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Speaker 1: Hey, Daniel, do you get a lot of emails claiming

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Speaker 1: that Einstein was wrong?

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Speaker 2: Oh? Yeah, just about every day I get an email

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Speaker 2: from some retired engineer who sends me there Einstein was

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Speaker 2: wrong paper.

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Speaker 1: Is that the stereotype they retired engineer who has a

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Speaker 1: lot of time in their hands.

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Speaker 2: Not just the stereotype, it's also the reality.

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Speaker 1: Do you not get emails from retired physicists? Also, physicists

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Speaker 1: don't retire. I guess they wouldn't asked you questions if

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Speaker 1: they were physicists.

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Speaker 2: Yeah, they would just publish the papers themselves.

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Speaker 1: Or physicists never retire. Maybe the only engineers are smart

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Speaker 1: enough never retire.

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Speaker 2: We just read eat away.

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Speaker 1: But do you read these emails or do you just

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Speaker 1: you know, send them to your trash box.

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Speaker 2: No. I give each of them like ten or fifteen minutes.

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Speaker 2: See maybe if they're onto something.

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Speaker 1: Oh well, ten to fifteen minutes, that's a that's a

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Speaker 1: pretty good amount. Do you do it because you think

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Speaker 1: they might? You're right?

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Speaker 2: Well, I believe in curiosity and maybe somebody out there

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Speaker 2: does have a great idea. I mean, their heart's in

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Speaker 2: the right place, even if usually the details are wrong.

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Speaker 1: So you do think they might be right.

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Speaker 2: Well, they're definitely right that Einstein was wrong. It just

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Speaker 2: so happens that so are most of these engineers.

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Speaker 1: Well, I guess that's wrong. Is Einstein is not a

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Speaker 1: bad title. I mean, if he couldn't get it right,

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Speaker 1: at least the engineers are trying.

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Speaker 2: Eventually, one of these engineers is going to figure it out.

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Speaker 1: But what if they figure it out on like the

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Speaker 1: sixteenth minute of their paper. Maybe you should double your

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Speaker 1: efforts until you retire.

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Speaker 2: There you go, that's going to retire me.

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Speaker 1: I am horeham May, cartoonists and the author of Oliver's

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Speaker 1: Great Big Universe.

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Speaker 2: Hi, I'm Daniel. I'm a particle physicist and a professor

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Speaker 2: at UC Irvine, and I want to be around when

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Speaker 2: we figure out how Einstein was wrong.

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Speaker 1: But you don't want to be the one who figures

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Speaker 1: it out? Do you just want to be around?

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Speaker 2: I just want to cling on to my tenured position

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Speaker 2: for long enough to be here for the party when

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Speaker 2: somebody else figures it out. Now, I'd love to figure

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Speaker 2: it out myself. I'm just not that egotistical.

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Speaker 1: Hmm. Do you think there'll be a big party when

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Speaker 1: they prove Einstein was wrong? Wouldn't that be sort of like,

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Speaker 1: you know, spinning on the grave of a great genius.

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Speaker 2: No, I think it was a tremendous accomplishment when Einstein

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Speaker 2: proved Newton wrong, and no shade on Newton. You know,

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Speaker 2: Newton made a huge advance, a big leap forward, just

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Speaker 2: not all the way to the final truth, and same

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Speaker 2: way its Einstein. And you know the history of physics

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Speaker 2: is littered with these pivotal moments when we made a

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Speaker 2: leap forward in understanding. And I want to be around

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Speaker 2: when we have one of those.

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Speaker 1: But do you think Eistein held a party like and

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Speaker 1: Newton was wrong?

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Speaker 2: Party was wrong party? I don't know if you put

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Speaker 2: it that way, you know, but when his theory of

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Speaker 2: john relativity was so publicly proven right by the eclipse

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Speaker 2: and the visible bending of light, I bet he had

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Speaker 2: a glass of champagne or something.

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Speaker 1: Or maybe he was, you know, nice enough not to

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Speaker 1: dis ut.

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Speaker 2: We're all standing on the shoulders of giants. We don't

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Speaker 2: have to denigrate those giants.

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Speaker 1: That's why you only like to stand under grave and dance.

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Speaker 1: But anyways, welcome to our podcast. Daniel and Jorge explain

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Speaker 1: the Universe, a production of iHeartRadio.

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Speaker 2: In which we try to climb onto the shoulders of

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Speaker 2: those giants with you to bring you along on this

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Speaker 2: fascinating journey the humans have been engaged in for thousands

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Speaker 2: of years to try to understand the nature of our universe.

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Speaker 2: Is there a single law that explains how everything works

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Speaker 2: out there? Is there a final truth for us to discover.

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Speaker 2: Are we on the path to deeply understanding the nature

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Speaker 2: of reality? Or is an endless quest, a long ladder

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Speaker 2: of improvements without ever actually reaching the truth.

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Speaker 1: That's right because as much as science has discovered about

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Speaker 1: the universe, about how how it all works, why it's

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Speaker 1: all made off, there's still a whole bunch of stuff

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Speaker 1: that we don't know about, big mysteries out during the

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Speaker 1: cosmos that we are still trying to figure out, and

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Speaker 1: that we have lots of ideas for. But sometimes those

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Speaker 1: ideas are not quite right.

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Speaker 2: Because science is a process, not a destination, and we

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Speaker 2: are continually updating, improving, and revising our theories for how

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Speaker 2: things work. We think we understand something, and then decad

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Speaker 2: later an engineer shows.

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Speaker 1: Us we were wrong, as is always the case.

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Speaker 2: But those are happy moments in science. Those are the

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Speaker 2: critical pivotal steps forward, those bring us closer to the truth.

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Speaker 2: We're not here to defend the ideas of the ancients,

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Speaker 2: to hold up Aristotilian physics for everybody to believe in,

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Speaker 2: but to bring ourselves closer to the truth by revising

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Speaker 2: the ideas of geniuses who have come before us.

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Speaker 1: Yeah. I feel like that's a very core principle of

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Speaker 1: science that makes it so special, is that there's always

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Speaker 1: the possibility that you could be wrong.

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Speaker 2: Yeah. In fact, probably everything we know about science is

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Speaker 2: wrong in some sense. Everything we do is some approximation

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Speaker 2: of the truth which we might never actually reach.

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Speaker 1: What do you mean, never reach? Are you giving up now?

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Speaker 2: I'm not giving up. I'm promising job security for future physicists.

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Speaker 2: I'm saying it's an infinite task.

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Speaker 1: You're saying, if you're a physicist, you're never going to retire,

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Speaker 1: So choose engineering if you want to at some point

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Speaker 1: stop working.

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Speaker 2: I'm just trying to be humble. You know, every idea

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Speaker 2: we've had in physics has eventually been supplanted by something

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Speaker 2: more precise, something we think is more deeply true. It'd

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Speaker 2: be really egotistical to say, well, the idea we have now,

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Speaker 2: now this is the one that's going to hold up forever.

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Speaker 1: Well, this has been going on for centuries and maybe

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Speaker 1: even thousands of years, and even big names like Einstein

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Speaker 1: people think might not be quite right.

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Speaker 2: Some of these theories we've developed are not just very

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Speaker 2: very accurate, they're beautiful. They give us deep insights into

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Speaker 2: how the universe might work. They tell us a story

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Speaker 2: about how the universe functions, sometimes in a way it's

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Speaker 2: very surprising and intuitive for us. So it's hard to believe.

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Speaker 2: But we think most of these theories might still be wrong.

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Speaker 1: So today on the podcast, we'll be tackling the question

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Speaker 1: how is general relativity wrong? Shouldn't mean to first talk

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Speaker 1: about how it's right.

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Speaker 2: We should, but I just.

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Speaker 1: Or is that what we've been doing for the last

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Speaker 1: five hundred episodes?

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Speaker 2: Yeah, the last one hundred years has been how general

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Speaker 2: relativity is right? But I was going to say, welcome

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Speaker 2: to the group of retired engineers, but then I realized,

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Speaker 2: are you a retired engineer? A? Right?

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Speaker 1: I am an engineer technically, I guess you don't lose

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Speaker 1: the title. Yeah, I'm not quite retired. I'm not sure

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Speaker 1: anyone would trust me to design a bridge or any

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Speaker 1: kind of a car or anything. Maybe a robot. Robots me,

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Speaker 1: what could go wrong.

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Speaker 2: With exactly, I've never read a story about robots.

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Speaker 1: Robots are totally safe. But yeah, I know. But I

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Speaker 1: look forward to to the day where I can, When

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Speaker 1: I can retire for sure, then I can send you questions.

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Speaker 2: You'll get your fifteen minutes, just like everybody.

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Speaker 1: Else, my fifteen minutes of physics. Yes, exactly, that's right,

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Speaker 1: most people along for fifteen minutes of fame. The entire

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Speaker 1: engineer is long for fifteen minutes of a physicist time.

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Speaker 1: But yeah, this is an interesting question to talk about.

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Speaker 1: How general relativity, which is I guess, the main theory

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Speaker 1: or one of the main theories that Einstein discovered, right, Yeah.

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Speaker 2: Einstein made lots of contributions to physics, even inspiring quantum

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Speaker 2: mechanics with his explanation of the photoelectric effect, which is

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Speaker 2: what he actually won the Nobel Prize for. But a

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Speaker 2: lot of people think that his greatest contribution to physics

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Speaker 2: really were the theories of special relativity and then general

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Speaker 2: relativity and tell us about how light operates, what space

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Speaker 2: time really is, and explain that gravity is not actually

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Speaker 2: a force, it's just a product of the curvature of

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Speaker 2: space and time.

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Speaker 1: I would have thought his greatest contribution was hair. Do

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Speaker 1: you know. I feel like it's so iconic in the culture,

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Speaker 1: and it's given permission to every physicist since then not

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Speaker 1: get a haircut.

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Speaker 2: But it's so effortless, right, that's the whole point of

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Speaker 2: his hair due is like, I don't even care what

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Speaker 2: he looks like up there. I don't I don't have

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Speaker 2: to look at it. You got to look at.

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Speaker 1: It, That's what I mean. That's what I mean. You

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Speaker 1: gave permission for the rest of you see, to give

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Speaker 1: all of the the other physicists standing on his shoulders

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Speaker 1: to just let it all hang out.

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Speaker 2: Well, you're standing on his shoulders. You got your head

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Speaker 2: stuck right in that hair. You know, you can't really.

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Speaker 1: Avoid it everywhere, that's right, Yeah, yeah, yeah, don't drop

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Speaker 1: a pan or anything, you might lose it in that hair. Well,

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Speaker 1: as usually, we were wondering how many people out there

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Speaker 1: had thought about the idea that Einstein might be wrong,

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Speaker 1: that general relativity is not quite right, and in which

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Speaker 1: way isn't it right?

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Speaker 2: So thanks very much to everybody who answers these questions.

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Speaker 2: If you would like to join our group of volunteers.

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Speaker 2: Please write to me two questions at Danielandjorge dot com.

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Speaker 2: We'd love to hear your voice.

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Speaker 1: But do you have to be a retired engineer to

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Speaker 1: join the group.

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Speaker 2: You can be a current engineer, you can be a

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Speaker 2: retired engineer, you can be an inspiring engineer, you can

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Speaker 2: be a chocolate engineer. Any kind of engineer is welcome,

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Speaker 2: even non engineers.

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Speaker 1: Well, think about it for a second. How do you

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Speaker 1: think general relativity might be wrong? Here's what people had

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Speaker 1: to say.

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Speaker 3: And I think general relativity is wrong or has to

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Speaker 3: be wrong because in its sort of proposition of singularity

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Speaker 3: in the middle of black holes, because that's just like impossible, right,

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Speaker 3: somehow that has got to be not true.

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Speaker 4: I'm I'm entirely sure how general relativity is wrong. It's

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Speaker 4: actually been something that's bothering me, so I'll be very

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Speaker 4: interested to hear. And I suspect it is quantum physics

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Speaker 4: that has disproved, So I'm not entirely sure how the.

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Speaker 5: Hi Daniel and Hawaii love your show. Keep up the

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Speaker 5: great I think the biggest thing that seems off with

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Speaker 5: general relativity to me is the idea that there is

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Speaker 5: an infinity. If you think about other concepts like absolute zero,

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Speaker 5: there's reasons in real life why we can't reach that temperature.

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Speaker 5: And I think if we can understand what those reasons

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Speaker 5: are for black holes, for example, then maybe we'll be

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Speaker 5: able to understand what the problem is with general relativity.

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Speaker 6: Well, it doesn't account for quantum physics and quantum particles,

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Speaker 6: and I think with how the Big Bang started, it

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Speaker 6: doesn't count for the very initial moments after the Big

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Speaker 6: Bang because that includes quantum particles.

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Speaker 1: All Right, I feel like maybe we've talked about this

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Speaker 1: enough in our podcast, yet people seem pretty familiar with

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Speaker 1: this idea.

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Speaker 2: Yeah. I think we've been sort of gent nagging general

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Speaker 2: relativity for a while now.

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Speaker 1: If people have some clues where we're trying to seduce

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Speaker 1: general relativity here, what's your plan here?

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Speaker 2: No, we've been sort of warming people up to the

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Speaker 2: idea that maybe general relativity isn't telling us the truth

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Speaker 2: about nature.

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Speaker 1: Well, let's dig into Daniel. First of all, what is

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Speaker 1: general relativity and how is it different than other kinds

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Speaker 1: of relativity.

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Speaker 2: So Einstein's first theory of relativity was special relativity, and

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Speaker 2: this was in response to weird mysteries about the speed

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Speaker 2: of light, the Michaelson Morley experiment, electromagnetism and frame dependence

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Speaker 2: and all that stuff. And the theory of special relativity

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Speaker 2: is the one that tells us that light moves at

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Speaker 2: the same speed for all observers, and it leads us

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Speaker 2: to understand how time flows and how events can be

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Speaker 2: simultaneous for one person and not simultaneous for another, and

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Speaker 2: things get shorter at high speeds, and there's a maximum

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Speaker 2: speed at which things could travel. That's all the fascinating

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Speaker 2: physics of space relativity, which already was like a huge

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Speaker 2: brain twist for people back then, right, it was very

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Speaker 2: hard to accept very new idea for how the universe worked.

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Speaker 2: That was special relativity.

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Speaker 1: But is it called special relativity? What is it special

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Speaker 1: from or about?

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Speaker 2: Because it's only relevant in one particular circumstance, and that's

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Speaker 2: when you assume that space is flat, that space has

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Speaker 2: no curvature to it. General relativity is his generalization of

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Speaker 2: special relativity to much broader set of cases, scenarios where

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Speaker 2: the universe has big lumps of mass in it and

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Speaker 2: that mass curves space. Instead of thinking about light pulses

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Speaker 2: moving through space in straight lines and staying parallel to

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Speaker 2: each other. Now, he developed the mathematics to consider what

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Speaker 2: happened when space itself was curved, when light moved in

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Speaker 2: what seemed like curved paths.

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Speaker 1: But did he call it special relativity when he came

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Speaker 1: up with it? Like, did he know as a special

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Speaker 1: case and maybe it wouldn't didn't apply to the rest

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Speaker 1: of the universe.

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Speaker 5: Mm hmm.

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Speaker 2: I'm sure some of our German listeners will know how

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Speaker 2: to say it in German, because these original papers, of course,

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Speaker 2: were not in English. But yeah, he originally called it

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Speaker 2: special relativity and then general relativity.

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Speaker 1: But does that mean then that special relativity is automatically

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Speaker 1: wrong because it only works when space is flat. But

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Speaker 1: space is never flat, is it. Yeah, that's a great question,

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Speaker 1: and it sort of begs the philosophical question what do

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Speaker 1: we mean by wrong? Because the universe is never totally empty.

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Speaker 1: Space is always a little bit curved here, a little

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Speaker 1: bit curved there. I mean, even if you just have

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Speaker 1: a photon passing through space, that is curving space itself, right,

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Speaker 1: because photons have energy. So in that sense, special relativity

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Speaker 1: is approximately right. It's never deeply truly right because it

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Speaker 1: doesn't describe our universe.

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Speaker 2: That doesn't mean the rules of special relativity are wrong, right.

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Speaker 2: It could be that the rules of special relativity are correct,

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Speaker 2: they're just never applicable because the situation describes an energy

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Speaker 2: less universe never actually arises.

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Speaker 1: Wait, so special relativity sort of only works in a

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Speaker 1: new tone in kind of universe. Like you have to

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Speaker 1: assume that Newton was right first.

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Speaker 2: Well, no, Newton had a different theory of space and time.

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Speaker 2: He thought that space and time were absolute backdrops that

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Speaker 2: you could like measure your velocity relative to space, that

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Speaker 2: space was this like stage upon which everything happened. Special

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Speaker 2: relativity already tells you that things like velocity are relative.

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Speaker 2: There is no absolute frame of reference to the universe.

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Speaker 2: So even special relativity is a big departure from Newton's

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Speaker 2: view of how the universe worked.

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Speaker 1: But it sort of also assumed that, like a giant universe,

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Speaker 1: it is not vendable, that's like fixed, kind.

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Speaker 2: Of in the same sense that Newton assumed that, like

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Speaker 2: the X axis runs perfectly straight out to infinity. Special

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Speaker 2: relativity also assumes that.

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Speaker 1: Okay, So then did Einstein know that he had relativity

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Speaker 1: in his boget when he came up with special relativity

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Speaker 1: or was it like a progression of theories.

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Speaker 2: It was definitely a progression. He had not yet solved

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Speaker 2: general relativity. This is not like a staged release where

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Speaker 2: he's like, I got big idea, but I got to

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Speaker 2: like drip it out to the public.

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Speaker 1: This is not like a poor camp But he sort

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Speaker 1: of knew that he special or if he called it

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Speaker 1: special relativity, he knew that only applied to a special case.

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Speaker 2: Yeah, but he hadn't solved the general case yet. It

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Speaker 2: took him years and years to figure it out because

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Speaker 2: the mathematics was super hairy, and he relied on like

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Speaker 2: clever ideas from other mathematical geniuses that he talked to

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Speaker 2: to make his theory of general relativity work. And it's

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Speaker 2: still famously almost impossible to deal with. Like, the equations

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Speaker 2: of general relativity are so complicated, we mostly can't even

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Speaker 2: solve them for anything that looks like our universe. Like

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Speaker 2: we've solved general relativity for scenarios like the universe is

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Speaker 2: filled smoothly with mass, where the universe has nothing in

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Speaker 2: it but a black hole, we can't exactly solve the

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Speaker 2: equations of general relativity for any realistic scenarios because they're

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Speaker 2: so hairy. So it took Einstein years to come up

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Speaker 2: with his theory.

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Speaker 5: Mm.

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Speaker 1: But I guess maybe my question is, like, when he

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Speaker 1: came up with special relativity, did he know that space

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Speaker 1: could actually bend and that the universe actually very different

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Speaker 1: or did that come about when he discovered general relativity.

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Speaker 2: Now, he had that idea that he wanted to incorporate

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Speaker 2: curvature into the fabric of space time as a way

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Speaker 2: to explain gravity. He just hadn't figured out how to

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Speaker 2: make the mathematics of it all work, and that took

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Speaker 2: years and sort of novel mathematics at the time. You know,

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Speaker 2: differential geometry, the idea of like thinking about how things

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Speaker 2: move along curve services. That was kind of new stuff

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Speaker 2: one hundred years ago.

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Speaker 1: All right, well, maybe break it down for us, How

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Speaker 1: would you explain what general relativity is.

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Speaker 2: General relativity is an explanation for why we think there's

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Speaker 2: a force of gravity. It tells us that as things

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Speaker 2: move through space, it's not as Newton described, that they

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Speaker 2: have mass and that mass gives them a force that

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Speaker 2: attract each other, but instead that mass bends space and

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Speaker 2: then they move according to the curvature of that space.

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Speaker 2: So when you jump off a building and you fall

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Speaker 2: towards the Earth, it's not that the Earth's gravity is

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Speaker 2: pulling on you, accelerating you towards the center of the Earth.

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Speaker 2: But now you're moving according to the curvature of space.

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Speaker 2: The Earth has bent space, and you're moving along that

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Speaker 2: curvature towards the center of the Earth. So it's a

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Speaker 2: different picture.

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Speaker 1: And I guess you mean space time right, because you

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Speaker 1: have to kind of mix time into it, right, because

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Speaker 1: like something the bowling belt doesn't fall towards the Earth

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Speaker 1: like it needs time to do that.

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Speaker 2: Right. Time is definitely important factor. And special relativity already

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Speaker 2: showed us that space and time are very closely connected

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Speaker 2: and actually linked them together into four dimensional object. And

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Speaker 2: in that sort of four dimensional way of thinking, a

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Speaker 2: lot of things that didn't make sense in three D

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Speaker 2: space and one D time now click together to make

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Speaker 2: these really beautiful symmetries that you just don't have if

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Speaker 2: you think about space and time separately. The same way

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Speaker 2: that like linking electricity and magnetism together into one object

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Speaker 2: explains a lot of mysteries between them, linking space and

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Speaker 2: time together into one object really makes the mathematics crisp

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Speaker 2: and clear and beautiful, so you have special relativity is

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Speaker 2: based on the idea that space and time, and general

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Speaker 2: relativity just expands that. So absolutely space time is curved,

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Speaker 2: and general relativity also predicts the distortion of time. As

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Speaker 2: things pass through curvature, their time ticks more slowly. General

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Speaker 2: relativity describes the curvature of space time.

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Speaker 1: But the way you're describing it is sort of like

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Speaker 1: it's all about gravity.

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Speaker 2: Gravity comes out as a consequence of this story. Really,

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Speaker 2: what we're trying to do is describe the nature of reality,

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Speaker 2: like what's out there? Why do things move the way

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Speaker 2: we see them moving? If you're in a spaceship and

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Speaker 2: you're looking at the Earth orbiting the sull and you

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Speaker 2: want to know why is it. Newton tells you one story.

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Speaker 2: He says there's a force between these objects pulling on them.

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Speaker 2: Einstein tells you a different story. He says there's no

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Speaker 2: force there, there's no acceleration. That's the inertial motion of

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Speaker 2: the Earth through curved space time. Both stories are trying

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Speaker 2: to explain what we see, but they are describing very

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Speaker 2: different realities.

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Speaker 1: I guess what I mean is like, let's say you

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Speaker 1: take gravity out of the equation. Like, you're just talking

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Speaker 1: about two electrons in space repelling each other from their

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Speaker 1: electrical charge. Do you still need general relativity to describe

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Speaker 1: that motion. No.

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Speaker 2: In fact, we don't know how to do general relativity

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Speaker 2: on electrons. That's one of the problems.

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Speaker 1: Oh well, sounds like I just skipped ahead exactly.

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Speaker 2: So no, you do not need general relativity to describe

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Speaker 2: all the quantum interactions that exist, like in flat space,

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Speaker 2: two electrons out there, assume they're not perturbing space because

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Speaker 2: their masses are so small. Then no, we can do

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Speaker 2: quantum mechanics and explain all those electron interactions without general

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Speaker 2: relativity at all. Generalativity tells us about space and time

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Speaker 2: and gravity, and that's it. I mean, that's a lot

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Speaker 2: of stuff, but that's it all right.

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Speaker 1: So then what do you mean by how that this

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Speaker 1: theory might be wrong? Like, what would it mean for

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Speaker 1: iSight to be wrong?

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Speaker 2: Well, one way for theory to be wrong is for

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Speaker 2: it to make an incorrect prediction. Right If I say, look,

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Speaker 2: I'm fifty years old, and from zero to fifty I've

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Speaker 2: grown about a meter and a half. So therefore, in

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Speaker 2: my fifty years, I'm also going to grow a meter

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Speaker 2: and a half. That's a prediction. It's dumb, obviously, and

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Speaker 2: it's going to be disproven if I live another fifty

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Speaker 2: years and measure my height. So that's a theory that

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Speaker 2: can be proven wrong. Right, So if Einstein's theory makes

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Speaker 2: a prediction and that isn't born out by reality, we

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Speaker 2: do experiments that show that his predictions are wrong, that's

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Speaker 2: a scenario where we would say Einstein was wrong. How Else,

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Speaker 2: there's a sort of philosophical sense in which Einstein could

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Speaker 2: be wrong, which is all these theories of physics are

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Speaker 2: telling us the story. They're an explanation, and all of

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Speaker 2: our explanations in the end, are scientific stories about what's happening,

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Speaker 2: like why is the Earth moving this way? It's moving

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Speaker 2: this way because of the curvature of space time. But

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Speaker 2: those stories involve things we can't see, like we can't

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Speaker 2: directly observe the curvature of space time, we can't directly

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Speaker 2: see electric fields. These stories always involve invisible things that

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Speaker 2: we can't detect directly, And so then we wonder like, well,

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Speaker 2: what if those stories are wrong, do they actually describe

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Speaker 2: reality what's really happening, or are they just sort of

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Speaker 2: like the stories we're telling, even if they predict all

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Speaker 2: the experiments correctly, could they still be sort of philosophically wrong?

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Speaker 1: Is it sort of like, you know, how we thought

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Speaker 1: Newton was right for a long time, and it worked

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Speaker 1: to describe the motion of baseballs and billard balls, and

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Speaker 1: you know, the orbits of the planets, but it's not

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Speaker 1: really right at the end of the.

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Speaker 2: Day, exactly. We don't think that Newton's story is correct.

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Speaker 2: Newton's explanation for billiard balls and planets is not what's

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Speaker 2: actually happening, right, and so Newton can't be right. And

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Speaker 2: so in that sense we wonder like, well, if it's

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Speaker 2: not really philosophically true, is it possible that sometime in

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Speaker 2: the future, maybe not today, maybe well beyond our current capabilities,

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Speaker 2: that Einstein's theory could be proven wrong in some deep

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Speaker 2: future experiment. If it's fundamentally not described in the nature

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Speaker 2: of the universe, it might be possible to find a

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Speaker 2: way to prove that.

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Speaker 1: Well, apparently there's a whole cottage industry of people trying

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Speaker 1: to prove Einstein wrong. There have been many experiments, a

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Speaker 1: lot of different theories trying to bring the man down

443
00:22:01,440 --> 00:22:03,879
Speaker 1: and so let's dig into that and how exactly general

444
00:22:03,920 --> 00:22:16,760
Speaker 1: relativity is wrong. But first let's take a quick break.

445
00:22:20,320 --> 00:22:24,200
Speaker 1: All right, we're talking about how general relativity might be wrong,

446
00:22:24,600 --> 00:22:25,639
Speaker 1: might be or is wrong.

447
00:22:26,440 --> 00:22:28,840
Speaker 2: I'm pretty sure it is wrong. I mean, we don't

448
00:22:28,880 --> 00:22:31,000
Speaker 2: know for sure. But if I had the place a bet,

449
00:22:31,119 --> 00:22:32,920
Speaker 2: I put my money on Einstein is wrong.

450
00:22:34,400 --> 00:22:36,320
Speaker 1: Are you taking bets? Is there a pool online that

451
00:22:36,359 --> 00:22:37,840
Speaker 1: I can sign up for?

452
00:22:39,119 --> 00:22:40,239
Speaker 2: Oh, you want to bet against me?

453
00:22:41,920 --> 00:22:48,679
Speaker 1: You're betting against Einstein. I don't know who has the

454
00:22:48,720 --> 00:22:49,920
Speaker 1: better hair. You're Einstein.

455
00:22:52,680 --> 00:22:56,760
Speaker 2: Einstein is many things I aspire to, especially this hair

456
00:22:56,880 --> 00:22:59,160
Speaker 2: was all there yet. I know I'm not there yet.

457
00:23:00,080 --> 00:23:00,639
Speaker 1: You could die it.

458
00:23:00,680 --> 00:23:04,880
Speaker 2: I guess who dyes their hair white?

459
00:23:06,160 --> 00:23:09,240
Speaker 1: I don't know. Yeah, you could be the first person.

460
00:23:09,440 --> 00:23:11,760
Speaker 2: Yeah, I think dan Quayle died his Temple's great to

461
00:23:11,960 --> 00:23:14,080
Speaker 2: get a little bit more gravitas. There you go, But

462
00:23:14,200 --> 00:23:15,359
Speaker 2: I prefer the youthful look.

463
00:23:15,640 --> 00:23:18,000
Speaker 1: I see, I see, I'm.

464
00:23:17,840 --> 00:23:20,160
Speaker 2: No longer mistaken for a grad student in my department.

465
00:23:20,440 --> 00:23:23,320
Speaker 1: You don't need great hair in a while. You don't

466
00:23:23,320 --> 00:23:25,680
Speaker 1: need gravitas to prove gravity is wrong.

467
00:23:25,920 --> 00:23:28,960
Speaker 2: No, apparently you don't even need gray hairs. You just

468
00:23:29,040 --> 00:23:30,680
Speaker 2: need a great idea.

469
00:23:32,000 --> 00:23:37,119
Speaker 1: That is a grave bar too to pass. Well, it

470
00:23:37,160 --> 00:23:38,879
Speaker 1: sounds like a lot of people are trying or have

471
00:23:38,960 --> 00:23:41,720
Speaker 1: been trying to prove einsign wrong, or at least they've

472
00:23:41,800 --> 00:23:44,320
Speaker 1: been trying to make sure his theory is right. I

473
00:23:44,320 --> 00:23:45,959
Speaker 1: guess maybe is that a better way to put it.

474
00:23:46,560 --> 00:23:49,760
Speaker 2: Yeah, we have been trying to verify Einstein's theory, or

475
00:23:49,760 --> 00:23:52,119
Speaker 2: at least to check it or to see if it's wrong.

476
00:23:52,680 --> 00:23:56,640
Speaker 2: Because Einstein's theory of gravity doesn't just replace Newton's gravity,

477
00:23:56,720 --> 00:24:00,840
Speaker 2: it changes it. It makes different predictions from newton theory, and

478
00:24:00,880 --> 00:24:03,200
Speaker 2: that allows us to test it, to look for those

479
00:24:03,320 --> 00:24:07,520
Speaker 2: very specific predictions, those consequences of gravity actually being a

480
00:24:07,560 --> 00:24:10,960
Speaker 2: curvature of space time and not a force between two masses.

481
00:24:11,640 --> 00:24:13,600
Speaker 2: So for the last one hundred years or so, we've

482
00:24:13,600 --> 00:24:14,840
Speaker 2: been doing those tests.

483
00:24:15,160 --> 00:24:18,560
Speaker 1: Yeah, doing those tests and also making observations about the universe,

484
00:24:18,640 --> 00:24:20,919
Speaker 1: right as a way to test the theory.

485
00:24:21,240 --> 00:24:24,240
Speaker 2: Yeah, exactly. One way to look for new stuff is

486
00:24:24,280 --> 00:24:26,880
Speaker 2: just like build a new telescope, look deep into the universe,

487
00:24:26,880 --> 00:24:30,640
Speaker 2: wait for surprises. Another very very valuable way to discover

488
00:24:30,720 --> 00:24:34,119
Speaker 2: new stuff is to make very high precision tests of

489
00:24:34,160 --> 00:24:36,560
Speaker 2: your theory. You know, if your theory makes a very

490
00:24:36,560 --> 00:24:39,160
Speaker 2: specific prediction about what's going to happen, then go out

491
00:24:39,200 --> 00:24:42,280
Speaker 2: and do an experiment that's really really precise and check it.

492
00:24:42,359 --> 00:24:45,760
Speaker 2: Because if there's a small discrepancy, that's a hint maybe

493
00:24:45,760 --> 00:24:47,960
Speaker 2: this is something new going on, there's something wrong with

494
00:24:48,080 --> 00:24:50,520
Speaker 2: your theory or some piece of it you haven't accounted for.

495
00:24:50,880 --> 00:24:53,080
Speaker 2: We do that all the time in particle physics, for example,

496
00:24:53,280 --> 00:24:56,679
Speaker 2: we measure the mass of something super duper precisely and

497
00:24:56,720 --> 00:24:59,439
Speaker 2: see if the theory predicts it. Measure the interaction of

498
00:24:59,440 --> 00:25:02,359
Speaker 2: some particle really really precisely, and see if the theory

499
00:25:02,359 --> 00:25:03,360
Speaker 2: predicts it correctly.

500
00:25:03,440 --> 00:25:04,960
Speaker 1: All right, well, what are some of the ways in

501
00:25:05,000 --> 00:25:07,000
Speaker 1: which we've tested Einstein theories.

502
00:25:07,400 --> 00:25:10,680
Speaker 2: Well, one of the early successes was understanding the orbit

503
00:25:10,760 --> 00:25:14,160
Speaker 2: of mercury. You know, the planets orbit the Sun, and

504
00:25:14,240 --> 00:25:17,040
Speaker 2: in Newtonian physics, this is because there's a force there,

505
00:25:17,640 --> 00:25:20,560
Speaker 2: and Newton and Kepler were able to even describe not

506
00:25:20,640 --> 00:25:23,000
Speaker 2: just the circular motion of the planet, but the elliptical

507
00:25:23,080 --> 00:25:25,919
Speaker 2: motion of the planets. Right, the planets don't orbit in

508
00:25:26,000 --> 00:25:29,199
Speaker 2: perfect circles. They orbit in ellipses. But that's okay. In

509
00:25:29,240 --> 00:25:33,360
Speaker 2: Newtonian mechanics, you can have an elliptical orbit that's stable. Right,

510
00:25:33,400 --> 00:25:35,720
Speaker 2: the Sun pulls on things and then it goes faster when

511
00:25:35,720 --> 00:25:38,280
Speaker 2: it's closer and slower when it's further away. The math

512
00:25:38,320 --> 00:25:42,800
Speaker 2: all works out, But an ellipse has a direction to it. Right,

513
00:25:42,800 --> 00:25:44,720
Speaker 2: there's a bit of the ellipse that's longer and a

514
00:25:44,760 --> 00:25:47,760
Speaker 2: bit of the ellipse that's shorter, and procession means that

515
00:25:47,760 --> 00:25:50,560
Speaker 2: that ellipse is turning, like the direction that the ellipse

516
00:25:50,640 --> 00:25:53,560
Speaker 2: is longer and the pointy bits of the football is turning.

517
00:25:53,640 --> 00:25:56,000
Speaker 2: So that's what we call that the procession of the ellipse,

518
00:25:56,800 --> 00:26:00,199
Speaker 2: and Newton can also predict that procession. But what we

519
00:26:00,240 --> 00:26:03,400
Speaker 2: discovered is that the procession of the orbit of Mercury

520
00:26:03,600 --> 00:26:07,080
Speaker 2: was a little bit different from what Newton predicted, and

521
00:26:07,119 --> 00:26:10,720
Speaker 2: Einstein's theory predicted it correctly because it's a different story

522
00:26:10,920 --> 00:26:12,200
Speaker 2: about how gravity works.

523
00:26:13,200 --> 00:26:15,960
Speaker 1: But wait, why mercury, Like, what's different about mercury.

524
00:26:16,600 --> 00:26:19,040
Speaker 2: Well, Mercury is closest to the Sun. And one of

525
00:26:19,080 --> 00:26:23,639
Speaker 2: the crucial differences between Newtonian and Einsteinian gravity is what

526
00:26:23,760 --> 00:26:27,280
Speaker 2: happens when something is spinning. Like Newton says, if an

527
00:26:27,280 --> 00:26:29,560
Speaker 2: object has mass, then you're going to feel it's gravity,

528
00:26:29,640 --> 00:26:31,879
Speaker 2: and it doesn't matter if it's spinning. Take a sphere

529
00:26:31,880 --> 00:26:34,040
Speaker 2: of mass, if it's spinning or not. Newton says it

530
00:26:34,080 --> 00:26:36,879
Speaker 2: has the same gravity. It doesn't matter if it's spinning,

531
00:26:36,880 --> 00:26:39,640
Speaker 2: if it's a perfect sphere, because you always have masses

532
00:26:39,720 --> 00:26:42,760
Speaker 2: in the same place. But Einstein says it does matter

533
00:26:43,240 --> 00:26:46,280
Speaker 2: because Einstein's theory responds not just to the presence of

534
00:26:46,359 --> 00:26:49,880
Speaker 2: mass but energy, and something that's spinning has a different

535
00:26:50,080 --> 00:26:53,480
Speaker 2: energy than something that isn't spinning, and it actually twists

536
00:26:53,640 --> 00:26:56,440
Speaker 2: space time a little bit in a way that twists

537
00:26:56,480 --> 00:26:59,760
Speaker 2: things nearby, gives them little twists. So the Sun is

538
00:26:59,760 --> 00:27:03,640
Speaker 2: giving a little torque to Mercury's procession, according to Einstein

539
00:27:03,760 --> 00:27:06,480
Speaker 2: and not to Newton, and that little torque was enough

540
00:27:06,480 --> 00:27:09,080
Speaker 2: to explain the deviation in the orbit of Mercury.

541
00:27:09,320 --> 00:27:11,720
Speaker 1: WHOA, but you wouldn't feel this here on Earth.

542
00:27:12,000 --> 00:27:14,119
Speaker 2: It's a much smaller effect as you get further and

543
00:27:14,160 --> 00:27:17,520
Speaker 2: further away. But we've actually measured this ourselves. We've put

544
00:27:17,800 --> 00:27:21,680
Speaker 2: super precise satellites in orbit around the Earth to detect

545
00:27:21,760 --> 00:27:25,080
Speaker 2: the effect of the Earth spinning on stuff in orbit

546
00:27:25,119 --> 00:27:28,040
Speaker 2: around the Earth. We had an episode about gravity Probe

547
00:27:28,080 --> 00:27:32,200
Speaker 2: B which involves these incredible gyroscopes, which are the smoothest

548
00:27:32,280 --> 00:27:36,360
Speaker 2: objects known to man, These like incredible balls of quartz

549
00:27:36,440 --> 00:27:39,560
Speaker 2: mined in Brazil and polished by Grammas in Germany until

550
00:27:39,600 --> 00:27:43,439
Speaker 2: they're like incredibly spherical so that they're super precise, and

551
00:27:43,480 --> 00:27:46,320
Speaker 2: they have detected the same thing around the orbit of

552
00:27:46,320 --> 00:27:46,760
Speaker 2: the Earth.

553
00:27:47,359 --> 00:27:50,240
Speaker 1: WHOA, that's another way in which we've proven that Einstein

554
00:27:50,359 --> 00:27:50,640
Speaker 1: was right.

555
00:27:51,080 --> 00:27:53,800
Speaker 2: Yeah, exactly. All of these experiments and some of these

556
00:27:53,920 --> 00:27:57,080
Speaker 2: like they take decades to develop to make so precise,

557
00:27:57,359 --> 00:28:00,800
Speaker 2: and they always come out bang on ein Stein's prediction.

558
00:28:01,280 --> 00:28:02,440
Speaker 2: It's kind of infuriating.

559
00:28:03,000 --> 00:28:05,520
Speaker 1: What do you mean infuriating, Well, we.

560
00:28:05,480 --> 00:28:08,800
Speaker 2: Think Einstein is wrong, and so it's frustrating to not

561
00:28:08,920 --> 00:28:11,119
Speaker 2: be able to prove it right. As soon as we

562
00:28:11,240 --> 00:28:14,600
Speaker 2: find an example where Einstein is wrong, that's a thread

563
00:28:14,640 --> 00:28:16,560
Speaker 2: we can pull on. We can say, okay, here we go,

564
00:28:16,600 --> 00:28:19,359
Speaker 2: here's the lead. The thing is, we think Einstein was

565
00:28:19,400 --> 00:28:21,919
Speaker 2: probably wrong, but we don't know how to improve his theory,

566
00:28:22,320 --> 00:28:24,840
Speaker 2: and until we find a place to where it fails,

567
00:28:25,200 --> 00:28:26,800
Speaker 2: it's difficult to know how to proceed.

568
00:28:28,920 --> 00:28:31,480
Speaker 1: So in the gravity of things and how spinning things

569
00:28:31,600 --> 00:28:34,359
Speaker 1: affect gravity, because Einstein predicted that it would, right.

570
00:28:35,160 --> 00:28:36,480
Speaker 2: Einstein predicted that it would.

571
00:28:36,560 --> 00:28:39,200
Speaker 1: So something that spinning has more gravity to it, Like

572
00:28:39,240 --> 00:28:41,640
Speaker 1: if the Earth was spinning faster, we'd all be heavier.

573
00:28:42,160 --> 00:28:45,920
Speaker 2: It's not just more gravity, right. Newton's equation is one equation,

574
00:28:45,960 --> 00:28:49,240
Speaker 2: it's a single force equation. It tells you the magnitude

575
00:28:49,280 --> 00:28:51,719
Speaker 2: of the force and the direction of it. But Einstein's

576
00:28:51,760 --> 00:28:55,240
Speaker 2: equation is a tenser equation. It's like a big matrix

577
00:28:55,360 --> 00:28:58,280
Speaker 2: of equations and tells you gravity is much more complicated

578
00:28:58,320 --> 00:29:00,320
Speaker 2: than just like a force and a direction, and it

579
00:29:00,320 --> 00:29:03,680
Speaker 2: can also apply a torque. There's all sorts of complicated things.

580
00:29:03,960 --> 00:29:06,320
Speaker 2: So it's not just about more gravity, it's about what

581
00:29:06,360 --> 00:29:07,480
Speaker 2: that gravity is doing.

582
00:29:08,320 --> 00:29:10,520
Speaker 1: But is that true? If the Earth was spinning faster,

583
00:29:10,600 --> 00:29:11,360
Speaker 1: I would be heavier.

584
00:29:11,520 --> 00:29:13,680
Speaker 2: If the Earth was spinning faster, the Earth would be

585
00:29:13,680 --> 00:29:17,240
Speaker 2: twisting you a little bit. It wouldn't necessarily make you heavier,

586
00:29:17,400 --> 00:29:18,320
Speaker 2: it'd be spinning you.

587
00:29:19,080 --> 00:29:19,320
Speaker 3: Oh.

588
00:29:19,360 --> 00:29:21,840
Speaker 1: But then you say, like it affects the gravity, like

589
00:29:21,880 --> 00:29:24,080
Speaker 1: it maybe increases the gravity of the Earth.

590
00:29:24,320 --> 00:29:27,320
Speaker 2: Yeah. I think that's true. Because the overall energy is higher,

591
00:29:27,840 --> 00:29:31,000
Speaker 2: then you would get more curvature. But also that curvature

592
00:29:31,080 --> 00:29:33,840
Speaker 2: is more complicated, so it induces a little torque on

593
00:29:33,960 --> 00:29:34,880
Speaker 2: objects nearby.

594
00:29:35,640 --> 00:29:38,280
Speaker 1: There's sort of like a little eddy current in gravity.

595
00:29:38,320 --> 00:29:40,640
Speaker 2: Right, This is called frame dragging. Check out our episodes

596
00:29:40,680 --> 00:29:41,880
Speaker 2: about that if you want more details.

597
00:29:41,960 --> 00:29:44,280
Speaker 1: Yeah, what are some of the other ways in which

598
00:29:44,480 --> 00:29:46,000
Speaker 1: people have tested Einstein?

599
00:29:46,360 --> 00:29:48,280
Speaker 2: So a lot of these tests we just described are

600
00:29:48,320 --> 00:29:51,840
Speaker 2: sort of weak field gravity gravity in places where space

601
00:29:51,920 --> 00:29:54,640
Speaker 2: is curved, but not like dramatically curved. One of the

602
00:29:54,680 --> 00:29:58,400
Speaker 2: really dramatic predictions of Einstein's theory is that space can curve,

603
00:29:58,560 --> 00:30:02,880
Speaker 2: incredibly powerfully curve and create things like black holes. And

604
00:30:02,920 --> 00:30:06,000
Speaker 2: for a long time people thought, well, that's obviously wrong, right,

605
00:30:06,000 --> 00:30:08,840
Speaker 2: that's ridiculous. But then we went out and we saw

606
00:30:08,920 --> 00:30:11,920
Speaker 2: black holes in the universe. And so the fact that

607
00:30:11,960 --> 00:30:15,240
Speaker 2: black holes exist is that there's an event horizon beyond

608
00:30:15,320 --> 00:30:19,440
Speaker 2: which information cannot escape is a direct prediction of general relativity,

609
00:30:19,640 --> 00:30:22,640
Speaker 2: not of Newtonian physics, and something we've seen in the

610
00:30:22,760 --> 00:30:23,720
Speaker 2: universe but we.

611
00:30:23,720 --> 00:30:26,640
Speaker 1: Think we've seen. Right, then we talk about before how

612
00:30:26,960 --> 00:30:30,280
Speaker 1: nobody has actually technically seen a black hole or confirmed

613
00:30:30,520 --> 00:30:31,200
Speaker 1: its existence.

614
00:30:31,480 --> 00:30:34,080
Speaker 2: Yeah, that's an important caveat right, We've seen things that

615
00:30:34,080 --> 00:30:37,360
Speaker 2: are very consistent with black holes. There are some alternative

616
00:30:37,360 --> 00:30:41,680
Speaker 2: theories dark stars, boson stars, fuzzy string balls, et cetera,

617
00:30:41,720 --> 00:30:45,080
Speaker 2: et cetera. The most mainstream interpretation of those is that

618
00:30:45,120 --> 00:30:48,560
Speaker 2: they are black holes. They're totally consistent with black holes.

619
00:30:48,800 --> 00:30:51,640
Speaker 2: But you're right, we've never actually confirmed the existence of

620
00:30:51,680 --> 00:30:54,360
Speaker 2: an event horizon in the universe.

621
00:30:54,240 --> 00:30:56,160
Speaker 1: Right, or what's inside of it, right.

622
00:30:56,160 --> 00:30:57,560
Speaker 2: Yeah, or what's inside of it.

623
00:30:57,640 --> 00:30:59,840
Speaker 1: But we have to sort of used black holes in

624
00:31:00,400 --> 00:31:03,520
Speaker 1: to prove that the gravitational waves exist, which is part

625
00:31:03,560 --> 00:31:05,640
Speaker 1: of Eystein's theory, right exactly.

626
00:31:06,000 --> 00:31:10,239
Speaker 2: Another important distinction between Einsteinian and Newtonian gravity is that

627
00:31:10,280 --> 00:31:14,240
Speaker 2: gravity takes time. That information is not instantly propagated in

628
00:31:14,240 --> 00:31:17,080
Speaker 2: the universe. Newton says, if you delete the Sun from

629
00:31:17,120 --> 00:31:20,800
Speaker 2: the universe, it's gravity disappears instantly. But Einstein's spent a

630
00:31:20,800 --> 00:31:23,200
Speaker 2: lot of time thinking about how information is propagated. He

631
00:31:23,240 --> 00:31:26,000
Speaker 2: developed the theory of special relativity, and so in general

632
00:31:26,040 --> 00:31:28,520
Speaker 2: relativity he accounts for this. He says that it takes

633
00:31:28,560 --> 00:31:32,320
Speaker 2: time for gravitational information to propagate, and that propagates via

634
00:31:32,400 --> 00:31:35,640
Speaker 2: gravitational waves. So you take a black hole, for example,

635
00:31:35,720 --> 00:31:37,800
Speaker 2: or even a sun or a big rock and you

636
00:31:37,840 --> 00:31:41,600
Speaker 2: wiggle it. Then the curvature it's causing wiggles as you

637
00:31:41,680 --> 00:31:44,360
Speaker 2: wiggle the rock. You can detect this if you have

638
00:31:44,440 --> 00:31:48,080
Speaker 2: really big sources of gravitational waves, like black holes eating

639
00:31:48,120 --> 00:31:50,480
Speaker 2: each other as they spiral around each other, they make

640
00:31:50,520 --> 00:31:54,280
Speaker 2: these gravitational waves and we've detected them. This is another

641
00:31:54,440 --> 00:31:58,240
Speaker 2: crazy prediction that I personally thought would never be borne out.

642
00:31:58,400 --> 00:32:02,240
Speaker 2: But again due to like amazing seeing technical and experimental bravado,

643
00:32:02,560 --> 00:32:04,680
Speaker 2: they figured out how to see these things and we've

644
00:32:04,720 --> 00:32:09,000
Speaker 2: confirmed them and the predictions are bang on Einstein's calculations.

645
00:32:09,360 --> 00:32:12,000
Speaker 1: Yeah, that's some amazing engineering going on there, right.

646
00:32:12,120 --> 00:32:13,120
Speaker 2: It really is impressive.

647
00:32:15,040 --> 00:32:17,520
Speaker 1: They probably deserve their retirement engineers.

648
00:32:17,960 --> 00:32:20,960
Speaker 2: Well, they definitely deserve the Nobel Prizes that they won

649
00:32:21,000 --> 00:32:22,760
Speaker 2: for it. I was thinking about where to go to

650
00:32:22,800 --> 00:32:25,280
Speaker 2: grad school in the late nineties and thinking about, you know,

651
00:32:25,320 --> 00:32:29,080
Speaker 2: particle physics at Berkeley or gravitational waves at Caltech, and

652
00:32:29,160 --> 00:32:32,440
Speaker 2: I definitely chose particle physics at Berkeley because I thought

653
00:32:32,440 --> 00:32:34,920
Speaker 2: they would never see those gravitational waves.

654
00:32:34,960 --> 00:32:37,920
Speaker 1: I thought it was crazy, and you could own part

655
00:32:37,960 --> 00:32:40,720
Speaker 1: of a Nobel Prize right now had you chosen another.

656
00:32:40,440 --> 00:32:43,280
Speaker 2: Path, absolutely, you know, have the path not taken.

657
00:32:43,640 --> 00:32:46,000
Speaker 1: But instead now they are retired engineers who have part

658
00:32:46,040 --> 00:32:47,320
Speaker 1: of a Nobel Prize, but you don't.

659
00:32:47,400 --> 00:32:50,000
Speaker 2: Yeah exactly. But you know there's another version of that

660
00:32:50,080 --> 00:32:52,720
Speaker 2: story where I did join the project and I messed

661
00:32:52,720 --> 00:32:55,080
Speaker 2: it all up and they never discovered gravitation. Oh yeah,

662
00:32:55,160 --> 00:32:57,920
Speaker 2: So maybe I was doing everybody a favor by staying

663
00:32:57,920 --> 00:32:58,280
Speaker 2: out of it.

664
00:32:58,440 --> 00:33:00,600
Speaker 1: That's right, you get account for all plus abilit.

665
00:33:00,520 --> 00:33:02,040
Speaker 2: I'm what I'm saying is I get to share that

666
00:33:02,080 --> 00:33:04,160
Speaker 2: Nobel Prize by not messing it up.

667
00:33:04,360 --> 00:33:12,400
Speaker 1: Really, Daniel done, so does everybody else who's ever existed.

668
00:33:12,520 --> 00:33:14,959
Speaker 2: I mean we're always saying everybody is a scientist, right,

669
00:33:15,000 --> 00:33:17,000
Speaker 2: so shouldn't we all reap the benefits.

670
00:33:17,480 --> 00:33:19,360
Speaker 1: Well, I think we all get the benefits, but not

671
00:33:19,400 --> 00:33:24,400
Speaker 1: necessarily the credit or the not credit for not getting

672
00:33:24,400 --> 00:33:24,680
Speaker 1: the way.

673
00:33:24,840 --> 00:33:27,120
Speaker 2: I mean, there's so many discoveries out there that I

674
00:33:27,160 --> 00:33:28,840
Speaker 2: didn't mess up. I don't know why I'm not getting

675
00:33:28,840 --> 00:33:29,400
Speaker 2: credit for that.

676
00:33:29,520 --> 00:33:31,960
Speaker 1: I know there should be just a prize just for you.

677
00:33:32,280 --> 00:33:33,120
Speaker 1: They should thank me.

678
00:33:33,360 --> 00:33:36,080
Speaker 2: Every year, Thank you Daniel for not being involved and

679
00:33:36,160 --> 00:33:37,120
Speaker 2: not messing this one up.

680
00:33:38,000 --> 00:33:41,840
Speaker 1: That's right. Daniel Whitson ignored us a price.

681
00:33:43,360 --> 00:33:47,280
Speaker 2: Yeah exactly, But anyway, it's an incredible accomplishment. Nobel Prize

682
00:33:47,320 --> 00:33:48,440
Speaker 2: is very well deserved.

683
00:33:48,560 --> 00:33:50,760
Speaker 1: Yeah, and so that's one way in which we confirm

684
00:33:51,440 --> 00:33:54,320
Speaker 1: general relativity, right, because you can only get gravitational waves

685
00:33:54,480 --> 00:33:59,000
Speaker 1: with general relativity, or is there another explanation for them?

686
00:33:59,200 --> 00:34:02,560
Speaker 2: There's no other explanation for gravitational waves. I mean other

687
00:34:02,760 --> 00:34:06,200
Speaker 2: variations of general relativity that we might talk about, you know,

688
00:34:06,240 --> 00:34:08,799
Speaker 2: ways to build on general relativity. But you can't get

689
00:34:08,840 --> 00:34:13,239
Speaker 2: gravitational waves in Newtonian gravity. You need the curvature of

690
00:34:13,239 --> 00:34:18,560
Speaker 2: space time and general relativity to have that prediction, all.

691
00:34:18,520 --> 00:34:22,400
Speaker 1: Right, So that's another box that general relativity checked. What

692
00:34:22,640 --> 00:34:25,399
Speaker 1: are some of the other boxes that it has passed well?

693
00:34:25,440 --> 00:34:29,680
Speaker 2: Affects like gravitational lensing because space is curved when light

694
00:34:29,760 --> 00:34:33,280
Speaker 2: passes through it, it follows that curvature, and so light moving

695
00:34:33,320 --> 00:34:36,799
Speaker 2: around really massive objects doesn't move and what looks like

696
00:34:36,840 --> 00:34:39,480
Speaker 2: a straight line to us if we're far away and

697
00:34:39,520 --> 00:34:41,200
Speaker 2: we can see this in the sky, we can see

698
00:34:41,320 --> 00:34:45,279
Speaker 2: light bending around invisible dark matter and creating distortions in

699
00:34:45,400 --> 00:34:49,319
Speaker 2: background galaxies. This effect occurs all over the place in

700
00:34:49,360 --> 00:34:52,640
Speaker 2: the sky and it's been confirmed many, many times. So

701
00:34:53,040 --> 00:34:55,880
Speaker 2: we definitely know that light is curved as it passes

702
00:34:55,920 --> 00:34:56,880
Speaker 2: through bend space.

703
00:34:58,080 --> 00:35:00,360
Speaker 1: This is an interesting one because I feel like anyone

704
00:35:00,440 --> 00:35:03,319
Speaker 1: can confirm and look out there into the universe to

705
00:35:03,320 --> 00:35:05,440
Speaker 1: do this right, Like you don't need to build a

706
00:35:05,480 --> 00:35:08,759
Speaker 1: super special satellite or a super giant detector, Like you

707
00:35:08,760 --> 00:35:11,600
Speaker 1: could just look out into this into space and confirm

708
00:35:11,840 --> 00:35:14,600
Speaker 1: that space is being bent out there.

709
00:35:14,920 --> 00:35:16,560
Speaker 2: Yeah, I'm not sure you could do it with like

710
00:35:16,600 --> 00:35:19,759
Speaker 2: a backyard telescope. You need sort of precise measurements, but.

711
00:35:19,840 --> 00:35:20,840
Speaker 1: You haven't seen my backyard.

712
00:35:20,920 --> 00:35:26,759
Speaker 2: Then retired engineers have a lot of disposable income and

713
00:35:26,840 --> 00:35:30,799
Speaker 2: maybe they have really fancy telescopes in their backyard. But yeah,

714
00:35:30,800 --> 00:35:31,120
Speaker 2: you can.

715
00:35:31,000 --> 00:35:32,440
Speaker 1: See or like you know, you could go to a

716
00:35:32,480 --> 00:35:35,920
Speaker 1: local observatory maybe yeah, or a big one and like

717
00:35:35,960 --> 00:35:38,319
Speaker 1: you can step right up to the lens and take a.

718
00:35:38,280 --> 00:35:42,239
Speaker 2: Look right exactly. Sometimes you can see galaxies duplicated, like

719
00:35:42,280 --> 00:35:45,320
Speaker 2: the same galaxy in two places in the sky because

720
00:35:45,320 --> 00:35:48,520
Speaker 2: photons from that galaxy bend around some object and appear

721
00:35:48,560 --> 00:35:51,319
Speaker 2: to be coming from two different directions. You can see

722
00:35:51,320 --> 00:35:55,239
Speaker 2: what's called an Einstein cross, effectively like an optical distortion

723
00:35:55,920 --> 00:35:58,480
Speaker 2: of our vision because of this curvature. So yeah, you

724
00:35:58,520 --> 00:36:00,840
Speaker 2: can just look through a telescope and you can see

725
00:36:01,080 --> 00:36:02,160
Speaker 2: gravitational lensing.

726
00:36:02,520 --> 00:36:05,280
Speaker 1: Now, and now this is significant because it basically shows

727
00:36:05,320 --> 00:36:09,400
Speaker 1: that light is affected by gravity, which is significant because

728
00:36:09,800 --> 00:36:13,680
Speaker 1: light doesn't have any mass, right, yeah, so it wouldn't, nominally,

729
00:36:14,520 --> 00:36:19,560
Speaker 1: according to Newton, feel a force of gravity, and yet

730
00:36:19,640 --> 00:36:23,680
Speaker 1: it's being pulled and pushed by the mass of other objects.

731
00:36:23,400 --> 00:36:28,040
Speaker 2: Exactly because it's moving through that curved space, and masses

732
00:36:28,120 --> 00:36:31,280
Speaker 2: bend space and everything moves through that curved space.

733
00:36:32,040 --> 00:36:34,879
Speaker 1: Although doesn't it also maybe depend on what you mean

734
00:36:34,920 --> 00:36:37,800
Speaker 1: by mass, Like if you mean any kind of energy

735
00:36:37,880 --> 00:36:40,520
Speaker 1: is massd then could that also explain the curvature of

736
00:36:40,600 --> 00:36:44,000
Speaker 1: light without general relativity? You know, like let's say a

737
00:36:44,000 --> 00:36:47,600
Speaker 1: photon doesn't have any mass in the traditional sense, but

738
00:36:47,680 --> 00:36:50,400
Speaker 1: it has energy to it it does. Yeah, yeah, And

739
00:36:50,440 --> 00:36:52,920
Speaker 1: now let's say that I call mass something different like

740
00:36:53,040 --> 00:36:55,960
Speaker 1: mass now not just the mass we used to call mass,

741
00:36:55,960 --> 00:36:58,480
Speaker 1: but also energy like the energy of photon might have,

742
00:36:59,280 --> 00:37:03,400
Speaker 1: and then it was a force from gravity because of

743
00:37:03,400 --> 00:37:07,239
Speaker 1: this energy mass. Couldn't I also maybe explain the curvature

744
00:37:07,400 --> 00:37:09,800
Speaker 1: of light with Newtonian physics?

745
00:37:09,920 --> 00:37:10,000
Speaker 3: Oh?

746
00:37:10,080 --> 00:37:12,399
Speaker 2: I see, could you make some sort of like Newtonian

747
00:37:12,560 --> 00:37:16,040
Speaker 2: version of gravity where you generalize it from just mass

748
00:37:16,040 --> 00:37:18,799
Speaker 2: to energy and say, you know, the Whoregey theory of

749
00:37:18,840 --> 00:37:21,600
Speaker 2: gravity is that there's a force between objects with energy,

750
00:37:21,719 --> 00:37:22,840
Speaker 2: not just with mass.

751
00:37:23,000 --> 00:37:28,280
Speaker 1: Yes, the Whoregey theory of light and gravity future novel

752
00:37:28,360 --> 00:37:30,200
Speaker 1: prize winning theory.

753
00:37:30,840 --> 00:37:33,120
Speaker 2: Yeah, yeah, absolutely, you can do that. And people have

754
00:37:33,120 --> 00:37:35,840
Speaker 2: actually tried to do this to build like a bridge

755
00:37:35,880 --> 00:37:39,640
Speaker 2: between Newtonian and Einsteinian theories. One thing we do when

756
00:37:39,640 --> 00:37:41,040
Speaker 2: we come up with a brand new theory is we

757
00:37:41,080 --> 00:37:43,640
Speaker 2: try to understand, like, is the old theory a special

758
00:37:43,680 --> 00:37:45,560
Speaker 2: case of this new theory. How do they fit together?

759
00:37:45,680 --> 00:37:48,200
Speaker 2: Is one at generalization of the other one? And so

760
00:37:48,239 --> 00:37:50,440
Speaker 2: people have actually gone back and tried to like patch

761
00:37:50,520 --> 00:37:53,440
Speaker 2: these things together and say, could you go from Newtonian

762
00:37:53,480 --> 00:37:56,960
Speaker 2: physics to Einsteinian physics using that direction to avoid the

763
00:37:56,960 --> 00:38:00,719
Speaker 2: interpretation of curvature. And there are some that you can

764
00:38:00,800 --> 00:38:04,480
Speaker 2: get right. For example, you can describe how light bends

765
00:38:04,760 --> 00:38:08,680
Speaker 2: using this apparent force between energy rather than a force

766
00:38:08,719 --> 00:38:11,440
Speaker 2: between mass. But you can't get all the details right

767
00:38:11,760 --> 00:38:14,400
Speaker 2: of the curvature of space time. There's more information in

768
00:38:14,440 --> 00:38:17,080
Speaker 2: there in the metric and the curvature of space time

769
00:38:17,280 --> 00:38:19,279
Speaker 2: that can just be described by the force. It's sort

770
00:38:19,320 --> 00:38:20,560
Speaker 2: of like a richer theory.

771
00:38:22,200 --> 00:38:23,640
Speaker 1: I see, so I think. I guess what I was

772
00:38:23,680 --> 00:38:26,280
Speaker 1: trying to get to is that, you know, gravitational lensing

773
00:38:26,640 --> 00:38:29,040
Speaker 1: is a test of gravity, but it's not like a

774
00:38:29,080 --> 00:38:34,400
Speaker 1: slam dunk case of gravity, right of general relativity exactly.

775
00:38:34,800 --> 00:38:37,440
Speaker 2: You can add bells and whistles to Newton's theory to

776
00:38:37,600 --> 00:38:39,200
Speaker 2: make gravitational lensing happen.

777
00:38:39,360 --> 00:38:42,400
Speaker 1: Yeah. Yeah, it's called the bells and whistles theory of

778
00:38:42,440 --> 00:38:47,359
Speaker 1: the universe, the B and W. All right, well, let's

779
00:38:47,400 --> 00:38:50,920
Speaker 1: get into how else we know that general relativity is wrong,

780
00:38:51,000 --> 00:38:53,640
Speaker 1: and let's talk about how it's wrong and where we

781
00:38:53,640 --> 00:38:56,279
Speaker 1: think it might finally break. So let's stick into that.

782
00:38:56,360 --> 00:39:11,440
Speaker 1: But first let's take another quick break. All right, we're

783
00:39:11,440 --> 00:39:14,920
Speaker 1: talking about general relativity, the big theory that Einstein came

784
00:39:14,960 --> 00:39:17,319
Speaker 1: up with. The talks about gravity and how space can

785
00:39:17,440 --> 00:39:21,200
Speaker 1: bend and how space time gets bent by things like

786
00:39:21,280 --> 00:39:24,440
Speaker 1: mass and energy, and how it might be wrong. Although

787
00:39:24,480 --> 00:39:26,880
Speaker 1: it seems pretty right from all the experiments we've done.

788
00:39:27,560 --> 00:39:31,120
Speaker 2: So far, it's been endlessly vinegated, which is frustrating because

789
00:39:31,200 --> 00:39:32,360
Speaker 2: I'm pretty sure it's wrong.

790
00:39:32,840 --> 00:39:33,920
Speaker 1: What are you so short?

791
00:39:35,560 --> 00:39:38,840
Speaker 2: Even though every test we've done has confirmed Einstein's prediction,

792
00:39:39,280 --> 00:39:42,440
Speaker 2: we think that there are scenarios where it must break down.

793
00:39:42,880 --> 00:39:45,399
Speaker 2: Not tests we can do today, but test we can

794
00:39:45,440 --> 00:39:48,600
Speaker 2: imagine with thought experiments places in the universe where we

795
00:39:48,600 --> 00:39:50,640
Speaker 2: think Einstein's theory can't be right.

796
00:39:51,160 --> 00:39:54,440
Speaker 1: Interesting. So you're saying, like, it's as right as far

797
00:39:54,480 --> 00:39:57,960
Speaker 1: as we know and the phenomena we've seen, but there

798
00:39:58,000 --> 00:40:00,640
Speaker 1: might be situations where it breaks down.

799
00:40:00,880 --> 00:40:02,840
Speaker 2: We think that there are situations where it has to

800
00:40:02,880 --> 00:40:05,120
Speaker 2: be wrong, even though we haven't yet been able to

801
00:40:05,160 --> 00:40:09,160
Speaker 2: engineer any of those situations in the lab to prove it.

802
00:40:09,200 --> 00:40:11,920
Speaker 2: But there are sort of thought experiments or future experiments

803
00:40:11,920 --> 00:40:15,120
Speaker 2: we can predict or places in the universe where we

804
00:40:15,160 --> 00:40:16,479
Speaker 2: think it's got to be wrong.

805
00:40:16,880 --> 00:40:19,680
Speaker 1: Uh. Interesting, All right, well let's step through these scenarios.

806
00:40:19,719 --> 00:40:20,600
Speaker 1: What are these places?

807
00:40:20,800 --> 00:40:23,120
Speaker 2: Yeah, well, one was the scenario you brought up earlier,

808
00:40:23,200 --> 00:40:26,960
Speaker 2: like what happens between two electrons? What is the gravitational

809
00:40:27,040 --> 00:40:30,520
Speaker 2: force between two electrons? Because electrons are not just like

810
00:40:30,680 --> 00:40:34,359
Speaker 2: tiny little versions of planets. They're not just like small

811
00:40:34,440 --> 00:40:37,279
Speaker 2: planets with tiny little masses in them where you can

812
00:40:37,320 --> 00:40:40,240
Speaker 2: apply Newtonian physics or think about the curvature of space.

813
00:40:40,600 --> 00:40:44,719
Speaker 2: They're fundamentally different from planets. They're probabilistic. We know that

814
00:40:44,760 --> 00:40:49,240
Speaker 2: electrons are quantum objects. They don't have a definitive location.

815
00:40:49,320 --> 00:40:51,959
Speaker 2: They have a probability for being here and a probability

816
00:40:51,960 --> 00:40:55,480
Speaker 2: for being there. They can interfere with each other, and

817
00:40:55,600 --> 00:40:58,640
Speaker 2: Einstein's theory doesn't account for that. It doesn't allow for that.

818
00:40:58,680 --> 00:41:03,160
Speaker 2: It says, Look, things have locations, and those locations determine

819
00:41:03,160 --> 00:41:05,879
Speaker 2: how space curves. So we don't know what to do

820
00:41:05,920 --> 00:41:09,960
Speaker 2: when things don't have locations, The space curve randomly the

821
00:41:10,000 --> 00:41:12,799
Speaker 2: space curve probabilistically. What's going on?

822
00:41:13,239 --> 00:41:16,120
Speaker 1: But other theories can can deal with that, like could

823
00:41:16,160 --> 00:41:18,200
Speaker 1: Neaton handle a quantum object? No.

824
00:41:18,360 --> 00:41:21,839
Speaker 2: Newton's theory also requires you to know where something is,

825
00:41:22,120 --> 00:41:24,160
Speaker 2: Like if you're going to feel the force of gravity

826
00:41:24,200 --> 00:41:25,879
Speaker 2: from an electron, you got to know how far away

827
00:41:25,920 --> 00:41:28,440
Speaker 2: it is and in what direction. If an electron like

828
00:41:28,480 --> 00:41:30,640
Speaker 2: could be to your left and could be to your right,

829
00:41:31,160 --> 00:41:33,720
Speaker 2: then what gravity are you feeling? Are you feeling gravity

830
00:41:33,719 --> 00:41:35,520
Speaker 2: to the left, are you feeling gravity to the right?

831
00:41:35,719 --> 00:41:38,000
Speaker 2: Are you feeling fifty to fifty gravity to the left

832
00:41:38,040 --> 00:41:40,879
Speaker 2: and right? So it cancels itself out, like Newton also

833
00:41:40,960 --> 00:41:42,840
Speaker 2: doesn't know what to do in that situation.

834
00:41:43,160 --> 00:41:45,960
Speaker 1: Wait, what so then how do you do anything with

835
00:41:46,040 --> 00:41:48,360
Speaker 1: quantum mechanics, like how do you how do you compute

836
00:41:48,360 --> 00:41:49,560
Speaker 1: the path of an electron?

837
00:41:49,719 --> 00:41:52,840
Speaker 2: Yeah, mostly we ignore gravity. Like when we compute the

838
00:41:52,840 --> 00:41:55,799
Speaker 2: path with an electron or electrons interacting, we assume that

839
00:41:55,800 --> 00:41:58,800
Speaker 2: there's no gravity. We do those all in flat space.

840
00:41:59,239 --> 00:42:01,279
Speaker 1: But then how do you how do you like, if

841
00:42:01,719 --> 00:42:04,400
Speaker 1: another electron pushes it or pulls it, how do you

842
00:42:04,480 --> 00:42:06,759
Speaker 1: make that calculation of where it's going to go?

843
00:42:07,440 --> 00:42:09,480
Speaker 2: Well, we just assume that there is no gravity, and

844
00:42:09,520 --> 00:42:12,080
Speaker 2: we do the quant mechanical version of things. Because all

845
00:42:12,120 --> 00:42:15,480
Speaker 2: the other forces, the pushing and the pulling of electromagnetism

846
00:42:16,040 --> 00:42:19,320
Speaker 2: that allows for this probabilistic stuff. We have a quantum

847
00:42:19,400 --> 00:42:22,279
Speaker 2: theory of electromagnetic forces, and a quantum theory of the

848
00:42:22,320 --> 00:42:24,840
Speaker 2: strong force and the weak force. All the forces in

849
00:42:24,880 --> 00:42:28,719
Speaker 2: the universe we can describe using quantum mechanics, and those

850
00:42:28,760 --> 00:42:33,239
Speaker 2: quantum descriptions can totally accommodate these sort of probabilities and interference.

851
00:42:34,120 --> 00:42:37,600
Speaker 1: And it just lets you compute like the arc or

852
00:42:37,760 --> 00:42:39,160
Speaker 1: trajectory of an electron.

853
00:42:39,400 --> 00:42:43,200
Speaker 2: It lets you compute the probability of various outcomes. Absolutely,

854
00:42:43,640 --> 00:42:47,040
Speaker 2: so quantum mechanics is totally cool with that. And when

855
00:42:47,080 --> 00:42:49,239
Speaker 2: we do that, we have to ignore gravity. You might ask, well,

856
00:42:49,320 --> 00:42:52,399
Speaker 2: how can you get the right answer if you're ignoring gravity. Well,

857
00:42:52,440 --> 00:42:55,560
Speaker 2: gravity is super duper weak. It's so much weaker than

858
00:42:55,600 --> 00:42:58,839
Speaker 2: any of these other forces, so it's basically negligible. Like

859
00:42:58,960 --> 00:43:01,680
Speaker 2: we couldn't actually even measure the mass of an electron

860
00:43:02,160 --> 00:43:04,719
Speaker 2: using gravity. We talked recently on the podcast about like

861
00:43:05,040 --> 00:43:08,719
Speaker 2: the smallest thing we've ever measured the gravity for. It

862
00:43:08,760 --> 00:43:11,160
Speaker 2: was like around a kilogram or a little bit smaller.

863
00:43:11,200 --> 00:43:14,680
Speaker 2: You know, zillions and zillions of atoms, So we can't

864
00:43:14,719 --> 00:43:17,560
Speaker 2: detect the gravity these particles. We just ignore it in

865
00:43:17,560 --> 00:43:20,279
Speaker 2: our calculations for particle physics because we also don't know

866
00:43:20,320 --> 00:43:21,680
Speaker 2: how to do those calculations.

867
00:43:22,040 --> 00:43:23,600
Speaker 1: But I wonder if you mean, like only at the

868
00:43:23,800 --> 00:43:27,560
Speaker 1: microscopic level, Like, for example, can I treat an electron

869
00:43:28,120 --> 00:43:31,280
Speaker 1: as a little point particle like a little tiny baseball

870
00:43:31,520 --> 00:43:34,320
Speaker 1: and throw it at the Earth. Wouldn't even like Newtonian

871
00:43:34,320 --> 00:43:37,839
Speaker 1: physics tell me at least the most likely path that

872
00:43:37,880 --> 00:43:38,839
Speaker 1: electron is going to take.

873
00:43:39,560 --> 00:43:42,640
Speaker 2: Yeah, absolutely, you can do those calculations, and we actually

874
00:43:42,640 --> 00:43:45,359
Speaker 2: do those calculations. When we think about like the atmosphere,

875
00:43:45,680 --> 00:43:48,440
Speaker 2: how much atmosphere are we losing. Well, it depends on

876
00:43:48,480 --> 00:43:51,840
Speaker 2: the velocity and the gravity of the atoms in the

877
00:43:51,920 --> 00:43:54,560
Speaker 2: upper atmosphere. We lose more hydrogen and helium than the

878
00:43:54,600 --> 00:43:57,880
Speaker 2: heavier elements because they have more gravity. The Earth is

879
00:43:57,920 --> 00:44:01,280
Speaker 2: pulling on them harder. But there we're doing a classical calculation.

880
00:44:01,280 --> 00:44:04,800
Speaker 2: We're ignoring the quantum nature of those objects. Whenever the

881
00:44:04,880 --> 00:44:08,839
Speaker 2: quantum nature is relevant, gravity becomes irrelevant. And that's one

882
00:44:08,840 --> 00:44:11,840
Speaker 2: of the frustrating things about testing Einstein's theory is that

883
00:44:11,880 --> 00:44:14,759
Speaker 2: it's mostly irrelevant in places where we think it's going

884
00:44:14,840 --> 00:44:19,879
Speaker 2: to fail. Like we think that Einstein's theory breaks down

885
00:44:19,920 --> 00:44:23,840
Speaker 2: for quantum particles, but it's also irrelevant for quantum particles

886
00:44:23,840 --> 00:44:26,000
Speaker 2: because quantum particles have almost no mass.

887
00:44:26,560 --> 00:44:28,759
Speaker 1: Well, I think what you're saying is that it does

888
00:44:28,800 --> 00:44:33,000
Speaker 1: work for quantum particles, just not at a certain level. Right, Like,

889
00:44:33,200 --> 00:44:37,239
Speaker 1: you can use general relativity and Newtonian physics on an

890
00:44:37,320 --> 00:44:40,160
Speaker 1: electron to predict whether it's going to leave the Earth

891
00:44:40,239 --> 00:44:42,840
Speaker 1: or not, or what pass is going to take around

892
00:44:42,880 --> 00:44:45,520
Speaker 1: the Earth, but when you get down to the microscopic level,

893
00:44:45,840 --> 00:44:46,719
Speaker 1: you don't know what to do.

894
00:44:46,840 --> 00:44:49,960
Speaker 2: Yeah, when the quantum nature of those particles is important,

895
00:44:50,360 --> 00:44:52,759
Speaker 2: general relativity breaks down, we don't know what to do

896
00:44:52,840 --> 00:44:55,560
Speaker 2: with it there, and that's exactly where we also can't

897
00:44:55,600 --> 00:44:58,600
Speaker 2: detect the effects of general relativity. If you ignore the

898
00:44:58,640 --> 00:45:01,480
Speaker 2: quantum nature of the electron or the atom, then yes,

899
00:45:01,560 --> 00:45:04,440
Speaker 2: you can use general relativity or even Newtonian physics to

900
00:45:04,520 --> 00:45:07,520
Speaker 2: predict the path of the particle. But when the quantum

901
00:45:07,640 --> 00:45:10,240
Speaker 2: nature is important, that's when it breaks down, and that's

902
00:45:10,520 --> 00:45:13,239
Speaker 2: when we can't detect the effects of general relativity.

903
00:45:14,880 --> 00:45:16,960
Speaker 1: All right, well, what are some of the other extreme

904
00:45:17,040 --> 00:45:19,960
Speaker 1: situations where you think, I think theory might burong.

905
00:45:20,200 --> 00:45:22,720
Speaker 2: The other famous concern, and the one that Listeners raised,

906
00:45:22,920 --> 00:45:26,759
Speaker 2: is singularities. What's inside a black hole? General relativity tells

907
00:45:26,840 --> 00:45:28,880
Speaker 2: us that the things that fall past the event horizon

908
00:45:29,320 --> 00:45:32,800
Speaker 2: slide towards the center of the black hole, where curvature

909
00:45:32,880 --> 00:45:35,440
Speaker 2: gets stronger and stronger, and it gets so strong that

910
00:45:35,560 --> 00:45:39,400
Speaker 2: essentially it's a runaway effect and becomes infinitely dense. You

911
00:45:39,480 --> 00:45:42,160
Speaker 2: have this point in space where you have mass but

912
00:45:42,560 --> 00:45:45,839
Speaker 2: zero volume, and so we call that a singularity because

913
00:45:45,880 --> 00:45:49,520
Speaker 2: the density is essentially infinite or undefined. So that's the

914
00:45:49,520 --> 00:45:52,480
Speaker 2: prediction of general relativity. But most people think that that's

915
00:45:52,520 --> 00:45:55,160
Speaker 2: not really a prediction that's a sign that the theory

916
00:45:55,320 --> 00:45:59,200
Speaker 2: is broken. It's predicting something we think is unphysical and

917
00:45:59,239 --> 00:46:01,319
Speaker 2: it has to be replaced by another theory. That we've

918
00:46:01,320 --> 00:46:04,680
Speaker 2: gone beyond the boundary of where the theory is valid.

919
00:46:05,040 --> 00:46:07,600
Speaker 2: Just like me predicting that I'll grow another meter and

920
00:46:07,640 --> 00:46:09,279
Speaker 2: a half in the next half of my life.

921
00:46:09,760 --> 00:46:11,439
Speaker 1: What do you mean, Like you're saying that the idea

922
00:46:11,440 --> 00:46:15,800
Speaker 1: of a singularity is the prediction of general relativity. Exactly,

923
00:46:16,360 --> 00:46:17,879
Speaker 1: which is at the center of a black hole?

924
00:46:17,960 --> 00:46:20,440
Speaker 2: Yeah, exactly, that's what general relativity tells us is at

925
00:46:20,440 --> 00:46:23,360
Speaker 2: the center of a black hole. But we don't believe it.

926
00:46:23,400 --> 00:46:25,719
Speaker 2: We don't think it's actually there. We think it's a

927
00:46:25,760 --> 00:46:28,799
Speaker 2: sign that general relativity is wrong, that we've pushed it

928
00:46:29,120 --> 00:46:31,479
Speaker 2: beyond the bounds where you can no longer really use

929
00:46:31,560 --> 00:46:32,080
Speaker 2: the theory.

930
00:46:32,360 --> 00:46:35,120
Speaker 1: But why not, Why couldn't you have some point something

931
00:46:35,160 --> 00:46:36,399
Speaker 1: in the center of a black hole.

932
00:46:36,640 --> 00:46:39,720
Speaker 2: Well, one reason is quantum mechanics. Right, if something becomes

933
00:46:39,840 --> 00:46:43,640
Speaker 2: that small, then its quantum properties are important because quantum

934
00:46:43,640 --> 00:46:46,360
Speaker 2: mechanics rules when things are super dup or small. Everything

935
00:46:46,360 --> 00:46:48,560
Speaker 2: in the universe that's super tiny follows the rules of

936
00:46:48,640 --> 00:46:52,280
Speaker 2: quantum mechanics and quantum mechanics says you can't have something

937
00:46:52,400 --> 00:46:55,600
Speaker 2: so massive, so much energy in such a tiny little space,

938
00:46:55,640 --> 00:46:59,040
Speaker 2: as like an inherent fuzziness to the universe that a

939
00:46:59,120 --> 00:47:01,800
Speaker 2: singularity violates. And so if we could look inside a

940
00:47:01,840 --> 00:47:04,160
Speaker 2: black hole and see what's there. Is it a singularity,

941
00:47:04,440 --> 00:47:07,279
Speaker 2: is it something else, a weird quantum fuzzy blob, is

942
00:47:07,280 --> 00:47:10,239
Speaker 2: it something completely different, then we would know how to

943
00:47:10,480 --> 00:47:13,800
Speaker 2: update and correct general relativity. But of course we can't.

944
00:47:14,040 --> 00:47:16,239
Speaker 1: But isn't it sort of the same as like an electron.

945
00:47:16,320 --> 00:47:18,480
Speaker 1: Like an electron you can treat as a point particle,

946
00:47:18,480 --> 00:47:21,239
Speaker 1: which is also an impossibility. And yet do you still

947
00:47:21,239 --> 00:47:23,560
Speaker 1: assume that in quantum mechanics, In sort.

948
00:47:23,360 --> 00:47:25,560
Speaker 2: Of old school quantum mechanics, we do treat the electron

949
00:47:25,600 --> 00:47:28,480
Speaker 2: as a point particle, and that's valid in some scenarios

950
00:47:28,560 --> 00:47:30,600
Speaker 2: right where it doesn't really matter. But you're right, if

951
00:47:30,640 --> 00:47:33,200
Speaker 2: you zoom in on the electron, it can't actually be

952
00:47:33,440 --> 00:47:36,640
Speaker 2: a point particle. And if you do quantum field theory,

953
00:47:36,680 --> 00:47:39,160
Speaker 2: then you replace this idea of a point particle with

954
00:47:39,239 --> 00:47:42,120
Speaker 2: like a little blob of energy density in the quantum

955
00:47:42,239 --> 00:47:45,560
Speaker 2: field of the electron. And so we have like different

956
00:47:45,600 --> 00:47:49,319
Speaker 2: pictures for sort of different scales of work in particle physics.

957
00:47:49,600 --> 00:47:51,560
Speaker 2: But you're right, from some points of view, the point

958
00:47:51,560 --> 00:47:54,239
Speaker 2: particle description works just fine. And so if like from

959
00:47:54,280 --> 00:47:56,560
Speaker 2: the outside of a black hole, having a singularity on

960
00:47:56,600 --> 00:47:59,520
Speaker 2: the inside is okay. But once you zoom in on

961
00:47:59,600 --> 00:48:02,080
Speaker 2: it that you get in and observe the quantum details

962
00:48:02,120 --> 00:48:04,759
Speaker 2: of it, we're wondering like, is it really a singularity

963
00:48:04,840 --> 00:48:07,239
Speaker 2: or is it something else? And that would be a

964
00:48:07,280 --> 00:48:11,120
Speaker 2: deviation from Einstein's prediction. If it's not a singularity, then

965
00:48:11,160 --> 00:48:13,000
Speaker 2: that would be a clue something we could pull on

966
00:48:13,080 --> 00:48:15,880
Speaker 2: to help unravel or update Einstein's theory.

967
00:48:16,920 --> 00:48:18,440
Speaker 1: Well, I feel like in this case, you know, it

968
00:48:18,440 --> 00:48:22,399
Speaker 1: wouldn't prove that Eystein was wrong. It's just that at

969
00:48:22,400 --> 00:48:24,520
Speaker 1: that level you have to use a different set of rules.

970
00:48:24,640 --> 00:48:26,879
Speaker 2: Yeah, that's a good point. It's not showing Einstein is wrong.

971
00:48:26,920 --> 00:48:30,600
Speaker 2: It's showing that his theory is valid only under certain circumstances.

972
00:48:30,960 --> 00:48:33,680
Speaker 2: And that's cool. It's like saying, you know, as fluid

973
00:48:33,719 --> 00:48:36,520
Speaker 2: mechanics wrong, Well, it works great for fluids. You can't

974
00:48:36,520 --> 00:48:39,800
Speaker 2: apply it to like crowds or to steam or crystals.

975
00:48:39,800 --> 00:48:42,560
Speaker 2: Doesn't mean it's wrong. It means that it's relevant to

976
00:48:42,640 --> 00:48:46,560
Speaker 2: a certain set of conditions, And so that's sort of

977
00:48:46,600 --> 00:48:49,279
Speaker 2: the question we were asking philosophically, Like, if Einstein's theory

978
00:48:49,320 --> 00:48:52,640
Speaker 2: of gravity is deeply true, it's the actual story of

979
00:48:52,640 --> 00:48:55,560
Speaker 2: what the universe is doing, then it should always be right.

980
00:48:55,960 --> 00:48:58,040
Speaker 2: But if it's just an approximation, if it's just something

981
00:48:58,080 --> 00:49:02,239
Speaker 2: that works under some certain conditions like fluid mechanics, then

982
00:49:02,320 --> 00:49:04,160
Speaker 2: you know, it's just a story we're telling ourselves that

983
00:49:04,239 --> 00:49:06,520
Speaker 2: helps us do calculations. It might not be like the

984
00:49:06,560 --> 00:49:09,960
Speaker 2: actual story of the universe if there are bounds on

985
00:49:10,080 --> 00:49:11,560
Speaker 2: where it's relevant.

986
00:49:11,400 --> 00:49:13,719
Speaker 1: Or I wonder if another possibilities that it is right

987
00:49:13,800 --> 00:49:16,200
Speaker 1: all the way down to the center of the universe.

988
00:49:16,640 --> 00:49:19,880
Speaker 1: You just have to add quantum mechanics on top, meaning

989
00:49:19,880 --> 00:49:21,279
Speaker 1: that they're each right in their own way.

990
00:49:21,680 --> 00:49:24,160
Speaker 2: Yeah, but they disagree about what happens at the heart

991
00:49:24,200 --> 00:49:26,680
Speaker 2: of a black hole, right, so they can't both be right.

992
00:49:26,960 --> 00:49:29,000
Speaker 1: I don't know. Maybe they don't disagree.

993
00:49:29,600 --> 00:49:32,680
Speaker 2: But they do. They disagree. You know, there might be

994
00:49:32,719 --> 00:49:36,760
Speaker 2: some version of quantum gravity, an extension of Einstein's idea

995
00:49:36,840 --> 00:49:41,399
Speaker 2: modification of Einstein's ideas that describes more accurately what's going

996
00:49:41,520 --> 00:49:45,319
Speaker 2: on inside a black hole. But if there's no singularity. There,

997
00:49:45,360 --> 00:49:46,959
Speaker 2: then Einstein's prediction is wrong.

998
00:49:48,120 --> 00:49:51,360
Speaker 1: Well, as a particle physicist and a quantum mechanic person,

999
00:49:51,840 --> 00:49:53,440
Speaker 1: I would say, maybe you're a little biased.

1000
00:49:53,880 --> 00:49:57,640
Speaker 2: Yeah, yeah, sure, I believe.

1001
00:49:57,360 --> 00:50:00,200
Speaker 1: It all right. What are some of the other situation

1002
00:50:00,320 --> 00:50:02,399
Speaker 1: where you think Einstein might be wrong?

1003
00:50:02,840 --> 00:50:06,239
Speaker 2: Well, another famous singularity is the Big Bang. You know,

1004
00:50:06,280 --> 00:50:08,359
Speaker 2: if you take the universe as we see it, it's

1005
00:50:08,400 --> 00:50:12,040
Speaker 2: sort of cold and dilute, but we see that it's expanding.

1006
00:50:12,280 --> 00:50:14,760
Speaker 2: Then you rewind the clock back to the early universe.

1007
00:50:14,760 --> 00:50:17,360
Speaker 2: You see the universe getting hotter and hotter and denser

1008
00:50:17,400 --> 00:50:20,239
Speaker 2: and denser and denser, and you could rewind that back,

1009
00:50:20,360 --> 00:50:24,600
Speaker 2: like all the way back to an infinite density, a singularity,

1010
00:50:24,640 --> 00:50:27,720
Speaker 2: a moment when the universe is filled with infinitely dense matter.

1011
00:50:28,400 --> 00:50:30,360
Speaker 2: And I gotta clarify a lot of people think of

1012
00:50:30,440 --> 00:50:33,160
Speaker 2: the Big Bang as like a single point of matter

1013
00:50:33,200 --> 00:50:36,520
Speaker 2: which then exploded out into space. But instead we imagine

1014
00:50:36,520 --> 00:50:38,560
Speaker 2: the Big Bang is something that happened everywhere that the

1015
00:50:38,600 --> 00:50:42,840
Speaker 2: whole universe filled with this incredibly dense matter. So Einstein's

1016
00:50:42,840 --> 00:50:45,359
Speaker 2: theory lets you unwind all the way back to this

1017
00:50:45,480 --> 00:50:49,879
Speaker 2: moment of infinite density. But nobody believes that. People think that, well,

1018
00:50:49,960 --> 00:50:52,400
Speaker 2: you get back to some hot dense state up to

1019
00:50:52,440 --> 00:50:55,920
Speaker 2: like the Plank temperature, some really hot moment, and beyond that,

1020
00:50:56,000 --> 00:50:58,440
Speaker 2: some quantum effects are going to be relevant. You can't

1021
00:50:58,480 --> 00:51:01,359
Speaker 2: just use general relativity to extrapolate all the way back

1022
00:51:01,400 --> 00:51:02,799
Speaker 2: to infinite.

1023
00:51:02,280 --> 00:51:06,319
Speaker 1: Density unless quantum mechanics breaks down at that point. Like

1024
00:51:06,920 --> 00:51:10,560
Speaker 1: you're assuming that quantum mechanics is still valid at that point.

1025
00:51:10,360 --> 00:51:13,080
Speaker 2: Right, Yeah, And but quantum mechanics is another theory that's

1026
00:51:13,120 --> 00:51:17,759
Speaker 2: been tested in great detail and very exquisitely, and we

1027
00:51:17,840 --> 00:51:20,840
Speaker 2: think describes the fundamental nature of the universe. So what

1028
00:51:21,080 --> 00:51:24,640
Speaker 2: happens when these two theories come into conflict is the

1029
00:51:24,640 --> 00:51:27,279
Speaker 2: big question. And so, like inside the heart of a

1030
00:51:27,280 --> 00:51:29,839
Speaker 2: black hole or in the very very early universe, these

1031
00:51:29,880 --> 00:51:33,080
Speaker 2: are the moments when quantum mechanics and general relativity are

1032
00:51:33,120 --> 00:51:36,120
Speaker 2: both relevant. They both have something to say about what happens,

1033
00:51:36,200 --> 00:51:39,800
Speaker 2: and they say different things. And so most people believe,

1034
00:51:39,800 --> 00:51:41,719
Speaker 2: and maybe I'm biased because I'm a part of the

1035
00:51:41,800 --> 00:51:44,680
Speaker 2: physicist that the universe is quantum mechanical and that general

1036
00:51:44,719 --> 00:51:47,759
Speaker 2: relativity will break down at those moments and will not

1037
00:51:47,840 --> 00:51:49,360
Speaker 2: accurately predict the universe.

1038
00:51:49,560 --> 00:51:52,040
Speaker 1: I see, by most people you mean you and your friends.

1039
00:51:55,080 --> 00:51:57,760
Speaker 2: Yes, me and the rest of the physicists in the universe.

1040
00:51:58,800 --> 00:52:01,360
Speaker 2: Most people believe that our relativity is wrong, but we

1041
00:52:01,440 --> 00:52:03,839
Speaker 2: haven't proven it. We have not proven it right. It's

1042
00:52:03,880 --> 00:52:06,359
Speaker 2: a belief, it's a theory, it's a speculation.

1043
00:52:06,600 --> 00:52:07,680
Speaker 1: Feels a little like faith.

1044
00:52:07,960 --> 00:52:11,359
Speaker 2: Daniel, Well, you know, science is subjective in the sense

1045
00:52:11,400 --> 00:52:13,640
Speaker 2: of like what we try to believe, what we tried

1046
00:52:13,680 --> 00:52:17,279
Speaker 2: to prove, what we explore. We have hunches, we have creativity.

1047
00:52:17,600 --> 00:52:19,880
Speaker 2: It's not like science is a process that tells you

1048
00:52:19,960 --> 00:52:23,279
Speaker 2: what to try and what experiments to do, et cetera,

1049
00:52:23,320 --> 00:52:26,239
Speaker 2: et cetera. You have to have ideas and intuition and

1050
00:52:26,320 --> 00:52:28,799
Speaker 2: hunches and creativity, but then you have to listen to

1051
00:52:28,840 --> 00:52:31,759
Speaker 2: the experiments, you know, and so that's what we're waiting for.

1052
00:52:32,920 --> 00:52:35,319
Speaker 1: But I guess you would concede that right now. There's

1053
00:52:35,760 --> 00:52:39,000
Speaker 1: nothing that maybe would say that one or the other

1054
00:52:39,080 --> 00:52:41,920
Speaker 1: is right or wrong. You just feel that one is

1055
00:52:42,120 --> 00:52:42,960
Speaker 1: more right than the other.

1056
00:52:43,239 --> 00:52:46,560
Speaker 2: Yeah, we have no evidence that Einstein was wrong. We

1057
00:52:46,719 --> 00:52:49,840
Speaker 2: just suspect very very strongly that he's got to be

1058
00:52:49,880 --> 00:52:53,920
Speaker 2: wrong eventually. But no, we do not have any evidence

1059
00:52:53,920 --> 00:52:54,879
Speaker 2: that Einstein was wrong.

1060
00:52:56,360 --> 00:52:58,720
Speaker 1: In fact, it almost seems like you have the evidence

1061
00:52:58,760 --> 00:52:59,480
Speaker 1: to the contrary.

1062
00:52:59,760 --> 00:53:02,200
Speaker 2: Yeah, we have lots of evidence that he's right. Frustrating

1063
00:53:02,400 --> 00:53:05,400
Speaker 2: the huge amounts of evidence that he was right. But

1064
00:53:05,719 --> 00:53:08,759
Speaker 2: under these scenarios that we can't engineer ourselves. We can't

1065
00:53:08,760 --> 00:53:10,960
Speaker 2: look inside a black hole, we can't rewind time at

1066
00:53:10,960 --> 00:53:13,919
Speaker 2: the beginning of the universe. We have a hard time

1067
00:53:14,000 --> 00:53:16,840
Speaker 2: coming up with ways of testing quantum mechanics and gravity.

1068
00:53:17,080 --> 00:53:19,800
Speaker 2: That we did a whole episode about quantum gravity experiments

1069
00:53:19,800 --> 00:53:22,360
Speaker 2: and a tabletop that might be able to break that barrier.

1070
00:53:22,880 --> 00:53:26,120
Speaker 2: Nobody's yet been able to engineer a scenario to prove

1071
00:53:26,200 --> 00:53:27,040
Speaker 2: Einstein wrong.

1072
00:53:27,160 --> 00:53:29,480
Speaker 1: It kind of feels like a conspiracy theory, Daniel, Is

1073
00:53:29,520 --> 00:53:31,640
Speaker 1: that where the queue in q andon comes from?

1074
00:53:32,040 --> 00:53:35,400
Speaker 2: That does mean quantum Wait? Is Einstein the conspiracy theorist?

1075
00:53:35,520 --> 00:53:37,160
Speaker 2: Or are you saying particle physics?

1076
00:53:38,120 --> 00:53:41,120
Speaker 1: I'm saying maybe quantum mechanics. You can see this is

1077
00:53:41,160 --> 00:53:44,120
Speaker 1: the conspiracy theory. That's where the Q and q andon

1078
00:53:44,239 --> 00:53:45,080
Speaker 1: comes from.

1079
00:53:45,080 --> 00:53:46,400
Speaker 2: Oh I see quantum anon.

1080
00:53:46,520 --> 00:53:49,640
Speaker 1: Yes, yeah, In fact, even sounds like a particle like

1081
00:53:49,719 --> 00:53:55,000
Speaker 1: electrode q and on. Oh man, I just broke the conspiracy.

1082
00:53:55,840 --> 00:53:59,080
Speaker 1: It's all tied secret Cabala physicists.

1083
00:53:59,400 --> 00:54:01,320
Speaker 2: Yeah, that's the exactly right. Well, you could make the

1084
00:54:01,320 --> 00:54:03,640
Speaker 2: same arguments in the other direction, right, you could say, like, look,

1085
00:54:03,680 --> 00:54:06,760
Speaker 2: quantum mechanics has been proven right through a huge number

1086
00:54:06,840 --> 00:54:10,239
Speaker 2: of experiments, but it conflicts with general relativity the heart

1087
00:54:10,280 --> 00:54:13,160
Speaker 2: of black holes in the early universe, so maybe it's wrong.

1088
00:54:13,520 --> 00:54:16,439
Speaker 2: You could take that entirely other perspective. We have two

1089
00:54:16,520 --> 00:54:20,239
Speaker 2: great theories that disagree, and one of them's got to

1090
00:54:20,280 --> 00:54:20,960
Speaker 2: be wrong.

1091
00:54:21,120 --> 00:54:23,120
Speaker 1: Right, I'm just saying, probably we don't know that conspiracy

1092
00:54:23,280 --> 00:54:26,440
Speaker 1: starts with a que and so that to me is

1093
00:54:26,480 --> 00:54:31,640
Speaker 1: a big hint. It sounds like a particle too. All right, Well,

1094
00:54:31,200 --> 00:54:33,440
Speaker 1: what does it all mean, Daniel, doesn't mean that we

1095
00:54:33,480 --> 00:54:37,680
Speaker 1: have these two titanic gigantic theories about the universe. You're

1096
00:54:37,719 --> 00:54:40,440
Speaker 1: saying that the conflict in a lot of situations. So

1097
00:54:40,880 --> 00:54:43,799
Speaker 1: there's plenty of scientific evidence that for each of them

1098
00:54:43,840 --> 00:54:46,520
Speaker 1: to be both right. But they can both be right

1099
00:54:47,120 --> 00:54:48,520
Speaker 1: in the center of the universe.

1100
00:54:48,680 --> 00:54:51,160
Speaker 2: Yeah, we have so many scenarios where we've tested each

1101
00:54:51,200 --> 00:54:55,480
Speaker 2: of them individually with great precision, and all the scenarios

1102
00:54:55,480 --> 00:54:57,640
Speaker 2: where both of them should be relevant are scenarios we

1103
00:54:57,760 --> 00:55:00,799
Speaker 2: can't engineer, or we can't study or hit from us.

1104
00:55:01,239 --> 00:55:03,960
Speaker 2: So it's endlessly frustrating, but there's a lot of creative

1105
00:55:03,960 --> 00:55:06,440
Speaker 2: people out there coming up with ideas for how we

1106
00:55:06,520 --> 00:55:08,959
Speaker 2: might be able to test them, new ways to bring

1107
00:55:09,000 --> 00:55:11,840
Speaker 2: these two theories together. It's been one hundred years. We

1108
00:55:11,880 --> 00:55:15,720
Speaker 2: haven't figured this out, but we're still working on it.

1109
00:55:14,640 --> 00:55:18,479
Speaker 2: M Is it possible they're both right. They can't really

1110
00:55:18,520 --> 00:55:21,480
Speaker 2: both be right because they make different predictions about the

1111
00:55:21,520 --> 00:55:25,640
Speaker 2: same scenarios, but they could both be wrong. In fact,

1112
00:55:25,719 --> 00:55:28,399
Speaker 2: most likely scenario is that they're both wrong and there's

1113
00:55:28,400 --> 00:55:31,400
Speaker 2: some other deeper theory which tells us a completely different

1114
00:55:31,440 --> 00:55:33,840
Speaker 2: story about the nature of the universe. You know, one

1115
00:55:33,880 --> 00:55:35,880
Speaker 2: of my favorite things about these theories is that they

1116
00:55:35,880 --> 00:55:38,640
Speaker 2: do tell a story. There's an explanation for why things happen.

1117
00:55:39,000 --> 00:55:41,600
Speaker 2: But as these theories are replaced by other theories, you

1118
00:55:41,640 --> 00:55:44,120
Speaker 2: get a different story, like, oh, it's not actually fields

1119
00:55:44,120 --> 00:55:46,920
Speaker 2: out there or a curvature of space time, it's something

1120
00:55:46,920 --> 00:55:50,480
Speaker 2: else going on that explains the whole universe. So yeah,

1121
00:55:50,480 --> 00:55:52,080
Speaker 2: I want to be around when we figure that all

1122
00:55:52,080 --> 00:55:54,399
Speaker 2: out and we hear the next story of the true

1123
00:55:54,480 --> 00:55:55,480
Speaker 2: nature of the universe.

1124
00:55:55,719 --> 00:55:57,600
Speaker 1: Pretty cool. It might be that the universe is made

1125
00:55:57,600 --> 00:56:03,000
Speaker 1: out of qnons man and then hey, it'll turn out

1126
00:56:03,040 --> 00:56:03,839
Speaker 1: the Internet was right.

1127
00:56:04,440 --> 00:56:05,800
Speaker 2: I think it's bigfoot particles.

1128
00:56:05,840 --> 00:56:09,279
Speaker 1: Einstein was wrong, Newton was wrong. The Internet was right

1129
00:56:09,360 --> 00:56:09,920
Speaker 1: all along.

1130
00:56:10,239 --> 00:56:12,600
Speaker 2: It's all tiny big foots at the microscopic scale. Yes,

1131
00:56:12,680 --> 00:56:15,800
Speaker 2: that's right, yeah, pulling and pushing. Wait, Sasquatch has a

1132
00:56:15,880 --> 00:56:17,239
Speaker 2: Q in it doesn't it? Oh?

1133
00:56:17,280 --> 00:56:20,359
Speaker 1: It does? Yeah? Oh my, well I also has an

1134
00:56:20,480 --> 00:56:22,960
Speaker 1: S and a couple of a's.

1135
00:56:24,400 --> 00:56:25,440
Speaker 2: Details details.

1136
00:56:25,600 --> 00:56:28,880
Speaker 1: Maybe Sasquatch is a retired engineer and she'll break the

1137
00:56:28,960 --> 00:56:29,680
Speaker 1: whole case open.

1138
00:56:29,680 --> 00:56:29,839
Speaker 2: There.

1139
00:56:30,000 --> 00:56:31,840
Speaker 1: You just have to read past the fifteen minutes Daniel

1140
00:56:32,080 --> 00:56:35,680
Speaker 1: of that email Sasquatch sent you all right, Well, we

1141
00:56:35,760 --> 00:56:38,920
Speaker 1: hope you enjoyed that. Thanks for joining us. See you

1142
00:56:38,920 --> 00:56:39,399
Speaker 1: next time.

1143
00:56:44,040 --> 00:56:47,240
Speaker 2: For more science and curiosity, come find us on social media,

1144
00:56:47,320 --> 00:56:51,880
Speaker 2: where we answer questions and post videos. We're on Twitter, Discord, Instant,

1145
00:56:51,960 --> 00:56:55,400
Speaker 2: and now TikTok. Thanks for listening, and remember that Daniel

1146
00:56:55,440 --> 00:56:58,880
Speaker 2: and Jorge Explain the Universe is a production of iHeartRadio.

1147
00:56:59,160 --> 00:57:03,040
Speaker 2: For more podcast asked from iHeartRadio, visit the iHeartRadio app,

1148
00:57:03,320 --> 00:57:06,800
Speaker 2: Apple Podcasts, or wherever you listen to your favorite shows