00:32:50,760
Speaker 1: general relativity was this one is called the equivalence principle

644
00:32:51,000 --> 00:32:55,000
Speaker 1: that says that there's no difference between gravity and acceleration.

645
00:32:55,400 --> 00:32:57,920
Speaker 1: And so we just went through the details of how

646
00:32:58,000 --> 00:33:02,080
Speaker 1: acceleration can cause time to move slowly, and this is

647
00:33:02,160 --> 00:33:06,000
Speaker 1: exactly the same effect. Gravity also makes time move slowly.

648
00:33:06,160 --> 00:33:10,680
Speaker 1: The curvature of space around you makes time move more slowly.

649
00:33:10,720 --> 00:33:13,560
Speaker 1: It's exactly the same effect, and so it's an absolute effect,

650
00:33:13,800 --> 00:33:15,960
Speaker 1: not a relative one like for velocity.

651
00:33:16,080 --> 00:33:18,720
Speaker 4: So you're saying, it's really sort of acceleration that costs

652
00:33:18,880 --> 00:33:21,880
Speaker 4: time to slow down, and gravity is sort of like

653
00:33:21,880 --> 00:33:24,280
Speaker 4: an acceleration, or is it the other way around, But

654
00:33:24,320 --> 00:33:26,600
Speaker 4: I guess you can have acceleration without gravity, so it's

655
00:33:26,600 --> 00:33:28,960
Speaker 4: more like gravity is kind of like an acceleration.

656
00:33:29,120 --> 00:33:33,600
Speaker 1: Yeah, gravity is essentially like a geometrical interpretation of acceleration,

657
00:33:33,840 --> 00:33:36,480
Speaker 1: or you know, said another way, what happens when you

658
00:33:36,520 --> 00:33:40,240
Speaker 1: have mass in space, Well, it changes the curvature of

659
00:33:40,320 --> 00:33:43,120
Speaker 1: that space, and so what happens then is that things

660
00:33:43,200 --> 00:33:46,880
Speaker 1: move differently, and they can appear, for example, to be accelerating.

661
00:33:47,200 --> 00:33:49,920
Speaker 1: If you aren't aware of the curvature of space, then

662
00:33:50,040 --> 00:33:52,320
Speaker 1: it seems like there's a force there which provides an

663
00:33:52,360 --> 00:33:56,760
Speaker 1: acceleration towards those masses. And so that's really what gravity is.

664
00:33:56,800 --> 00:33:59,520
Speaker 1: Gravity is the bending of space in a way that

665
00:33:59,640 --> 00:34:03,720
Speaker 1: appears to provide acceleration. So gravity and acceleration really are

666
00:34:03,880 --> 00:34:08,000
Speaker 1: exactly the same phenomenon. Either acceleration in empty flat space

667
00:34:08,080 --> 00:34:11,960
Speaker 1: gives exactly the same effects as curving of space itself.

668
00:34:12,160 --> 00:34:15,280
Speaker 1: You remember, we did recently a fun episode about how

669
00:34:15,360 --> 00:34:19,799
Speaker 1: if you're accelerating there are times that photons cannot catch you.

670
00:34:19,800 --> 00:34:23,480
Speaker 1: You have essentially an event horizon if you're accelerating constantly.

671
00:34:23,920 --> 00:34:26,239
Speaker 1: And the explanation there was the same as here, is

672
00:34:26,239 --> 00:34:30,520
Speaker 1: that accelerating constantly is sort of the same as curving space.

673
00:34:30,880 --> 00:34:33,320
Speaker 1: And we know that if you curve space, weird things happen,

674
00:34:33,440 --> 00:34:35,840
Speaker 1: like you can be inside a black hole and photons

675
00:34:35,840 --> 00:34:38,920
Speaker 1: cannot escape. And so the core idea here is to

676
00:34:39,000 --> 00:34:42,560
Speaker 1: understand that accelerating is really the same thing as gravity,

677
00:34:42,760 --> 00:34:45,880
Speaker 1: And so if you think of gravity as causing time dilation,

678
00:34:46,120 --> 00:34:49,440
Speaker 1: it's really the concept of acceleration causing time dilation. That's

679
00:34:49,440 --> 00:34:50,759
Speaker 1: sort of mentally equivalent.

680
00:34:51,080 --> 00:34:52,719
Speaker 4: There are a lot of leaps here, I feel like,

681
00:34:52,920 --> 00:34:54,920
Speaker 4: and it's kind of hard to keep track of because

682
00:34:55,000 --> 00:34:58,720
Speaker 4: I feel like you're saying gravity is acceleration and gravity

683
00:34:58,800 --> 00:35:01,640
Speaker 4: is also the curvature of space. Does that mean that

684
00:35:01,680 --> 00:35:05,279
Speaker 4: all acceleration is also the curvature of space? Or can

685
00:35:05,320 --> 00:35:08,960
Speaker 4: you have acceleration in not bend space, or like, can

686
00:35:09,000 --> 00:35:12,080
Speaker 4: you think of all acceleration even by like electromagnetic forces,

687
00:35:12,560 --> 00:35:14,240
Speaker 4: as some sort of curvature of space.

688
00:35:14,320 --> 00:35:16,440
Speaker 1: Yeah, that's a deep question, and there are people out

689
00:35:16,480 --> 00:35:19,680
Speaker 1: there trying to interpret all acceleration in terms of the

690
00:35:19,680 --> 00:35:23,120
Speaker 1: curvature of space, or you know, like all forces as

691
00:35:23,160 --> 00:35:25,600
Speaker 1: being the product of the curvature of space. But that's

692
00:35:25,640 --> 00:35:29,600
Speaker 1: not necessary. You can think about acceleration in flat space,

693
00:35:29,800 --> 00:35:32,200
Speaker 1: you know, just like put on a rocket ship, accelerate

694
00:35:32,239 --> 00:35:35,239
Speaker 1: your spaceship. Now you're going fast. But the effects of

695
00:35:35,320 --> 00:35:37,800
Speaker 1: that on your time and the way you pursue the

696
00:35:37,880 --> 00:35:41,840
Speaker 1: universe are equivalent to if space was curved around you.

697
00:35:42,320 --> 00:35:44,960
Speaker 1: So you can think of acceleration separately from the curvature

698
00:35:44,960 --> 00:35:47,279
Speaker 1: of space and from gravity, but has exactly the same

699
00:35:47,320 --> 00:35:49,960
Speaker 1: effect because that's really kind of what gravity.

700
00:35:49,640 --> 00:35:51,959
Speaker 4: Is, so meaning I feel like then that you're saying

701
00:35:51,960 --> 00:35:56,200
Speaker 4: that it's not really gravity that's slowing down time. It's

702
00:35:56,320 --> 00:35:59,040
Speaker 4: really the acceleration caused by gravity, or the bending of

703
00:35:59,080 --> 00:36:02,160
Speaker 4: space caused by which is the same as acceleration.

704
00:36:02,280 --> 00:36:04,080
Speaker 1: Yeah, there's lots of different ways to think about it.

705
00:36:04,280 --> 00:36:07,120
Speaker 1: You can think of acceleration caused by gravity as really

706
00:36:07,200 --> 00:36:10,600
Speaker 1: just like motion through curved space, and one of the

707
00:36:10,600 --> 00:36:14,600
Speaker 1: other impacts of curve space is that time also slows down.

708
00:36:14,800 --> 00:36:17,399
Speaker 4: All right, well, then maybe let's try it. Let's see

709
00:36:17,400 --> 00:36:21,040
Speaker 4: why does acceleration slow down time? Because that seems to

710
00:36:21,080 --> 00:36:22,920
Speaker 4: be the bigger problem, right, that seems to be the

711
00:36:22,920 --> 00:36:23,840
Speaker 4: bigger question.

712
00:36:24,040 --> 00:36:26,880
Speaker 1: Yeah, so I guess you can say that gravity slows

713
00:36:26,880 --> 00:36:30,279
Speaker 1: down time because it's equivalent to acceleration slowing down time.

714
00:36:30,560 --> 00:36:33,400
Speaker 1: Why does acceleration slow down time? That gets back to

715
00:36:33,840 --> 00:36:36,680
Speaker 1: the speed of light as the limiting piece of information.

716
00:36:36,920 --> 00:36:39,160
Speaker 1: You can derive this in a flat universe using the

717
00:36:39,200 --> 00:36:41,880
Speaker 1: twins as an example. It's a little bit more complicated

718
00:36:41,960 --> 00:36:45,279
Speaker 1: mathematically than like normal special relativity, where you can do

719
00:36:45,320 --> 00:36:48,600
Speaker 1: these observing frames with Lorentz transformations. It gets a little

720
00:36:48,680 --> 00:36:52,120
Speaker 1: hairy and mathematical, but the core concept that it comes

721
00:36:52,120 --> 00:36:56,399
Speaker 1: from is this maximum speed of light. Everything comes out

722
00:36:56,400 --> 00:37:00,000
Speaker 1: of that, both time dilation from velocity and also time

723
00:37:00,080 --> 00:37:03,840
Speaker 1: doleation from acceleration, which really is equivalent to time dolation

724
00:37:03,960 --> 00:37:04,600
Speaker 1: from gravity.

725
00:37:04,800 --> 00:37:06,560
Speaker 4: So I guess if I'm in a spaceship and I'm

726
00:37:06,600 --> 00:37:10,279
Speaker 4: accelerating the limitations of the speed of light, which does

727
00:37:10,280 --> 00:37:11,960
Speaker 4: that mean that? Are you sort of saying that it

728
00:37:12,160 --> 00:37:16,280
Speaker 4: somehow limits how the things can evolve inside of that spaceship,

729
00:37:16,360 --> 00:37:20,160
Speaker 4: you know, move from you know, information between molecules and

730
00:37:20,160 --> 00:37:23,120
Speaker 4: things like that, so things sort of evolve slower or

731
00:37:23,160 --> 00:37:24,920
Speaker 4: they have a limit to how fast it can evolve.

732
00:37:25,120 --> 00:37:27,560
Speaker 1: Yeah, I would say a little bit differently. I would

733
00:37:27,560 --> 00:37:31,000
Speaker 1: say that requiring that the speed of light is constant

734
00:37:31,080 --> 00:37:33,279
Speaker 1: and that everybody observes the speed of light always to

735
00:37:33,320 --> 00:37:37,000
Speaker 1: be the speed of light restricts the kinds of universes

736
00:37:37,000 --> 00:37:39,879
Speaker 1: that we can have. It puts a lot of restrictions

737
00:37:39,960 --> 00:37:42,399
Speaker 1: on the way space and time have to work in

738
00:37:42,400 --> 00:37:45,640
Speaker 1: that universe. And these effects that we're talking about, the

739
00:37:46,000 --> 00:37:49,879
Speaker 1: slowing down of time by velocity and by acceleration, are

740
00:37:49,960 --> 00:37:52,880
Speaker 1: consequences of the structure of that space and time. The

741
00:37:53,000 --> 00:37:54,640
Speaker 1: sort of come out of that.

742
00:37:54,719 --> 00:37:56,440
Speaker 4: All right, So you're saying it's just the way it is.

743
00:37:58,040 --> 00:38:00,680
Speaker 4: When things accelerate, there's a limit in this speed of light,

744
00:38:01,040 --> 00:38:04,040
Speaker 4: and so that makes time sort of slow down, makes

745
00:38:04,080 --> 00:38:04,839
Speaker 4: everything slow down.

746
00:38:05,239 --> 00:38:08,160
Speaker 1: And I think it's super cool because it's not symmetric.

747
00:38:08,320 --> 00:38:10,759
Speaker 1: You know, like two people can agree on who is

748
00:38:10,800 --> 00:38:13,800
Speaker 1: accelerating more, and so that means that they can agree

749
00:38:14,000 --> 00:38:16,840
Speaker 1: on whose time is moving more slowly, or you know,

750
00:38:16,920 --> 00:38:19,840
Speaker 1: said another way in terms of gravity, like you and

751
00:38:19,920 --> 00:38:22,400
Speaker 1: I can agree that if you're near the black hole,

752
00:38:22,719 --> 00:38:25,080
Speaker 1: then you're in a part of space that's curved more

753
00:38:25,160 --> 00:38:27,600
Speaker 1: than my part of space, and so we can agree

754
00:38:27,719 --> 00:38:30,560
Speaker 1: that your time should be moving more slowly. That's not

755
00:38:30,600 --> 00:38:33,040
Speaker 1: true for the spaceships, right, If we're in two spaceships

756
00:38:33,080 --> 00:38:35,800
Speaker 1: passing each other, it feels symmetric because it is symmetric.

757
00:38:36,000 --> 00:38:38,160
Speaker 1: I say you're moving past me, you say I'm moving

758
00:38:38,160 --> 00:38:41,359
Speaker 1: past you. Everybody's right. In the case of the black hole,

759
00:38:41,440 --> 00:38:44,280
Speaker 1: we can agree it's not symmetric, so we should agree

760
00:38:44,320 --> 00:38:46,080
Speaker 1: that your time is moving more slowly.

761
00:38:46,160 --> 00:38:48,680
Speaker 4: So then a coloration causes time to slow down. And definitely,

762
00:38:48,680 --> 00:38:50,719
Speaker 4: when you're in near a black hole, you are being

763
00:38:50,800 --> 00:38:55,040
Speaker 4: accelerated probably a lot, because black holes are very massive.

764
00:38:55,080 --> 00:38:57,640
Speaker 4: They're pulling you in. And so if I'm near a

765
00:38:57,640 --> 00:39:00,719
Speaker 4: black hole, then I'm going to be moving slower through

766
00:39:00,719 --> 00:39:03,200
Speaker 4: time than you, who is out way far from the

767
00:39:03,280 --> 00:39:04,400
Speaker 4: black hole exactly.

768
00:39:04,960 --> 00:39:07,560
Speaker 1: And so another cool thing is that I see your

769
00:39:07,600 --> 00:39:10,720
Speaker 1: time moving slowly. It means that you see my time

770
00:39:10,960 --> 00:39:14,040
Speaker 1: moving more quickly. Right, This is the real difference with

771
00:39:14,160 --> 00:39:17,279
Speaker 1: velocity time dilation and velocity time dilation. We both see

772
00:39:17,320 --> 00:39:19,920
Speaker 1: each other's time moving more slowly. Here, if you're near

773
00:39:19,960 --> 00:39:21,880
Speaker 1: a black hole and you're looking out into the universe,

774
00:39:22,160 --> 00:39:24,480
Speaker 1: you see the rest of the universe running forward in

775
00:39:24,560 --> 00:39:27,080
Speaker 1: time very quickly. And as you get closer and closer

776
00:39:27,120 --> 00:39:29,200
Speaker 1: to the black hole and more and more curvature, you

777
00:39:29,280 --> 00:39:31,960
Speaker 1: see the universe's clocks speeding up into the future.

778
00:39:32,040 --> 00:39:34,360
Speaker 4: So then like if I'm falling into a black hole,

779
00:39:34,960 --> 00:39:37,799
Speaker 4: like all the stars will suddenly start speeding up around me,

780
00:39:38,160 --> 00:39:40,640
Speaker 4: like I'll see the universe kind of and fast forward exactly.

781
00:39:40,680 --> 00:39:42,480
Speaker 1: And some people imagine, well, does that mean that you'll

782
00:39:42,560 --> 00:39:45,560
Speaker 1: see like the end of the universe, the end of time.

783
00:39:45,719 --> 00:39:47,960
Speaker 1: You'll know like the final fate of the universe just

784
00:39:48,040 --> 00:39:50,399
Speaker 1: as you fall into the black hole. Well, that would

785
00:39:50,400 --> 00:39:53,360
Speaker 1: be super cool, But unfortunately, it takes a finite amount

786
00:39:53,360 --> 00:39:56,239
Speaker 1: of time from your perspective to fall into a black hole,

787
00:39:56,280 --> 00:39:58,880
Speaker 1: so there isn't time for all that information from the

788
00:39:58,880 --> 00:40:01,640
Speaker 1: future universe to get to you. So you see the

789
00:40:01,680 --> 00:40:04,000
Speaker 1: fast forwarded universe for a while, but you don't see

790
00:40:04,080 --> 00:40:06,280
Speaker 1: like all the way into the infinite future.

791
00:40:06,320 --> 00:40:08,040
Speaker 4: Well, we talked about this last time, Like when you

792
00:40:08,080 --> 00:40:10,799
Speaker 4: actually get to the surface of the black hole, then

793
00:40:11,520 --> 00:40:14,920
Speaker 4: time actually stands still, right, Like, it slows down more

794
00:40:14,960 --> 00:40:17,080
Speaker 4: the closer you get to the black hole, and then

795
00:40:17,120 --> 00:40:18,640
Speaker 4: it sort of stands still at the surface.

796
00:40:18,760 --> 00:40:21,560
Speaker 1: It sort of does, but that's only for somebody far away.

797
00:40:22,000 --> 00:40:25,160
Speaker 1: They see your time moving slowly and they see you

798
00:40:25,200 --> 00:40:29,439
Speaker 1: sort of smeared across the event horizon. But for you, you

799
00:40:28,960 --> 00:40:32,040
Speaker 1: actually fall into the black hole, you don't notice anything

800
00:40:32,080 --> 00:40:34,880
Speaker 1: different changing, right, You notice the rest of the universe's

801
00:40:34,880 --> 00:40:37,560
Speaker 1: clocks speeding up, But from your perspective, you fall into

802
00:40:37,600 --> 00:40:39,919
Speaker 1: the black hole, you pass the event horizon, you get

803
00:40:39,960 --> 00:40:43,560
Speaker 1: sucked into the singularity, So your time is definitely finite

804
00:40:43,640 --> 00:40:46,000
Speaker 1: from your perspective. And this is not something that we

805
00:40:46,080 --> 00:40:48,880
Speaker 1: understand very well. There's all sorts of weird paradoxes and

806
00:40:48,920 --> 00:40:51,600
Speaker 1: contradictions here about how one person sees you not falling

807
00:40:51,640 --> 00:40:53,839
Speaker 1: into the black hole into the end of time, and

808
00:40:53,920 --> 00:40:56,759
Speaker 1: you see yourself actually falling in. It's not something that

809
00:40:56,800 --> 00:40:58,160
Speaker 1: we know how to reconcile.

810
00:40:58,200 --> 00:41:00,120
Speaker 4: I think what you're saying is that the person fall

811
00:41:00,120 --> 00:41:02,719
Speaker 4: and then you're saying they'll see themselves falling through, But

812
00:41:02,800 --> 00:41:04,719
Speaker 4: we don't actually know if that's true, right, Like they

813
00:41:04,800 --> 00:41:07,560
Speaker 4: might just actually freeze the edge. We just don't know.

814
00:41:07,840 --> 00:41:10,080
Speaker 1: Yeah, we don't know it's true, because nobody's done it

815
00:41:10,120 --> 00:41:12,719
Speaker 1: and come to report back. It's possible they actually just

816
00:41:12,760 --> 00:41:15,239
Speaker 1: freeze the edge and they think that they're inside, but

817
00:41:15,280 --> 00:41:17,360
Speaker 1: it's actually that the inside of a black hole is

818
00:41:17,400 --> 00:41:20,440
Speaker 1: a hologram projected from the surface of the black hole.

819
00:41:20,760 --> 00:41:23,279
Speaker 1: We just don't really know what's going on inside a

820
00:41:23,360 --> 00:41:23,880
Speaker 1: black hole.

821
00:41:24,080 --> 00:41:27,319
Speaker 4: And so this effect of gravity on time doesn't just

822
00:41:27,360 --> 00:41:29,799
Speaker 4: happen in black holes. I mean, black hole is sort

823
00:41:29,800 --> 00:41:32,680
Speaker 4: of the extreme example, but it actually happens like every

824
00:41:32,760 --> 00:41:35,640
Speaker 4: day and everywhere, like here on Earth, the Earth is

825
00:41:35,680 --> 00:41:38,680
Speaker 4: slowing down time and even like I'm slowing down time

826
00:41:39,120 --> 00:41:40,200
Speaker 4: for the things around me, right.

827
00:41:40,200 --> 00:41:44,680
Speaker 1: Yeah, absolutely, everywhere there's curvature. Time is slowed down and

828
00:41:44,760 --> 00:41:47,480
Speaker 1: the Earth curves space right, because the Earth has a

829
00:41:47,520 --> 00:41:49,839
Speaker 1: lot of mass. That's why, for example, you don't fall

830
00:41:49,880 --> 00:41:52,719
Speaker 1: off the Earth. You're feeling it's gravity. So anywhere you're

831
00:41:52,760 --> 00:41:55,640
Speaker 1: in a situation where you're feeling gravity, you're also having

832
00:41:55,680 --> 00:41:58,960
Speaker 1: your time affected. And because gravity is stronger as you

833
00:41:59,000 --> 00:42:01,319
Speaker 1: get closer to the Earth and weaker as you move

834
00:42:01,440 --> 00:42:04,360
Speaker 1: away from it, that means that the clocks are variable.

835
00:42:04,600 --> 00:42:07,360
Speaker 1: Time flows in a variable way as a function of

836
00:42:07,400 --> 00:42:10,040
Speaker 1: the distance from the center of the Earth. And this

837
00:42:10,120 --> 00:42:13,160
Speaker 1: is something you can measure, like over your life, your

838
00:42:13,200 --> 00:42:16,760
Speaker 1: feet will age one second more than your.

839
00:42:16,719 --> 00:42:19,760
Speaker 4: Head only if you spend a lot of time standing

840
00:42:19,840 --> 00:42:22,680
Speaker 4: up Daniel, which cartoonist don't a lot of. So I

841
00:42:22,680 --> 00:42:24,879
Speaker 4: guess our feet are still young. We are still light

842
00:42:24,920 --> 00:42:25,319
Speaker 4: on our feet.

843
00:42:25,360 --> 00:42:27,279
Speaker 1: Yeah, exactly. That's why you lay down all the time,

844
00:42:27,360 --> 00:42:29,400
Speaker 1: just to keep your body like in sync.

845
00:42:29,480 --> 00:42:32,319
Speaker 4: Just to keep my feet young. All right, Well, let's

846
00:42:32,320 --> 00:42:35,359
Speaker 4: get into what this all means. Does that mean that

847
00:42:35,440 --> 00:42:38,480
Speaker 4: we're all moving slower through time than we should and

848
00:42:38,960 --> 00:42:42,040
Speaker 4: whether does that mean that also there's no universal clock

849
00:42:42,239 --> 00:42:45,359
Speaker 4: actually to measure time in the universe, So let's get

850
00:42:45,360 --> 00:42:45,680
Speaker 4: into that.

851
00:42:45,719 --> 00:42:52,919
Speaker 1: But first let's take another quick break. When you pop

852
00:42:52,920 --> 00:42:54,840
Speaker 1: a piece of cheese into your mouth or enjoy a

853
00:42:54,920 --> 00:42:58,320
Speaker 1: rich spoonful of greeky yogurt, you're probably not thinking about

854
00:42:58,320 --> 00:43:01,719
Speaker 1: the environmental impact of each and every bite, But the

855
00:43:01,760 --> 00:43:04,560
Speaker 1: people in the dairy industry are. US Dairy has set

856
00:43:04,600 --> 00:43:09,200
Speaker 1: themselves some ambitious sustainability goals, including being greenhouse gas neutral

857
00:43:09,239 --> 00:43:11,640
Speaker 1: by twenty to fifty. That's why they're working hard every

858
00:43:11,719 --> 00:43:14,800
Speaker 1: day to find new ways to reduce waste, conserve natural resources,

859
00:43:14,800 --> 00:43:18,360
Speaker 1: and drive down greenhouse gas emissions. Take water, for example,

860
00:43:18,440 --> 00:43:21,520
Speaker 1: most dairy farms reuse water up to four times the

861
00:43:21,560 --> 00:43:24,800
Speaker 1: same water cools the milk, cleans equipment, washes the barn,

862
00:43:24,880 --> 00:43:28,600
Speaker 1: and irrigates the crops. How is US dairy tackling greenhouse gases?

863
00:43:28,640 --> 00:43:31,640
Speaker 1: Many farms use anaerobic digestors that turn the methane from

864
00:43:31,680 --> 00:43:35,080
Speaker 1: maneuver into renewable energy that can power farms, towns, and

865
00:43:35,120 --> 00:43:37,360
Speaker 1: electric cars. So the next time you grab a slice

866
00:43:37,360 --> 00:43:39,239
Speaker 1: of pizza or lick an ice cream cone, know that

867
00:43:39,320 --> 00:43:41,960
Speaker 1: dairy farmers and processors around the country are using the

868
00:43:42,080 --> 00:43:45,800
Speaker 1: latest practices and innovations to provide the nutrient dense dairy

869
00:43:45,840 --> 00:43:48,840
Speaker 1: products we love with less of an impact. Visit usdairy

870
00:43:48,880 --> 00:43:51,120
Speaker 1: dot com slash sustainability to learn more.

871
00:43:51,800 --> 00:43:55,319
Speaker 14: Hi, I'm David Eagleman from the podcast Inner Cosmos, which

872
00:43:55,360 --> 00:43:58,640
Speaker 14: recently hit the number one science podcast in America. I

873
00:43:58,719 --> 00:44:02,680
Speaker 14: mean neuroscientists sustain and I've spent my career exploring the

874
00:44:02,760 --> 00:44:05,640
Speaker 14: three pound universe in our heads. We're looking at a

875
00:44:05,680 --> 00:44:09,320
Speaker 14: whole new series of episodes this season to understand why

876
00:44:09,400 --> 00:44:12,680
Speaker 14: and how our lives look the way they do. Why

877
00:44:12,719 --> 00:44:15,880
Speaker 14: does your memory drift so much? Why is it so

878
00:44:16,120 --> 00:44:19,880
Speaker 14: hard to keep a secret, When should you not trust

879
00:44:19,880 --> 00:44:24,360
Speaker 14: your intuition? Why do brains so easily fall for magic tricks?

880
00:44:24,600 --> 00:44:28,040
Speaker 14: And why do they love conspiracy theories. I'm hitting these

881
00:44:28,160 --> 00:44:31,920
Speaker 14: questions and hundreds more because the more we know about

882
00:44:31,960 --> 00:44:34,880
Speaker 14: what's running under the hood, the better we can steer

883
00:44:35,000 --> 00:44:35,840
Speaker 14: our lives.

884
00:44:36,520 --> 00:44:39,600
Speaker 2: Join me weekly to explore the relationship.

885
00:44:38,920 --> 00:44:43,600
Speaker 14: Between your brain and your life by digging into unexpected questions.

886
00:44:44,200 --> 00:44:48,200
Speaker 14: Listen to Inner Cosmos with David Eagleman on the iHeartRadio app, Apple.

887
00:44:47,960 --> 00:44:50,480
Speaker 4: Podcasts, or wherever you get your podcasts.

888
00:44:52,800 --> 00:44:55,440
Speaker 13: Hi, everyone, it's me Katie Couric. If you follow me

889
00:44:55,480 --> 00:44:57,880
Speaker 13: on social media, you know I love to cook, or

890
00:44:57,880 --> 00:45:01,440
Speaker 13: at least try especially along side some of my favorite

891
00:45:01,520 --> 00:45:05,400
Speaker 13: chefs and foodies like Benny Blanco, Jake Cohen, Lighty hoych

892
00:45:05,560 --> 00:45:09,680
Speaker 13: Alison Roman, and of course Inagarten and Martha Stewart. So

893
00:45:09,760 --> 00:45:12,919
Speaker 13: I started a free newsletter called Good Taste that comes

894
00:45:12,960 --> 00:45:16,439
Speaker 13: out every Thursday, and it's serving up recipes that will

895
00:45:16,440 --> 00:45:20,520
Speaker 13: make your mouth water. Think a candied bacon, bloody mary

896
00:45:20,880 --> 00:45:24,839
Speaker 13: tacos with cabbage slaw, curry cauliflower with almonds and mint,

897
00:45:25,120 --> 00:45:28,160
Speaker 13: and cherry slab pie with vanilla ice cream to top

898
00:45:28,200 --> 00:45:31,160
Speaker 13: it all off. I mean, young, I'm getting hungry. But

899
00:45:31,239 --> 00:45:34,280
Speaker 13: if you're not sold yet, we also have kitchen tips

900
00:45:34,320 --> 00:45:36,760
Speaker 13: like a fool proof way to grill the perfect burger

901
00:45:36,960 --> 00:45:39,960
Speaker 13: and must have products like the best cast iron skillet.

902
00:45:40,160 --> 00:45:42,560
Speaker 13: To feel like a chef in your own kitchen. All

903
00:45:42,560 --> 00:45:44,680
Speaker 13: you need to do is sign up at Katiecuric dot

904
00:45:44,719 --> 00:45:48,000
Speaker 13: com slash good Taste. That's k A T I E

905
00:45:48,280 --> 00:45:52,040
Speaker 13: c o u r ic dot com slash good Taste.

906
00:45:52,400 --> 00:45:56,080
Speaker 13: I promise your taste buds will be happy you did.

907
00:45:56,800 --> 00:45:57,560
Speaker 15: Guess what BANNGO?

908
00:45:57,800 --> 00:45:58,120
Speaker 16: What's that?

909
00:45:58,239 --> 00:45:58,439
Speaker 2: Well?

910
00:45:58,640 --> 00:46:01,080
Speaker 15: So iHeart is giving us a whole minute to promote

911
00:46:01,120 --> 00:46:02,920
Speaker 15: our podcast, Part time Genius.

912
00:46:03,239 --> 00:46:05,200
Speaker 16: I know that's why I spent my whole week composing

913
00:46:05,239 --> 00:46:08,280
Speaker 16: a haikup for the occasion. It's about my emotional journey

914
00:46:08,280 --> 00:46:11,839
Speaker 16: in podcasting over the last seven years, and it's called Earthquake.

915
00:46:11,280 --> 00:46:12,240
Speaker 15: House, Mega Mango.

916
00:46:12,520 --> 00:46:14,319
Speaker 2: I'm going to cut you off right there. Why don't

917
00:46:14,360 --> 00:46:16,000
Speaker 2: we just tell people about our show instead?

918
00:46:16,160 --> 00:46:18,839
Speaker 16: Yeah, that's a better idea. So every week on Part

919
00:46:18,840 --> 00:46:21,680
Speaker 16: Time Genius, we feed our curiosity by answering the world's

920
00:46:21,760 --> 00:46:25,480
Speaker 16: most important questions, things like when did America start dialing

921
00:46:25,560 --> 00:46:28,759
Speaker 16: nine to one? One? Is William Shatner's best acting work

922
00:46:28,840 --> 00:46:29,839
Speaker 16: in Esperanto?

923
00:46:30,280 --> 00:46:30,600
Speaker 1: Also?

924
00:46:31,040 --> 00:46:34,239
Speaker 15: What happened to Esperanto? Plus we cover questions like how

925
00:46:34,360 --> 00:46:37,439
Speaker 15: Chinese is your Chinese food? How do dollar stores stay

926
00:46:37,440 --> 00:46:41,000
Speaker 15: in business? And of course is there an Illuminati of cheese?

927
00:46:41,080 --> 00:46:44,319
Speaker 16: There absolutely is, and we are risking our lives by

928
00:46:44,320 --> 00:46:47,000
Speaker 16: talking about it. But if you love mind blowing facts,

929
00:46:47,040 --> 00:46:50,520
Speaker 16: incredible history and really bad jokes, make your brains happy

930
00:46:50,560 --> 00:46:52,160
Speaker 16: and tune into Part Time Genius.

931
00:46:52,520 --> 00:46:55,000
Speaker 15: Listen to Part Time Genius on the iHeartRadio app or

932
00:46:55,000 --> 00:46:56,440
Speaker 15: wherever you get your podcasts.

933
00:47:05,560 --> 00:47:08,040
Speaker 4: All right, Daniel, my favorite question in all these topics

934
00:47:08,200 --> 00:47:09,120
Speaker 4: what does it all mean?

935
00:47:10,000 --> 00:47:10,440
Speaker 1: Man?

936
00:47:10,920 --> 00:47:15,560
Speaker 4: So anything with gravity bends space around it, which cosses acceleration,

937
00:47:15,760 --> 00:47:19,200
Speaker 4: and accelerating things slowed down in time. So things are

938
00:47:19,239 --> 00:47:21,759
Speaker 4: always slowing down in time everywhere, all the time.

939
00:47:21,880 --> 00:47:26,160
Speaker 1: Yeah, everywhere there's a gravitational field, clocks are being slowed.

940
00:47:26,239 --> 00:47:28,400
Speaker 1: So if you're in a gravitational field, then your sense

941
00:47:28,440 --> 00:47:32,919
Speaker 1: of now is moving forward differently than other people who

942
00:47:32,920 --> 00:47:35,480
Speaker 1: are like out in deep space. And so if you

943
00:47:35,520 --> 00:47:38,560
Speaker 1: spend a lot of time near gravitational objects, then you

944
00:47:38,640 --> 00:47:41,520
Speaker 1: are younger than you otherwise would be right.

945
00:47:41,400 --> 00:47:43,279
Speaker 4: But it's not just gravity too, right. It's like if

946
00:47:43,280 --> 00:47:45,000
Speaker 4: I get in my car and I accelerate up to

947
00:47:45,000 --> 00:47:48,200
Speaker 4: the freeway, I somehow slow down time for myself.

948
00:47:48,600 --> 00:47:52,319
Speaker 1: Yeah, gravity and acceleration, they're equivalent, and so both of

949
00:47:52,320 --> 00:47:55,440
Speaker 1: them will slow down time. Every time you accelerate, the

950
00:47:55,600 --> 00:47:59,120
Speaker 1: universe sort of leaps forward a little bit relative to you.

951
00:47:59,320 --> 00:48:01,279
Speaker 1: If you accelerate rated a lot for a long time,

952
00:48:01,440 --> 00:48:04,480
Speaker 1: you would notice clocks around you seeming to move forward

953
00:48:04,560 --> 00:48:07,360
Speaker 1: faster than one second per second on your clock.

954
00:48:07,480 --> 00:48:09,080
Speaker 4: And so I guess that means first of all, that

955
00:48:09,120 --> 00:48:12,960
Speaker 4: there's no real age to the universe. Is that really true? That?

956
00:48:13,040 --> 00:48:16,520
Speaker 4: Does that mean that you know there's no like absolute time.

957
00:48:16,640 --> 00:48:19,520
Speaker 1: Yeah, there's no absolute time, which is really frustrating if

958
00:48:19,520 --> 00:48:22,080
Speaker 1: you'd like to have a sense that you know, there's truth,

959
00:48:22,200 --> 00:48:25,000
Speaker 1: that there's something really going on out there outside of

960
00:48:25,000 --> 00:48:28,360
Speaker 1: our skulls. It's frustrating to imagine that. Like, different people

961
00:48:28,360 --> 00:48:31,160
Speaker 1: can tell different stories and they can both be correct.

962
00:48:31,440 --> 00:48:33,440
Speaker 1: But there's an even deeper problem if you try to

963
00:48:33,480 --> 00:48:36,759
Speaker 1: extrapolate back to time equals zero. You know, we say

964
00:48:36,800 --> 00:48:40,319
Speaker 1: this thing the universe is thirteen point eight billion years old. Well,

965
00:48:40,440 --> 00:48:43,160
Speaker 1: according to what clock, right, has that clock been moving

966
00:48:43,160 --> 00:48:45,120
Speaker 1: on in spaceship? Has that clock spent a lot of

967
00:48:45,160 --> 00:48:47,480
Speaker 1: time near a black hole? Because if so, it's going

968
00:48:47,520 --> 00:48:50,080
Speaker 1: to have a different answer. And so, because different parts

969
00:48:50,080 --> 00:48:53,080
Speaker 1: of the universe have different curvature, right like near black

970
00:48:53,080 --> 00:48:55,920
Speaker 1: holes or near suns or whatever, then different parts of

971
00:48:55,920 --> 00:48:59,880
Speaker 1: the universe have aged differently since its beginning. So the

972
00:49:00,120 --> 00:49:03,120
Speaker 1: universe does not have one single age. Just like your

973
00:49:03,160 --> 00:49:06,480
Speaker 1: feet and your head are not the same age, assuming

974
00:49:06,600 --> 00:49:08,800
Speaker 1: you haven't spent your whole life in bed, the parts

975
00:49:08,800 --> 00:49:10,360
Speaker 1: of the universe have different ages.

976
00:49:10,440 --> 00:49:12,920
Speaker 4: I do a lot of handstands, so I'm trying not

977
00:49:12,960 --> 00:49:14,600
Speaker 4: to go bald, so I'm keeping my head.

978
00:49:14,680 --> 00:49:16,439
Speaker 1: I think we all need a video of you doing

979
00:49:16,440 --> 00:49:17,759
Speaker 1: a handstand. Let's see that.

980
00:49:19,000 --> 00:49:22,319
Speaker 4: That's good. But I guess that confuses me because you

981
00:49:22,360 --> 00:49:25,600
Speaker 4: told me earlier that acceleration is absolute, so I can

982
00:49:25,680 --> 00:49:31,719
Speaker 4: measure acceleration absolutely, and time is actually bent by acceleoration.

983
00:49:31,920 --> 00:49:34,360
Speaker 4: So couldn't I, I don't know, finest spot in the

984
00:49:34,440 --> 00:49:38,360
Speaker 4: universe that's never been accelerated and say that, like, that's

985
00:49:38,480 --> 00:49:40,480
Speaker 4: the absolute age of the universe.

986
00:49:40,520 --> 00:49:42,680
Speaker 1: Well, that's the age of that part of the universe,

987
00:49:42,719 --> 00:49:45,400
Speaker 1: and that would be the oldest part of the universe.

988
00:49:45,400 --> 00:49:48,719
Speaker 1: That part would have experienced the most time. But you know,

989
00:49:48,719 --> 00:49:50,719
Speaker 1: if you had put a clock somewhere else in the

990
00:49:50,800 --> 00:49:53,959
Speaker 1: universe and let it run since the beginning, it would

991
00:49:53,960 --> 00:49:56,360
Speaker 1: have a different number. So like different parts of the

992
00:49:56,440 --> 00:49:59,959
Speaker 1: universe have different ages, and you might reasonably say, well,

993
00:50:00,200 --> 00:50:02,160
Speaker 1: the oldest part of the universe, I'm gonna use that

994
00:50:02,320 --> 00:50:03,840
Speaker 1: as the age of the universe.

995
00:50:03,960 --> 00:50:06,480
Speaker 4: Yeah, nobody cares how young my feet are, you know,

996
00:50:07,000 --> 00:50:09,959
Speaker 4: I care, man, I care if you care.

997
00:50:10,160 --> 00:50:11,840
Speaker 1: It sounded a lot like I care though, right. That

998
00:50:11,880 --> 00:50:13,080
Speaker 1: sounded sincere, isn't it.

999
00:50:13,960 --> 00:50:16,239
Speaker 4: But yeah, so there's sort of an age limit to

1000
00:50:16,280 --> 00:50:18,799
Speaker 4: the universe, right, Like you're saying that there is an

1001
00:50:18,840 --> 00:50:21,640
Speaker 4: absolute age of the universe by which we can measure

1002
00:50:21,719 --> 00:50:22,640
Speaker 4: all other ages.

1003
00:50:22,760 --> 00:50:25,840
Speaker 1: Yeah, there's a maximum age to the universe, right, there

1004
00:50:26,000 --> 00:50:28,720
Speaker 1: is a number beyond which no part of the universe

1005
00:50:28,719 --> 00:50:31,759
Speaker 1: could have experienced more time than that. And if you

1006
00:50:31,760 --> 00:50:34,560
Speaker 1: wanted to find that as the age of the whole universe,

1007
00:50:34,719 --> 00:50:36,800
Speaker 1: I guess that makes sense. But I think more conceptually

1008
00:50:36,800 --> 00:50:39,200
Speaker 1: it makes sense to imagine like how many clock ticks

1009
00:50:39,239 --> 00:50:41,160
Speaker 1: have there been in a given part of the universe,

1010
00:50:41,480 --> 00:50:44,440
Speaker 1: And that's not equal all over the universe. It depends

1011
00:50:44,520 --> 00:50:47,240
Speaker 1: on how much gravity there is nearby.

1012
00:50:47,040 --> 00:50:49,399
Speaker 4: Right, Because I guess even our solar system is being

1013
00:50:49,440 --> 00:50:52,560
Speaker 4: accelerated around the Milky Way, so therefore our time is

1014
00:50:52,680 --> 00:50:54,680
Speaker 4: sort of being slowed down in that way too.

1015
00:50:54,800 --> 00:50:57,759
Speaker 1: Yeah, the curvature of the center of the Milky Way

1016
00:50:57,760 --> 00:51:00,600
Speaker 1: and that super massive black hole does a the motion

1017
00:51:00,719 --> 00:51:03,120
Speaker 1: of the Sun and the curvature nearby, which slows down

1018
00:51:03,239 --> 00:51:03,760
Speaker 1: our time.

1019
00:51:03,960 --> 00:51:05,840
Speaker 4: And I guess you were trying to tell me earlier

1020
00:51:05,880 --> 00:51:09,000
Speaker 4: that there is sort of a philosophical question here, which

1021
00:51:09,080 --> 00:51:17,759
Speaker 4: is like, does acceleration change time or does time change acceleration.

1022
00:51:17,880 --> 00:51:20,920
Speaker 1: Yeah, it's familiar to think about general relativity as saying

1023
00:51:21,520 --> 00:51:25,759
Speaker 1: that mass causes space to bend, and then the curvature

1024
00:51:25,800 --> 00:51:28,719
Speaker 1: of space tells masses how to move. Right that you

1025
00:51:28,760 --> 00:51:32,600
Speaker 1: get an appearance of acceleration, this effective force of gravity

1026
00:51:32,640 --> 00:51:36,680
Speaker 1: because space itself is bent. There's a missing component there, right,

1027
00:51:36,760 --> 00:51:39,960
Speaker 1: which is that time is also curved by mass, So

1028
00:51:40,080 --> 00:51:43,120
Speaker 1: you have masks somewhere. It doesn't just curve space, It

1029
00:51:43,160 --> 00:51:45,720
Speaker 1: also curves time, which is what we've been talking about today,

1030
00:51:45,840 --> 00:51:49,760
Speaker 1: and the curving of time also contributes to this force

1031
00:51:49,800 --> 00:51:52,760
Speaker 1: of gravity. So gravity is an apparent force that comes

1032
00:51:52,760 --> 00:51:55,200
Speaker 1: not just from the bending of space, but also from

1033
00:51:55,320 --> 00:51:58,280
Speaker 1: the bending of time. The two work together because space

1034
00:51:58,320 --> 00:52:01,120
Speaker 1: time really is sort of one thing to create this

1035
00:52:01,239 --> 00:52:02,759
Speaker 1: effect of gravity.

1036
00:52:02,920 --> 00:52:05,279
Speaker 4: You're saying time, you can also bend time, just like

1037
00:52:05,400 --> 00:52:10,000
Speaker 4: you can bend space, and somehow that's where gravity comes from.

1038
00:52:10,080 --> 00:52:13,360
Speaker 1: Yeah, exactly. It's familiar to use like a rubber sheet analogy,

1039
00:52:13,719 --> 00:52:15,920
Speaker 1: where parts of space are bent and that changes how

1040
00:52:15,960 --> 00:52:18,640
Speaker 1: an object moves sort of naturally. And you know, that's

1041
00:52:18,640 --> 00:52:21,400
Speaker 1: a little confusing because in what direction is the rubber

1042
00:52:21,440 --> 00:52:24,320
Speaker 1: sheet bending. It's bending in some sort of like external direction.

1043
00:52:24,840 --> 00:52:27,000
Speaker 1: You can measure it in terms of like another dimension

1044
00:52:27,120 --> 00:52:30,440
Speaker 1: in reality in our space. It's intrinsic curvature. It just

1045
00:52:30,560 --> 00:52:34,400
Speaker 1: changes the relationship between points in space their relative distances.

1046
00:52:34,600 --> 00:52:36,920
Speaker 1: So that's a familiar way to think about how the

1047
00:52:37,000 --> 00:52:40,360
Speaker 1: curvature of space affects the motion of an object. You

1048
00:52:40,400 --> 00:52:42,680
Speaker 1: can do something similar for a time. You can imagine

1049
00:52:42,719 --> 00:52:46,239
Speaker 1: like different parts of the universe flowing with different time. Right,

1050
00:52:46,239 --> 00:52:48,680
Speaker 1: It's sort of like you're moving down a river and

1051
00:52:48,800 --> 00:52:51,320
Speaker 1: different parts of the river are moving faster than others,

1052
00:52:51,640 --> 00:52:54,120
Speaker 1: and that will affect the motion of objects. Like you

1053
00:52:54,160 --> 00:52:56,520
Speaker 1: have a really big object in a river and the

1054
00:52:56,640 --> 00:52:58,520
Speaker 1: river is flowing faster on the left side than on

1055
00:52:58,560 --> 00:53:00,600
Speaker 1: the right side. It's going to change change the way

1056
00:53:00,600 --> 00:53:03,880
Speaker 1: that object moves. It'll like tug it towards the slow

1057
00:53:03,960 --> 00:53:07,280
Speaker 1: moving part of the river. And that's part of how

1058
00:53:07,440 --> 00:53:10,960
Speaker 1: the curvature of space and time creates this effect of

1059
00:53:11,000 --> 00:53:13,800
Speaker 1: gravity that objects no longer move and what we perceive

1060
00:53:13,880 --> 00:53:14,960
Speaker 1: to be straight lines.

1061
00:53:15,120 --> 00:53:16,680
Speaker 4: I see you're saying, like you can think of it

1062
00:53:16,719 --> 00:53:19,400
Speaker 4: the other way around, like me falling to the Earth

1063
00:53:19,840 --> 00:53:22,400
Speaker 4: or me being in orbit around the Earth is actually

1064
00:53:22,480 --> 00:53:26,440
Speaker 4: a consequence of the differences in time, and like differences

1065
00:53:26,480 --> 00:53:29,120
Speaker 4: in time caused me to move from one place to another.

1066
00:53:28,960 --> 00:53:33,879
Speaker 1: Exactly it's space and time being curved both affect your trajectory.

1067
00:53:34,120 --> 00:53:37,000
Speaker 4: Cool, So in a way, asking why does gravity slow

1068
00:53:37,080 --> 00:53:40,400
Speaker 4: down time, you could also mainly ask why does time

1069
00:53:41,160 --> 00:53:42,760
Speaker 4: slowing down time cause gravity?

1070
00:53:42,840 --> 00:53:45,080
Speaker 1: Yeah, exactly. Another way to think about it is that

1071
00:53:45,120 --> 00:53:48,160
Speaker 1: the effect of gravity we observe is coming from the

1072
00:53:48,160 --> 00:53:50,560
Speaker 1: curvature of space and the curvature of time, and that

1073
00:53:50,760 --> 00:53:54,760
Speaker 1: gravitational time dilation is just another aspect of the curving

1074
00:53:54,960 --> 00:53:57,160
Speaker 1: of space time in respect to mass.

1075
00:53:57,280 --> 00:53:58,680
Speaker 4: So I guess in the end, you just have to

1076
00:53:58,719 --> 00:54:01,720
Speaker 4: say that it's all of kind of the same thing.

1077
00:54:02,040 --> 00:54:04,239
Speaker 4: It's all sort of related, and it's all you know.

1078
00:54:04,280 --> 00:54:06,600
Speaker 4: You can look at it from one player, you can

1079
00:54:06,640 --> 00:54:08,320
Speaker 4: look at it upside down, But at the end of

1080
00:54:08,360 --> 00:54:11,759
Speaker 4: the day, it all comes down to really, I think acceleration, right,

1081
00:54:11,880 --> 00:54:14,759
Speaker 4: Like things that accelerate have to slow down in time

1082
00:54:14,840 --> 00:54:17,040
Speaker 4: because of the speed limit of the universe.

1083
00:54:17,200 --> 00:54:19,160
Speaker 1: Yeah, that's a consistent way to think about it. I

1084
00:54:19,239 --> 00:54:21,319
Speaker 1: prefer the sort of geometrical way to think about it,

1085
00:54:21,320 --> 00:54:23,640
Speaker 1: that we're living in a universe that's courage and warp

1086
00:54:23,719 --> 00:54:26,120
Speaker 1: but we don't perceive it directly, and so the way

1087
00:54:26,160 --> 00:54:29,399
Speaker 1: things move through space and time are affected by these

1088
00:54:29,440 --> 00:54:32,600
Speaker 1: like invisible warping. That sort of geometrically makes the most

1089
00:54:32,600 --> 00:54:34,120
Speaker 1: sense to me. But you can also think about it

1090
00:54:34,160 --> 00:54:36,720
Speaker 1: just in terms of acceleration in flat space.

1091
00:54:36,800 --> 00:54:39,040
Speaker 4: Yeah, all right, well, I guess that answers sort of

1092
00:54:39,040 --> 00:54:41,800
Speaker 4: the question why does gravity slow down time? The answer

1093
00:54:41,960 --> 00:54:46,120
Speaker 4: is because of acceleration, And why does acceleration slow down time? Well,

1094
00:54:46,200 --> 00:54:48,759
Speaker 4: we probably need a whole new podcast episode about it.

1095
00:54:48,840 --> 00:54:51,279
Speaker 1: Yeah, why does gravity slow down time? Because time is

1096
00:54:51,320 --> 00:54:53,960
Speaker 1: bent in the presence of mass, just like spaces.

1097
00:54:55,000 --> 00:54:59,319
Speaker 4: I think you just went all the way around. Why

1098
00:54:59,360 --> 00:55:02,280
Speaker 4: does accele slow in time? Because slowing down time causes excelation.

1099
00:55:03,000 --> 00:55:04,439
Speaker 4: Sounds like a great answer.

1100
00:55:04,360 --> 00:55:06,440
Speaker 1: And it causes podcasts to go in circles.

1101
00:55:06,560 --> 00:55:09,560
Speaker 4: Yeah, now you could just hit replay and listen to

1102
00:55:09,600 --> 00:55:12,120
Speaker 4: this episode all over again and it should make sense.

1103
00:55:12,200 --> 00:55:14,160
Speaker 1: Right. It's all pretty tricky stuff, and the end it

1104
00:55:14,160 --> 00:55:17,680
Speaker 1: all comes down to consequences from our observation that the

1105
00:55:17,719 --> 00:55:20,080
Speaker 1: speed of light is the maximum speed of the universe

1106
00:55:20,120 --> 00:55:22,239
Speaker 1: that just happens to be the universe we live in,

1107
00:55:22,320 --> 00:55:24,760
Speaker 1: and when we build in those constraints into our theories,

1108
00:55:24,960 --> 00:55:27,040
Speaker 1: these are all the consequences that come out of it.

1109
00:55:27,080 --> 00:55:29,040
Speaker 4: And maybe that points to what you were saying earlier

1110
00:55:29,080 --> 00:55:32,080
Speaker 4: that you know, we have this speed limit and it

1111
00:55:32,160 --> 00:55:34,880
Speaker 4: causes time to do weird things. So maybe time is

1112
00:55:34,920 --> 00:55:37,520
Speaker 4: not a fundamental thing, right, Like it's not outside of

1113
00:55:37,520 --> 00:55:41,440
Speaker 4: the universe. Maybe time is something that comes out of

1114
00:55:41,520 --> 00:55:42,680
Speaker 4: how the universe.

1115
00:55:42,360 --> 00:55:45,480
Speaker 1: Works, yeah, or how we are perceiving it or measuring it.

1116
00:55:45,800 --> 00:55:48,560
Speaker 1: And you know, there's a whole universe of crazy ideas

1117
00:55:48,600 --> 00:55:51,440
Speaker 1: about time, even ideas that like time is not an

1118
00:55:51,480 --> 00:55:53,640
Speaker 1: essential part of the universe but comes out of something else,

1119
00:55:53,760 --> 00:55:56,839
Speaker 1: or that there are multiple dimensions of time, the way

1120
00:55:56,880 --> 00:56:00,160
Speaker 1: there are multiple dimensions of space and we're just moving

1121
00:56:00,200 --> 00:56:04,200
Speaker 1: on like a one D line through three dimensional time. Man,

1122
00:56:04,760 --> 00:56:08,200
Speaker 1: there's a whole like crazy, crazy set of really fun

1123
00:56:08,239 --> 00:56:09,080
Speaker 1: ideas to dig into.

1124
00:56:09,280 --> 00:56:12,439
Speaker 4: Unfortunately we are out of time for this episode. We'll

1125
00:56:12,480 --> 00:56:14,960
Speaker 4: have to find more time to get into it more.

1126
00:56:15,000 --> 00:56:17,400
Speaker 4: But we hope you enjoyed that and maybe got you

1127
00:56:17,480 --> 00:56:20,279
Speaker 4: to think a little bit more about how young your

1128
00:56:20,320 --> 00:56:22,839
Speaker 4: feet are and how you should maybe do more handstand.

1129
00:56:22,600 --> 00:56:24,400
Speaker 1: I want to see that video if you're doing a handstand.

1130
00:56:25,480 --> 00:56:27,640
Speaker 4: I can't do it actually, but now it's not the time,

1131
00:56:27,719 --> 00:56:30,560
Speaker 4: all right, Well, thanks for joining us, see you next time.

1132
00:56:38,320 --> 00:56:41,120
Speaker 1: Thanks for listening. And remember that Daniel and Jorge Explain

1133
00:56:41,200 --> 00:56:44,479
Speaker 1: the Universe is a production of iHeart Radio. For more

1134
00:56:44,520 --> 00:56:49,160
Speaker 1: podcasts from iHeart Radio, visit the iHeartRadio app, Apple Podcasts,

1135
00:56:49,280 --> 00:57:03,319
Speaker 1: or wherever you listen to your favorite shows. When you

1136
00:57:03,320 --> 00:57:05,400
Speaker 1: pop a piece of cheese into your mouth, you're probably

1137
00:57:05,440 --> 00:57:08,480
Speaker 1: not thinking about the environmental impact. But the people in

1138
00:57:08,520 --> 00:57:11,640
Speaker 1: the dairy industry are. That's why they're working hard every

1139
00:57:11,719 --> 00:57:15,040
Speaker 1: day to find new ways to reduce waste, conserve natural resources,

1140
00:57:15,080 --> 00:57:18,640
Speaker 1: and drive down greenhouse gas emissions. How is us dairy

1141
00:57:18,680 --> 00:57:22,760
Speaker 1: tackling greenhouse gases? Many farms use anaerobic digestors to turn

1142
00:57:22,840 --> 00:57:27,360
Speaker 1: the methane from manure into renewable energy that can power farms, towns,

1143
00:57:27,360 --> 00:57:30,640
Speaker 1: and electric cars. Visit you as dairy dot COM's Last

1144
00:57:30,680 --> 00:57:32,280
Speaker 1: Sustainability to learn more.

1145
00:57:33,040 --> 00:57:34,160
Speaker 2: Guess what Well, what's that?

1146
00:57:34,240 --> 00:57:34,520
Speaker 14: Mago?

1147
00:57:34,840 --> 00:57:36,840
Speaker 16: I've been trying to write a promo for our podcast,

1148
00:57:36,880 --> 00:57:39,400
Speaker 16: Part Time Genius, but even though we've done over two

1149
00:57:39,480 --> 00:57:42,360
Speaker 16: hundred and fifty episodes, we don't really talk about murders

1150
00:57:42,480 --> 00:57:43,120
Speaker 16: or cults.

1151
00:57:43,240 --> 00:57:45,680
Speaker 15: I mean, we did just cover the Illuminati of cheese,

1152
00:57:45,680 --> 00:57:47,880
Speaker 15: so I feel like that makes us pretty edgy. We

1153
00:57:47,920 --> 00:57:51,120
Speaker 15: also solve mysteries like how Chinese is your Chinese food?

1154
00:57:51,280 --> 00:57:53,960
Speaker 15: And how do dollar stores make money? And then of

1155
00:57:53,960 --> 00:57:56,040
Speaker 15: course can you game a dog show?

1156
00:57:56,320 --> 00:57:58,640
Speaker 16: So what you're saying is everyone should be listening.

1157
00:57:59,000 --> 00:58:01,360
Speaker 15: Listen to Part Time Genius on the iHeartRadio app or

1158
00:58:01,400 --> 00:58:02,840
Speaker 15: wherever you get your podcasts.

1159
00:58:03,840 --> 00:58:06,240
Speaker 13: Hi, everyone, it's me Katie Couric. You know, if you've

1160
00:58:06,280 --> 00:58:09,040
Speaker 13: been following me on social media, you know I love

1161
00:58:09,080 --> 00:58:12,240
Speaker 13: to cook, or at least try, especially alongside some of

1162
00:58:12,280 --> 00:58:16,000
Speaker 13: my favorite chefs and foodies like Benny Blanco, Jake Cohen,

1163
00:58:16,080 --> 00:58:20,520
Speaker 13: Lighty Hoyke, Alison Roman, and Ininagarten. So I started a

1164
00:58:20,520 --> 00:58:24,120
Speaker 13: free newsletter called Good Taste to share recipes, tips and

1165
00:58:24,240 --> 00:58:28,400
Speaker 13: kitchen mustaves. Just sign up at Katiecuric dot com slash

1166
00:58:28,560 --> 00:58:31,520
Speaker 13: good Taste. That's k A t I E C O

1167
00:58:31,680 --> 00:58:35,320
Speaker 13: U r I c dot com slash good Taste. I

1168
00:58:35,440 --> 00:58:38,120
Speaker 13: promise your taste buds will be happy you did