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Speaker 1: Welcome to Stuff to Blow Your Mind from how Stuff

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Speaker 1: Works dot com. Hey, welcome to Stuff to Blow your Mind.

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Speaker 1: My name is Robert Lamb and I'm Joe McCormick, and

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Speaker 1: you are here. We're here. It's part three of our

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Speaker 1: exploration of black holes. Now. I think this all came about, Robert,

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Speaker 1: because you went to the World Science Festival and saw

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Speaker 1: a great presentation on black holes. In't that right? Yes,

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Speaker 1: it was called Darkness Visible, Shedding New Light on black Holes.

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Speaker 1: It's a tremendous presentation. It's available on YouTube for your viewing,

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Speaker 1: and I'll make sure that there is a link to

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Speaker 1: it on the landing page for this episode. It's Stuff

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Speaker 1: to Blow your Mind dot com. Now, it's funny. This

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Speaker 1: is gonna be our third episode in a row on

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Speaker 1: black holes, and this will be the last one for now.

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Speaker 1: We will probably revisit the subject again in the future,

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Speaker 1: because even in three whole episodes, there's no way to

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Speaker 1: even come close to exploring all of the interesting stuff

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Speaker 1: about black holes. But we're here for part three. In

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Speaker 1: the first part, we explored the sort of the idea

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Speaker 1: history of black holes, like where they came from conceptually

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Speaker 1: before anybody had ever looked up and seen one. And

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Speaker 1: then in the second episode we tried to talk about

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Speaker 1: ways of inferring the physical existence of black holes, not

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Speaker 1: just the theoretical framework underlying them, but how we can

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Speaker 1: detect them out there in the universe. And then in

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Speaker 1: today's episode, we wanted to sort of like, uh, just

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Speaker 1: do a grab bag of interesting outstanding questions about black

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Speaker 1: holes or thought experiments involving what we know about black

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Speaker 1: holes today. Yeah, then we'll get into some sort of

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Speaker 1: sci fi ideas here as well for sure, which, of course,

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Speaker 1: uh brings us back to the topic of cinematic betrayals

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Speaker 1: of black holes. We talked a little bit about the

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Speaker 1: Disney movie The Black Hole. In the previous episodes we

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Speaker 1: talked about Interstellar and how Interstellar is is actually a

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Speaker 1: pretty good um scientific model to look at as far

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Speaker 1: as depictions of black holes in cinema. But then of

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Speaker 1: course there's Event Horizon, Oh is there? This was the

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Speaker 1: Paul W. S Anderson film, arguably in my mind, the

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Speaker 1: best um Paul W. S Anderson film. What would be

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Speaker 1: the other candidate for the best Paul W. S Anderson

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Speaker 1: film one of the Resident Evils, I guess one of

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Speaker 1: the seven or Eight Resident Evils or Mortal Kombat. You

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Speaker 1: know you can go with that. That was his film

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Speaker 1: prior to Event Horizon. No, I don't want to be mean,

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Speaker 1: but to be generous, we could say not this generation's

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Speaker 1: most highbrow filmmaker. Not to say that that that you

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Speaker 1: and I are purely highbrow of Cinnema enthusiasts. No, we

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Speaker 1: love some trash, and boy's Event Horizon some delectable nineties trash.

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Speaker 1: It's it's got funny c g I. It's got get

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Speaker 1: to the Chopper kind of stuff. It's got a great cast. Actually,

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Speaker 1: it's got hilariously bad writing. It's uh yeah, it's solid

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Speaker 1: B movie territory. It certainly is in that it has

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Speaker 1: uh well, I mean for starters. It's it's certainly not

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Speaker 1: a beam of you if when it comes to the

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Speaker 1: amount of money that's enter this thing. But in terms

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Speaker 1: of of of of looking when you look at it

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Speaker 1: as a whole, there are a lot of problems when

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Speaker 1: you but when you look at some of the of

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Speaker 1: the elements that go into making the film, there are

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Speaker 1: a lot of things I like about it. I think

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Speaker 1: the ship looks really cool, this ideal leather punk spaceship, yeah,

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Speaker 1: I mean it looks like a cathedral. They I like

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Speaker 1: how it incorporates some of these, um these these very

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Speaker 1: obvious elements from films like the Shining uh you know,

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Speaker 1: two thousand and one of Space Odyssey Solaris and brings

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Speaker 1: them all to together. I bet you like the soundtrack,

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Speaker 1: don't you. Well. I thought I was gonna like the

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Speaker 1: soundtrack because it's been a long time since I've seen this,

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Speaker 1: like possibly since high school, and I rewatched rewatched it

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Speaker 1: before we went into to to record this episode. The

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Speaker 1: main thing I was remembering here was that, oh yeah,

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Speaker 1: Orbital worked on the soundtrack Orbital of course, or Legends

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Speaker 1: of the electronic genre that for instance there the Orbital

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Speaker 1: too is a classic, and I recommend everyone who's into

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Speaker 1: electronic and ambience you should check it out. They were

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Speaker 1: also on the soundtrack of the Paul ws Anderson film

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Speaker 1: Mortal Kombat. Yeah, so that that soundtrack was pretty awesome

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Speaker 1: back in the day. But you know me, I love

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Speaker 1: a good electronic score. So I went back to View

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Speaker 1: of the Horizon expecting there to be a lot more Orbital,

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Speaker 1: a lot more electronic uh nuance. But the thing is,

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Speaker 1: it's not just an orbital score. It's orbital and Michael Common,

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Speaker 1: and Michael Common brings the the orchestral stuff into this equation,

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Speaker 1: and it really felt like there was far It was

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Speaker 1: a far more traditional film score than I really wanted

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Speaker 1: to hear. It's one of those beat you over the

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Speaker 1: head horror scores, you know, I hope you want some

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Speaker 1: was Yeah. Yeah, so it did not really Uh it

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Speaker 1: did did not really please me on that level. Um,

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Speaker 1: but I you know, I like this. I like the ship,

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Speaker 1: I like some of the horror elements, and the cast

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Speaker 1: is so good that you can forgive a lot of things,

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Speaker 1: like when Sam neil Is is your lead actor, it

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Speaker 1: forgives a lot of sins. And he, arguably, I would argue,

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Speaker 1: plays the best possible pinhead in this true he essentially

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Speaker 1: becomes a cinebyte in this film, and in doing so,

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Speaker 1: he's like he's a cut above any other cinematic cinebyte. Yeah.

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Speaker 1: You could argue that Event Horizon is a very bad movie,

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Speaker 1: but that it might be in a way the best

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Speaker 1: Hell raisor sequel. Yeah, yeah, I would agree with that. Now,

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Speaker 1: of course, that the harder Why are we talking about

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Speaker 1: Event Horizon? As we touched we've discussed already in There's

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Speaker 1: a black Hole episodes. The event horizon is the point

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Speaker 1: at which light cannot escape the gravity of the singularity.

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Speaker 1: It's the point of no return, right, So you've got

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Speaker 1: this incredibly dense core at the middle of a black hole. Say,

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Speaker 1: if your black hole is the remnant of a collapse star.

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Speaker 1: You know, your star goes supernova, blasts a lot of

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Speaker 1: its material out into space, and then it's got this

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Speaker 1: remnant leftover that's very din It's within what's known as

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Speaker 1: short shield radius, and if it's within that radius, it

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Speaker 1: will collapse upon itself in this weird process that even

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Speaker 1: now we're still trying to understand most fully. It will

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Speaker 1: collapse it this way that it looks like it collapses

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Speaker 1: towards infinite density, and it creates this sphere around it

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Speaker 1: where anything that goes inside the sphere never comes out again.

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Speaker 1: It cannot overcome the force of gravity. It just becomes

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Speaker 1: part of the black hole. Right. And in the film

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Speaker 1: Event Arizon, the essential science the argument that is made

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Speaker 1: uh when when Sam Neil's character Like is forced to

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Speaker 1: explain this to the crew of a spaceship who apparently

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Speaker 1: have no idea how space works. Uh. Apparently the Event

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Speaker 1: Horizon spaceship creates an artificial singularity which is then used

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Speaker 1: to open a wormhole of some sort. And that's that's

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Speaker 1: his about is is? Uh? Is detailed as the explanation

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Speaker 1: gets so also they go to Hell? Well, yes, but

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Speaker 1: that's that's how they get there through the wormhole, or

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Speaker 1: the wormhole goes through Hell. I've done a little vague here.

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Speaker 1: So why have we spent so much time talking about

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Speaker 1: Event Horizon. Here's why, because I'm going to argue that

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Speaker 1: I think a scientifically accurate movie about going to a

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Speaker 1: black hole could be scarier than a movie where you

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Speaker 1: need to put hell and demons in there. All right, Well,

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Speaker 1: that that can be the argument we make during the

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Speaker 1: course of this episode for sure. Okay, well, I think

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Speaker 1: we should talk about what would be like if you

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Speaker 1: want to fall into a black hole. Let's say you

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Speaker 1: get a hanker and you're saying, I want to approach

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Speaker 1: infinite density. Hey it's two thousand eighteen. Yeah, you know,

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Speaker 1: I totally understand that desire. I feel flabby, I feel

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Speaker 1: kind of bloated. I'm going for infinite density now, So

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Speaker 1: you say I'm going to fall into a black hole.

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Speaker 1: You've decided to hop into a spaceship, travel out into

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Speaker 1: the universe, and intentionally fly straight into a very big

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Speaker 1: black hole. Now, there are a lot of people who

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Speaker 1: have written about this subject, trying to imagine what it

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Speaker 1: would be like, the subjective experience of approaching a black hole,

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Speaker 1: crossing the event her Eisen, and then falling in. Uh there.

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Speaker 1: I think Neil de grass Tyson actually has a book

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Speaker 1: about it. I haven't read that book, but I've read

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Speaker 1: a bunch of stuff about this. Probably the best explanation

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Speaker 1: I've read, and one of my main sources here is

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Speaker 1: going to be an explanation from the astrophysicist Ethan Siegel,

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Speaker 1: who is astrophysicist and a science blogger. He runs the

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Speaker 1: Starts with a Bang blog. Do you ever read that, Robert?

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Speaker 1: He writes good stuff about astrophysics. Um so, so he's

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Speaker 1: got an exploration here that I think is pretty good.

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Speaker 1: So he says, Okay, you imagine you're approaching a black hole,

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Speaker 1: and if the black hole were the mass of Earth,

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Speaker 1: the sphere that you do you'd be approaching would only

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Speaker 1: be about one centimeter in radius or about two centimeters wide.

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Speaker 1: If the black hole were about the mass of the Sun,

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Speaker 1: the sphere would only be about three kilometers in radius

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Speaker 1: or about six kilometers wide. So the actual spheres of

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Speaker 1: the event horizon that you would see are are much

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Speaker 1: smaller than a lot of the other things you'd encounter

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Speaker 1: out in the universe. That is, unless you're coming up

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Speaker 1: against one of the biggest ones, like say, a super

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Speaker 1: massive black hole. The kinds of that are at the

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Speaker 1: center of galaxies, So as you approach the black hole

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Speaker 1: from a kind of normal orbital distance. One of the

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Speaker 1: funny things is that, first of all, you might not

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Speaker 1: immediately notice anything strange about the gravity. The gravitational influence

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Speaker 1: you would feel would be a lot like approaching or

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Speaker 1: orbiting a star of the same mass. And to reiterate,

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Speaker 1: if a star the size of our Sun were suddenly

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Speaker 1: magically turned into a black hole. Uh and by the way,

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Speaker 1: this would not ever happen in point of fact, because

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Speaker 1: our son is not massive enough to naturally become a

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Speaker 1: black hole. But if you were to buy magic turn

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Speaker 1: it into a black hole of the same mass, Earth

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Speaker 1: would simply continue orbiting. It wouldn't be immediately sucked in

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Speaker 1: or anything. Things would get very weird on Earth but

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Speaker 1: but yeah, we would not be sucked into the black hole. Right.

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Speaker 1: But once you got closer, then things really do start

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Speaker 1: to get weirder, especially when you get very close. So

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Speaker 1: as you approach the black hole, first of all, you

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Speaker 1: would notice that as you get closer, the black back

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Speaker 1: hole gets bigger faster than any normal object would as

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Speaker 1: you approached it. So you might have a normal sense

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Speaker 1: of Okay, I'm flying towards a planet, or I'm flying

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Speaker 1: towards a star. At a certain speed, you can have

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Speaker 1: a pretty predictable rate of its expansion to take up

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Speaker 1: more and more degrees of your field of view. Right

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Speaker 1: as you near a black hole, the black hole actually

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Speaker 1: gets bigger faster than any normal object would because rays

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Speaker 1: of light beaming towards you passing all around the black

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Speaker 1: hole are bent dramatically inward. Now, remember what we'd actually

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Speaker 1: be seeing out there is you'd see sort of a

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Speaker 1: black disc with light warped around it. Remember the short

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Speaker 1: shield radius, the distance from the center of the black

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Speaker 1: hole to the event horizon. Uh. The the event horizon,

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Speaker 1: of course, is the sphere catastrophe, the point beyond which nothing,

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Speaker 1: not even light can escape. And as you approach that sphere.

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Speaker 1: More closely, the apparent short shield radius from your point

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Speaker 1: of view will grow dramatically. A seagull rights that by

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Speaker 1: the time you're about ten schwart shield radii away from

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Speaker 1: the black holes, about ten of the radius of the

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Speaker 1: black hole away from it, it will appear so big

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Speaker 1: that it will blot out your entire forward forward facing

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Speaker 1: view right, so if you're looking toward it, it will

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Speaker 1: be your entire field of view. A normal object of

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Speaker 1: the same size at that distance would only appear to

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Speaker 1: be about the size of your fist at an arm's length.

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Speaker 1: Then you go deeper and you can reach There are

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Speaker 1: several sort of stops along the way. One of the

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Speaker 1: stops you would reach along the way is what's known

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Speaker 1: as the innermost stable circular orbit, or the I s

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Speaker 1: c O. This is sort of the last filling station

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Speaker 1: before you head down to the border. The I s

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Speaker 1: c O is about one point five times the radius

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Speaker 1: of the event horizon, and it's what it sounds like

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Speaker 1: based on the name. It's the closest that particles can

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Speaker 1: orbit the black hole in a stable circle. Go any

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Speaker 1: closer and it's all downhill, pretty much literally. By the

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Speaker 1: time you reach the I s c O. If you

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Speaker 1: face a black hole, you will see nothing but black

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Speaker 1: in the direction of the black hole, and the event

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Speaker 1: horizon will appear to take up your your whole field

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Speaker 1: of view. But here's the crazy part. You keep going

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Speaker 1: down past the I s c OH and of course

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Speaker 1: total blackness will still take up your entire field of

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Speaker 1: view if you look toward the black hole. But here's

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Speaker 1: what happens if you turn around and look away. And

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Speaker 1: I'll explore this in a couple of different ways. First,

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Speaker 1: a scenario one. This is where you imagine it's only

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Speaker 1: you falling in. It's not light or other stuff falling

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Speaker 1: in with you. And this is not how it would

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Speaker 1: probably really be, just to illustrate the gravitational influences involved.

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Speaker 1: If you keep going toward the black hole and you

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Speaker 1: turn back and look away from it as you're falling in,

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Speaker 1: you will see total darkness begin to creep in from

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Speaker 1: every direction as well in the direction you came from.

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Speaker 1: So you're looking backward, and you will see what looks

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Speaker 1: like a membrane of total darkness closing in all around,

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Speaker 1: and your view of the stars the universe will shrink

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Speaker 1: down to a circle in the direction opposite of the

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Speaker 1: black hole. Just try to imagine that your whole view

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Speaker 1: of the universe being bent and crushed down into a

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Speaker 1: shrinking circle that's receding behind you rapidly. Well again it

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Speaker 1: is so I can't imagine that to a certain extent. Yeah,

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Speaker 1: all starlight dies in a shrinking circle. That that's that's

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Speaker 1: in your past like that. But at this point it's

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Speaker 1: important to remember you have not crossed the event horizon yet,

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Speaker 1: you're just approaching it. So at this point, if you

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Speaker 1: were to change your mind and say, hey, I want

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Speaker 1: to get out of here, uh, there is in principle

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Speaker 1: still hope if you have a powerful enough spaceship you

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Speaker 1: could turn around. You could pile it back towards that

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Speaker 1: shrinking circle of starlight and escape the black hole, at

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Speaker 1: least in theory. But it is at this point going

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Speaker 1: to be a really powerful uphill climb against the gravity

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Speaker 1: of the black hole. But let's say, you know, I

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Speaker 1: don't want to escape, I just want to keep falling.

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Speaker 1: So that's what you do. Assuming you keep looking towards

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Speaker 1: that shrinking circle of are light behind you where you

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Speaker 1: came from, it will eventually shrink down to a point

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Speaker 1: like light source as you near the boundary, as you

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Speaker 1: near the event horizon, and right before you cross the

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Speaker 1: event horizon, the light from that point will cycle through

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Speaker 1: an array of colors due to what's known as gravitational

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Speaker 1: blue shifting, so you'll see red than white, than blue.

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Speaker 1: And at this point, all the low frequency radiation in

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Speaker 1: the universe, stuff like the cosmic microwave background, which stuff

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Speaker 1: which is like microwaves and radio waves, not stuff that's

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Speaker 1: normally visible, will shift up because of the blue shift

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Speaker 1: of the electromagnetic spectrum. It'll shift up into the visible spectrum,

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Speaker 1: and you'll actually be able to see the cosmic microwave

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Speaker 1: background as a visible blue with your eyes. Then finally

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Speaker 1: you hit the border. Okay, so you crossed the event horizon.

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Speaker 1: What do you see in this toy scenario where light

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Speaker 1: is not falling in with you, you will see nothing

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Speaker 1: at all. You have entered ultimate darkness and this point

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Speaker 1: there is no escape, no matter what. So let's say

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Speaker 1: you say, no, I changed my mind after I crossed

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Speaker 1: the event horizon. I want to pilot my spaceship back

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Speaker 1: in the direction I came from. So that should be easy, right,

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Speaker 1: You just turn around and you come back in exactly

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Speaker 1: the opposite direction. You've been traveling. Too bad, you can't

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Speaker 1: do it. If you try, you will discover to your

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Speaker 1: great surprise that the direction that used to be the

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Speaker 1: direction you came from is now downhill into the center

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Speaker 1: of the black hole. And in fact, every direction you

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Speaker 1: try to go in is downhill into the center of

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Speaker 1: the black hole. It is the perfect pit. It is

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Speaker 1: a pit in which the only direction is down. You're

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Speaker 1: going into that thing no matter what in any travel

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Speaker 1: you do would only speed your travel towards the center

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Speaker 1: of the thing. That's kind of mind bending to to

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Speaker 1: to think about. But yeah, essentially all all roads lead

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Speaker 1: to Rome at this point. The remaining question is how

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Speaker 1: long does it take you to get to Rome? Right,

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Speaker 1: so you've crossed, you can't go back, how long do

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Speaker 1: you fall before you sort of reach the center of

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Speaker 1: this thing? Seagull rights that quote as you crossed the

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Speaker 1: horizon at the super massive four million solar mass black

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Speaker 1: hole at the galactic center, believe it or not. Despite

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Speaker 1: the fact that we're talking about an event horizon that

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Speaker 1: might be around a light hour in diameter in our

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Speaker 1: reference frame, it would only take around twenty seconds to

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Speaker 1: reach the singularity once you cross the event horizon. Now,

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Speaker 1: remember that first scenario was kind of a toy scenario

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Speaker 1: where light is falling is not falling in with you.

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Speaker 1: That's just to like see what the gravitational effects are.

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Speaker 1: The physics of the effects are on display, But we

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Speaker 1: created a kind of unrealistic scenario. So in reality, you

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Speaker 1: would probably not be approaching and entering a black hole alone,

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Speaker 1: but you'd be approaching and entering along with a huge

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Speaker 1: tide of light and radiation. And this would mean that

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Speaker 1: in reality, your picture of the universe would not shrink

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Speaker 1: to a point behind you as you approached the black hole,

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Speaker 1: but would remain a kind of warped division of the

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Speaker 1: sky following you down through the darkness after you crossed

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Speaker 1: the event horizon, and that light that you would see

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Speaker 1: would be the light that's been sucked toward and into

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Speaker 1: the event horizon with you. But as as we've been

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Speaker 1: talking about before, unless you just assume some kind of

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Speaker 1: technological or magical form of invincibility, it's highly possible given

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Speaker 1: various factors. There are a lot of different ways that

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Speaker 1: a black hole could be but it's highly possible that

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Speaker 1: you would die at pretty much every stage of the

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Speaker 1: scenario would be describing um for several reasons, one of

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Speaker 1: which is what's been classically known as spaghettification. I've certainly

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Speaker 1: heard Neil de grass Tyson speak about this. It's one

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Speaker 1: of the astrophysicists favorite concepts. Uh So, as you approach

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Speaker 1: the center of gravity of smaller classes of black holes,

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Speaker 1: title forces would work you up good and title forces

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Speaker 1: occur when an object is stretched and deformed because of

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Speaker 1: an imbalance of gravitational forces at different parts of the object.

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Speaker 1: We've talked before about Jupiter's moon Io. You know, Io

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Speaker 1: is one of the most I think it might be

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Speaker 1: the most volcanically active object in the Solar System. If

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Speaker 1: it's not the most, it's one of the most. It's

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Speaker 1: got these volcanoes erupting. What's causing all of this heat

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Speaker 1: and and geologic activity inside Io It's believed to be

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Speaker 1: tidal forces of Jupiter acting on the planet that you know, Jupiter.

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Speaker 1: It's close enough to Jupiter that Jupiter is kind of

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Speaker 1: working the planet with its gravity, and so as you're

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Speaker 1: falling into a black hole, a similar kind of working

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Speaker 1: would happen on you. Basically, imagine you're falling feet first

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Speaker 1: into a relatively small black hole. At a certain radius

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Speaker 1: from the black holes center, you would start to notice

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Speaker 1: that the force of gravity pulling your feet is a

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Speaker 1: lot stronger than the force of gravity pulling your head.

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Speaker 1: And since Einstein, we know that the experience of gravity

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Speaker 1: is subjectively equivalent to the experience of acceleration through space. Right.

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Speaker 1: Gravity is just like being in an accelerating room. So

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Speaker 1: imagine you're falling feet first and you discover that your

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Speaker 1: feet are accelerating faster than your head is. If you

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Speaker 1: were otherwise still alive, when this started to happen to you,

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Speaker 1: it would stretch your body out until it ripped into pieces,

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Speaker 1: and then those pieces would get stretched and ripped into

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Speaker 1: smaller and smaller pieces, until you're just kind of a

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Speaker 1: wet carbon particle jelly streaming through toward a point of

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Speaker 1: infinite density. Also worth noting, if you did a cannonball

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Speaker 1: into the singularity, Uh, then all of this would happen.

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Speaker 1: But first, I'm not sure that has any impact in

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Speaker 1: anybody's decision making. Oh, it has a lot of impact.

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Speaker 1: Somebody should work that up that that should be a paper. Yeah,

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Speaker 1: how would the body react? Uh? As a side note,

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Speaker 1: you might have heard me mention smaller black holes here.

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Speaker 1: Why Why did I mention smaller black holes? It's kind

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Speaker 1: of counterintuitive, but actually smaller black holes will tend to

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Speaker 1: kill you faster through tidal forces than larger black holes will.

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Speaker 1: A much larger black hole actually has a more gentle

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Speaker 1: gradient of gravity acceleration. But so we've been imagining one

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Speaker 1: type of way of picturing this awesome event, the what

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Speaker 1: what it's like to pass into a black hole? One

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Speaker 1: of the things that I want to think about is,

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Speaker 1: once you're within the event horizon of a black hole,

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Speaker 1: does it even make sense to talk about you falling

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Speaker 1: into the black hole? To talk about you and the

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Speaker 1: black hole as separate objects if you can literally never

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Speaker 1: leave no matter what, you are no longer an entity

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Speaker 1: separate from the black hole itself. You are part of

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Speaker 1: the black hole, and the black hole is you. That's true.

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Speaker 1: Like you're no longer a denizen of the larger universe.

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Speaker 1: You're denizen of that particular black hole. H and yeah,

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Speaker 1: and arguably a part of its substance. Yeah. So maybe

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Speaker 1: maybe a more transcendent way of thinking about it would

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Speaker 1: be to say, okay, when you fall into a black hole,

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Speaker 1: it doesn't just kill you. You get to become it

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Speaker 1: consolation price. Yeah, alright, On that note, we're going to

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Speaker 1: take a break and when we come back, we will

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Speaker 1: discuss more of the mysteries and wonders within the black hole.

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Speaker 1: Thank alright, we're back now. One of the things I

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Speaker 1: know they talked about in the Darkness Visible event you

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Speaker 1: saw in New York was the relationship between black holes

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Speaker 1: and entropy? What what was the deal here? Alright, I'm

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Speaker 1: gonna I'm gonna attempt to explain all of this and

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Speaker 1: uh and I do just want to advise listeners more

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Speaker 1: than usual that if if this doesn't completely make sense,

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Speaker 1: do check out the talk, because I get to hear

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Speaker 1: a pair of experts discuss it, uh in with more

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Speaker 1: time and with with greater expertise. But but I will

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Speaker 1: attempt to to summarize here. It is astrophysics. It is

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Speaker 1: it is astrophysics, and we are talking about black holes.

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Speaker 1: So one of the more interesting points brought up in

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Speaker 1: the talk was that string theory actually helps us make

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Speaker 1: sense of what's known as the intropy problem with black holes.

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Speaker 1: The basic problem being is that is that how can

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Speaker 1: a black hole be in a high entropy state if

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Speaker 1: everything inside it is super condensed to a state of

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Speaker 1: less entropy than normal matter, whereas the missing entropy and

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Speaker 1: the thing is. According to string theory, you can say, well,

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Speaker 1: the missing the missing intropy can be found in the

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Speaker 1: six microscopic spatial dimensions that exist in addition to the

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Speaker 1: three spatial dimensions that we can observe. And yes, I

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Speaker 1: realize all that kind of may have sounded to some

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Speaker 1: of you, like, uh, like a monologue from Ghostbusters. But

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Speaker 1: but but it does it does make sense. Okay, So

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Speaker 1: basics on string theory. String theory is an unproven hypothetical

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Speaker 1: framework in physics that explain that goes toward explaining the

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Speaker 1: more ultimate nature of our universe. We've got the Standard model,

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Speaker 1: and you've got particles, and you've got energy and all that,

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Speaker 1: and you're like, does something lie underneath all this? What

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Speaker 1: generates its string theory? That the very basic version is

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Speaker 1: that it posits that underneath all of our model of

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Speaker 1: particle physics and everything are these vibrating strings. And these

430
00:22:58,880 --> 00:23:01,639
Speaker 1: strings make up space, time and particles, and they can

431
00:23:01,760 --> 00:23:05,760
Speaker 1: vibrate in different ways that create different kinds of phenomena

432
00:23:05,800 --> 00:23:08,360
Speaker 1: and objects in our universe. Is that is that kind

433
00:23:08,359 --> 00:23:12,000
Speaker 1: of close approximation. Uh, And so under string theory, it's

434
00:23:12,040 --> 00:23:14,600
Speaker 1: this sort of mathematical framework we haven't been able to

435
00:23:14,640 --> 00:23:18,960
Speaker 1: fully test yet, but under this mathematical framework, it is

436
00:23:19,000 --> 00:23:22,320
Speaker 1: believed that there are more dimensions than just the three

437
00:23:22,359 --> 00:23:25,640
Speaker 1: space dimensions and the one time dimension that we observe, right,

438
00:23:25,680 --> 00:23:29,240
Speaker 1: and they're necessary for string theory to work. Um like this,

439
00:23:29,359 --> 00:23:31,359
Speaker 1: this basically emerges from the math. And one of the

440
00:23:31,400 --> 00:23:34,080
Speaker 1: things that that that Brian Green pointed out in the

441
00:23:34,080 --> 00:23:36,760
Speaker 1: World Science Festival talk is that for for a long

442
00:23:36,800 --> 00:23:38,760
Speaker 1: time this was kind of not really a dirty secret

443
00:23:38,760 --> 00:23:40,600
Speaker 1: of string theory, but it was one of those things

444
00:23:40,600 --> 00:23:42,760
Speaker 1: that was necessary by the math. But it wasn't something

445
00:23:42,760 --> 00:23:45,760
Speaker 1: that necessarily they were putting out there first like saying, uh,

446
00:23:45,840 --> 00:23:50,280
Speaker 1: you know, headline six dimensions, additional spatial dimensions. It was

447
00:23:50,320 --> 00:23:53,240
Speaker 1: more like, we have this this this attempt to understand

448
00:23:53,280 --> 00:23:56,840
Speaker 1: the universe and oh, by the way, six dimensional spatial dimensions.

449
00:23:56,920 --> 00:23:58,880
Speaker 1: And we should mention that Brian Green is a big

450
00:23:58,920 --> 00:24:01,720
Speaker 1: fan of string theory, been working on string three for years,

451
00:24:01,760 --> 00:24:05,359
Speaker 1: but not everybody in the physics community is uh. String

452
00:24:05,400 --> 00:24:07,520
Speaker 1: theory has plenty of critics, people who say, you know,

453
00:24:07,600 --> 00:24:10,119
Speaker 1: this is an even science. It's not testable yet, so

454
00:24:10,160 --> 00:24:12,920
Speaker 1: how could you you know? But the people who work

455
00:24:12,920 --> 00:24:15,119
Speaker 1: on it say, well, we're trying to create a theoretical

456
00:24:15,119 --> 00:24:17,479
Speaker 1: framework and maybe sometime in the future we could do

457
00:24:17,560 --> 00:24:20,320
Speaker 1: tests to try to confirm it or disconfirm it. Yes.

458
00:24:20,760 --> 00:24:22,439
Speaker 1: Now the other side of this, of course, is the

459
00:24:22,560 --> 00:24:26,920
Speaker 1: entropy we're talking about. So the second law of thermot

460
00:24:26,960 --> 00:24:31,080
Speaker 1: thermodynamic states that in a natural thermodynamic process, the sum

461
00:24:31,240 --> 00:24:36,320
Speaker 1: of the entropies of the interacting thermodynamic dynamic systems increases,

462
00:24:36,680 --> 00:24:39,720
Speaker 1: So things are going from low intropy to higher entropy. Um.

463
00:24:40,080 --> 00:24:41,959
Speaker 1: The example that Brian Green throws out is that if

464
00:24:41,960 --> 00:24:43,560
Speaker 1: you have a book's worth of page is stacked on

465
00:24:43,600 --> 00:24:47,280
Speaker 1: top of each other in order, uh, that is low entropy,

466
00:24:47,400 --> 00:24:48,879
Speaker 1: and then you throw it into the air and all

467
00:24:48,880 --> 00:24:50,719
Speaker 1: the pages fall on the ground. Well, now it's gone

468
00:24:50,760 --> 00:24:53,280
Speaker 1: to a high entroview state. In the former the low

469
00:24:53,359 --> 00:24:56,600
Speaker 1: entropy state, less information was required to describe it. But

470
00:24:56,680 --> 00:24:59,480
Speaker 1: in the because you just say, oh, well the information

471
00:24:59,520 --> 00:25:02,160
Speaker 1: on page X is on the sixth page, etcetera, you'll

472
00:25:02,200 --> 00:25:05,320
Speaker 1: find them in order in this stack. But now everything

473
00:25:05,760 --> 00:25:08,359
Speaker 1: is in a high entropy state. You need more information

474
00:25:08,400 --> 00:25:11,439
Speaker 1: to tell you where where everything is. You say, okay,

475
00:25:11,480 --> 00:25:15,800
Speaker 1: page six is, well, it's it's over here, um in

476
00:25:15,800 --> 00:25:19,080
Speaker 1: the middle of the field near pages you know, eight

477
00:25:19,119 --> 00:25:22,679
Speaker 1: hundred and page seventy two, that sort of thing with

478
00:25:22,720 --> 00:25:26,560
Speaker 1: a weasel chewin on it. Right, So when we looked

479
00:25:26,600 --> 00:25:29,320
Speaker 1: back to black holes, yeah, you have to account the

480
00:25:29,320 --> 00:25:31,120
Speaker 1: wee but in the weasels moving around, you gotta track

481
00:25:31,160 --> 00:25:33,560
Speaker 1: the weasel. See, it's so much easier to keep track

482
00:25:33,560 --> 00:25:35,960
Speaker 1: of everything when it's just in a stack. This is

483
00:25:36,000 --> 00:25:41,800
Speaker 1: why good housekeeping is essential. So back to black holes. Though,

484
00:25:41,840 --> 00:25:46,119
Speaker 1: when black holes merge, the area of the event horizon

485
00:25:46,480 --> 00:25:51,000
Speaker 1: holds onto the entropy. But there's this lost information. Uh,

486
00:25:51,160 --> 00:25:53,119
Speaker 1: and this is probably it's probably a terrible way of

487
00:25:53,119 --> 00:25:55,760
Speaker 1: thinking about it. So please, you know, don't like really

488
00:25:55,840 --> 00:25:57,840
Speaker 1: hold onto this or make a T shirt out of it.

489
00:25:57,920 --> 00:26:01,439
Speaker 1: But if two circus clowns were to into a single clown,

490
00:26:02,080 --> 00:26:04,800
Speaker 1: you might expect to have a circus clown with twice

491
00:26:04,840 --> 00:26:08,119
Speaker 1: as many articles of clown clothing, twice as many buzzers,

492
00:26:08,560 --> 00:26:11,959
Speaker 1: twice as many flowers and other like clown gimmicks. Right, uh,

493
00:26:12,119 --> 00:26:15,080
Speaker 1: twice as much face paint. But no, there's something missing.

494
00:26:15,160 --> 00:26:17,439
Speaker 1: Where did the missing clown gimmicks go? Where did the

495
00:26:17,440 --> 00:26:21,439
Speaker 1: missing entropy go? Where the missing information go? Or it

496
00:26:21,520 --> 00:26:24,520
Speaker 1: seems to be missing? Uh, seems to be there, seems

497
00:26:24,560 --> 00:26:27,600
Speaker 1: to be a loss of information. Uh. Intropy is supposed

498
00:26:27,600 --> 00:26:29,720
Speaker 1: to increase, but this would seem to be a decrease

499
00:26:29,760 --> 00:26:33,520
Speaker 1: in entropy, which violates that second loft thermo dynamics. And

500
00:26:33,520 --> 00:26:37,639
Speaker 1: then scientists also found an area increase in merging black holes,

501
00:26:37,880 --> 00:26:40,600
Speaker 1: seeming to line up with the increase in entropy. UH.

502
00:26:40,680 --> 00:26:43,919
Speaker 1: The area of the event horizon is somehow holding onto

503
00:26:43,960 --> 00:26:47,240
Speaker 1: the information that's inside the black hole, and Stephen Hawking

504
00:26:47,320 --> 00:26:51,080
Speaker 1: argued that there was a connection between the black hole

505
00:26:51,119 --> 00:26:54,679
Speaker 1: area in intropy. There must be information, but the horizon

506
00:26:54,880 --> 00:26:58,840
Speaker 1: is is featureless. There's no room for information there to

507
00:26:58,880 --> 00:27:01,760
Speaker 1: be deciphered. So if you solve all of this with

508
00:27:01,760 --> 00:27:05,600
Speaker 1: Einstein's equations, the black hole would seem to have zero entropy.

509
00:27:05,720 --> 00:27:07,720
Speaker 1: It would seem to be a perfectly ordered state. But

510
00:27:07,840 --> 00:27:11,680
Speaker 1: that can't be right now. Basically, as Brian Green described

511
00:27:11,680 --> 00:27:14,359
Speaker 1: at the World Science Festival, you have these extra dimensions

512
00:27:14,359 --> 00:27:16,760
Speaker 1: and string theory that emerges kind of a remainder, a

513
00:27:16,840 --> 00:27:20,399
Speaker 1: kind of a problem, and with black holes you have

514
00:27:20,560 --> 00:27:23,879
Speaker 1: this problem of missing introview, and when you combine the two,

515
00:27:24,359 --> 00:27:27,000
Speaker 1: the problems would seem to kind of cancel each other out.

516
00:27:27,600 --> 00:27:31,320
Speaker 1: Uh and in a way but possibly reveal what could

517
00:27:31,359 --> 00:27:33,960
Speaker 1: be going on inside a black hole. It's still a puzzle.

518
00:27:34,000 --> 00:27:35,919
Speaker 1: It's still a big mystery. You know, where does the

519
00:27:35,920 --> 00:27:39,159
Speaker 1: intropy go when the black hole evaporates and uh, it

520
00:27:39,720 --> 00:27:44,240
Speaker 1: radiates particles and this hawking radiation when it vanishes, what

521
00:27:44,280 --> 00:27:47,359
Speaker 1: happens to the information? Uh? All and all of this

522
00:27:47,440 --> 00:27:50,280
Speaker 1: is based on the math, by the way. Um, but

523
00:27:50,440 --> 00:27:53,520
Speaker 1: it's yeah, it's it's it's fascinating. This is another one

524
00:27:53,520 --> 00:27:56,440
Speaker 1: of those areas where where we were chasing the math

525
00:27:56,760 --> 00:28:00,119
Speaker 1: to find the black hole, and we're still chasing the

526
00:28:00,160 --> 00:28:04,520
Speaker 1: math to understand exactly how it's functioning. Yeah, this is

527
00:28:04,560 --> 00:28:07,480
Speaker 1: one of the frontiers of science. I mean, it's an

528
00:28:07,480 --> 00:28:11,280
Speaker 1: exciting realm because it's a place where you've got to

529
00:28:11,320 --> 00:28:16,480
Speaker 1: have this, uh, this sort of clever cooperation between indirect

530
00:28:16,600 --> 00:28:21,440
Speaker 1: kinds of observations from the experimentalists and clever innovations by

531
00:28:21,600 --> 00:28:25,440
Speaker 1: the theorists, the people coming up with the mathematical framework

532
00:28:25,440 --> 00:28:27,800
Speaker 1: in the theory. I mean, you can't like sample a

533
00:28:27,840 --> 00:28:31,160
Speaker 1: black hole and just say, Okay, let's see what's going on. Right,

534
00:28:31,920 --> 00:28:34,600
Speaker 1: So I realized a lot of that is is very

535
00:28:34,600 --> 00:28:38,320
Speaker 1: difficult to relate to the human experience. So I think

536
00:28:38,320 --> 00:28:41,120
Speaker 1: it's time to move on and talk about black holes

537
00:28:41,240 --> 00:28:44,080
Speaker 1: and time. We've talked about like the sort of the

538
00:28:44,240 --> 00:28:48,240
Speaker 1: visual experience and the the spatial experience of approaching and

539
00:28:48,240 --> 00:28:50,520
Speaker 1: then injuring a black hole crossing its event arise, and

540
00:28:51,080 --> 00:28:53,280
Speaker 1: but then there's this whole question about what happens with

541
00:28:53,360 --> 00:28:56,720
Speaker 1: time because we're talking about space time. We're talking about

542
00:28:56,720 --> 00:29:00,600
Speaker 1: an object that warps space time with its incredible math. Yeah. Now,

543
00:29:00,640 --> 00:29:03,200
Speaker 1: one thing that's absolutely true that we know is that

544
00:29:03,280 --> 00:29:08,760
Speaker 1: time is relative. So the outside observers version of what

545
00:29:08,840 --> 00:29:11,200
Speaker 1: happens to you when you enter a black hole might

546
00:29:11,240 --> 00:29:14,640
Speaker 1: be very different than your subjective experience of what happens

547
00:29:14,680 --> 00:29:16,760
Speaker 1: to you when you enter a black hole, because you're

548
00:29:16,760 --> 00:29:19,560
Speaker 1: not experiencing time in the same way. Yeah. Like, one

549
00:29:19,560 --> 00:29:21,360
Speaker 1: of the key things that will touch on again here

550
00:29:21,480 --> 00:29:24,040
Speaker 1: is you talk about these scenarios where one person enters

551
00:29:24,080 --> 00:29:26,760
Speaker 1: the black hole and one person watches from behind the

552
00:29:26,800 --> 00:29:28,240
Speaker 1: one in the front looks back at the one in

553
00:29:28,280 --> 00:29:31,000
Speaker 1: the back. But then you cannot have a third observer

554
00:29:31,600 --> 00:29:34,440
Speaker 1: who can see both inside a black hole and outside

555
00:29:34,440 --> 00:29:37,280
Speaker 1: of the black hole like that. There that once you

556
00:29:37,360 --> 00:29:39,960
Speaker 1: cross the event arise and that's it. Yeah, okay, well

557
00:29:39,960 --> 00:29:41,480
Speaker 1: I think we've got to take a quick break and

558
00:29:41,520 --> 00:29:43,920
Speaker 1: then after that we will come back and explore black

559
00:29:43,920 --> 00:29:49,520
Speaker 1: holes in time than all right, we're back, so key

560
00:29:49,560 --> 00:29:52,920
Speaker 1: and all of this is a phenomenon called time dilation,

561
00:29:53,160 --> 00:29:55,720
Speaker 1: which we've discussed in the show before. This is the

562
00:29:55,760 --> 00:29:58,520
Speaker 1: idea that time passes more slowly the closer you approach

563
00:29:58,600 --> 00:30:01,360
Speaker 1: the speed of light, which of course is an unbreakable

564
00:30:01,360 --> 00:30:04,520
Speaker 1: cosmic speed limit. Now, one thing we need to say there, though,

565
00:30:04,600 --> 00:30:07,520
Speaker 1: is that the What what that means when you say is,

566
00:30:07,600 --> 00:30:09,280
Speaker 1: let's say you get in a spaceship and you approach

567
00:30:09,360 --> 00:30:12,480
Speaker 1: the speed of light, is that time passes more slowly

568
00:30:12,520 --> 00:30:16,800
Speaker 1: relative to other observers for you, Uh, it doesn't necessarily

569
00:30:16,840 --> 00:30:20,160
Speaker 1: mean that you would feel like you're living in slow motion.

570
00:30:20,240 --> 00:30:22,960
Speaker 1: In fact, what it means is that you are living

571
00:30:23,200 --> 00:30:26,240
Speaker 1: in normal time. But say if you get in a spaceship,

572
00:30:26,280 --> 00:30:27,960
Speaker 1: travel at the speed of light or not at the

573
00:30:27,960 --> 00:30:30,040
Speaker 1: speed of light, close to the speed of light, and

574
00:30:30,120 --> 00:30:32,760
Speaker 1: come back even though it felt like time was passing

575
00:30:32,800 --> 00:30:35,440
Speaker 1: normally for you. You might get back to Earth and

576
00:30:35,480 --> 00:30:38,200
Speaker 1: then realize a lot of time has passed on Earth,

577
00:30:38,240 --> 00:30:41,800
Speaker 1: where it seemed like much less time had passed for you. Right,

578
00:30:41,880 --> 00:30:43,480
Speaker 1: And this is one of those things you could say

579
00:30:43,640 --> 00:30:46,280
Speaker 1: is true on Earth as it is in heaven, because

580
00:30:46,320 --> 00:30:49,120
Speaker 1: the the hands of a clock in a speeding train

581
00:30:49,520 --> 00:30:52,480
Speaker 1: are going to move ever so slightly slower than those

582
00:30:52,480 --> 00:30:56,600
Speaker 1: in a stationary On a stationary clock, the difference would

583
00:30:56,760 --> 00:30:59,280
Speaker 1: not be humanly noticeable, but when the train pulled back

584
00:30:59,280 --> 00:31:01,200
Speaker 1: around to the station and the two clocks would be

585
00:31:01,240 --> 00:31:05,040
Speaker 1: off by billions of a second um. If such a

586
00:31:05,120 --> 00:31:10,200
Speaker 1: train could attain nine point nine nine nine percent light speed,

587
00:31:10,600 --> 00:31:13,240
Speaker 1: only one year would pass on board for every two

588
00:31:13,320 --> 00:31:16,000
Speaker 1: hundred and twenty three years back at the train station,

589
00:31:16,240 --> 00:31:18,960
Speaker 1: even though for the passengers it would feel like time

590
00:31:19,040 --> 00:31:20,960
Speaker 1: was moving normally. Right, This would all be a matter

591
00:31:21,000 --> 00:31:23,560
Speaker 1: of like comparing notes and uh and like looking at

592
00:31:23,640 --> 00:31:27,160
Speaker 1: stop watches when you return. That's the thing. But speed

593
00:31:27,240 --> 00:31:29,880
Speaker 1: isn't the only factor that affects time. On a much

594
00:31:29,920 --> 00:31:34,960
Speaker 1: smaller scale, mass also influences time, so time slows down

595
00:31:35,000 --> 00:31:37,840
Speaker 1: the closer you are to the center of a massive object.

596
00:31:37,960 --> 00:31:40,040
Speaker 1: This is something that was explored to great effect in

597
00:31:40,040 --> 00:31:42,680
Speaker 1: the movie Interstellar, which we mentioned earlier. You get really

598
00:31:42,720 --> 00:31:45,760
Speaker 1: close to the supermassive black hole and and you're gonna

599
00:31:45,800 --> 00:31:49,240
Speaker 1: have some real problems sinking up with your person way

600
00:31:49,280 --> 00:31:52,600
Speaker 1: back in the space station. Yeah, indeed. Uh. And and

601
00:31:52,640 --> 00:31:54,160
Speaker 1: you know, based on this, we know that there are

602
00:31:54,200 --> 00:31:56,560
Speaker 1: places in the universe where time speeds up in places

603
00:31:56,600 --> 00:32:00,840
Speaker 1: where it slows down. Uh. Time, as it's often pointed out,

604
00:32:00,960 --> 00:32:03,080
Speaker 1: runs a little bit faster in space than it does

605
00:32:03,160 --> 00:32:06,719
Speaker 1: down on Earth. A clock aboard and orbiting satellite experiences

606
00:32:06,800 --> 00:32:09,640
Speaker 1: time dilation due to both the speed of its orbit

607
00:32:09,840 --> 00:32:13,000
Speaker 1: and it's greater distance from the center of Earth's gravity.

608
00:32:13,080 --> 00:32:15,560
Speaker 1: And we actually do have to make adjustments for this,

609
00:32:15,760 --> 00:32:19,920
Speaker 1: like for GPS satellites, Uh, they need occasional we we

610
00:32:19,960 --> 00:32:24,440
Speaker 1: need to occasionally adjust timekeeping between GPS satellites and what's

611
00:32:24,440 --> 00:32:28,960
Speaker 1: going on on Earth. So so that's the real world

612
00:32:29,560 --> 00:32:32,720
Speaker 1: version of this, like the accessible version of this that

613
00:32:32,800 --> 00:32:35,840
Speaker 1: actually impacts life on Earth. But then there's the Then

614
00:32:35,920 --> 00:32:38,280
Speaker 1: then we return to black holes though, because the closer

615
00:32:39,040 --> 00:32:42,280
Speaker 1: one gets to a black hole, the stronger the gravity

616
00:32:42,280 --> 00:32:44,800
Speaker 1: would be. And this is gonna have a dramatic effect

617
00:32:44,800 --> 00:32:49,040
Speaker 1: on time making a supermassive black hole, in Hawkings words,

618
00:32:49,760 --> 00:32:53,080
Speaker 1: a sort of natural time machine. The trick would be

619
00:32:53,120 --> 00:32:56,040
Speaker 1: to avoid falling in, hitting just the right trajectory and

620
00:32:56,080 --> 00:32:59,240
Speaker 1: your your spaceship or even your time ship. I guess

621
00:32:59,240 --> 00:33:01,480
Speaker 1: it would be at this point it to orbit around

622
00:33:01,560 --> 00:33:06,280
Speaker 1: the event horizon. High speed would keep you stable, but

623
00:33:06,480 --> 00:33:09,360
Speaker 1: time would slow down by half. So you could take

624
00:33:09,440 --> 00:33:13,600
Speaker 1: say a five year journey to travel ten years into

625
00:33:13,640 --> 00:33:16,000
Speaker 1: the future. That might not seem like a lot, but

626
00:33:16,040 --> 00:33:19,000
Speaker 1: it's ultimately the best the universe offers as far as

627
00:33:19,240 --> 00:33:23,080
Speaker 1: time travel goes without getting into the paradox producing feedback

628
00:33:23,160 --> 00:33:26,680
Speaker 1: loop destroying aspects of wormholes. Right now, this would only

629
00:33:26,720 --> 00:33:30,040
Speaker 1: be travel into the future. I think, as we've discussed before,

630
00:33:30,880 --> 00:33:34,960
Speaker 1: when people ask is time travel possible the questions the

631
00:33:35,000 --> 00:33:37,760
Speaker 1: answer to the question seems to me travel into the

632
00:33:37,760 --> 00:33:41,520
Speaker 1: past absolutely not. Travel into the future is not only possible,

633
00:33:41,560 --> 00:33:44,400
Speaker 1: it is known to be real. Yeah, And it gets

634
00:33:44,440 --> 00:33:46,800
Speaker 1: in this weird scenario where someone could say, Hey, you

635
00:33:46,800 --> 00:33:49,480
Speaker 1: wanna you wanna get to let's say it's eighteen now,

636
00:33:49,640 --> 00:33:52,960
Speaker 1: you want to get to the year Yes, all right, Well,

637
00:33:53,200 --> 00:33:55,480
Speaker 1: how how many years do you want to take to

638
00:33:55,520 --> 00:33:57,360
Speaker 1: get there? You want to take the standard ten. Do

639
00:33:57,360 --> 00:33:59,720
Speaker 1: you want to take five? Well, if you want it

640
00:33:59,760 --> 00:34:02,520
Speaker 1: to want to get there in five years, uh, you know,

641
00:34:03,000 --> 00:34:07,880
Speaker 1: uh relativistically, then you're gonna have to jump on this spaceship.

642
00:34:07,960 --> 00:34:10,040
Speaker 1: And all of our physics tells us this would work.

643
00:34:10,640 --> 00:34:15,720
Speaker 1: But that's outside the event horizon. What what's time like? Uh?

644
00:34:15,760 --> 00:34:18,760
Speaker 1: Within the event horizon? Yeah? Does it even make sense

645
00:34:18,840 --> 00:34:23,440
Speaker 1: to say from an outside observer's perspective that anything happens

646
00:34:23,480 --> 00:34:27,000
Speaker 1: inside a black hole? Is that even a meaningful concept?

647
00:34:27,400 --> 00:34:30,360
Speaker 1: I mean, we're it certainly gets into an area where

648
00:34:30,400 --> 00:34:33,359
Speaker 1: these are all decent questions, you know, because you sort

649
00:34:33,360 --> 00:34:35,400
Speaker 1: of you can do this with a sort of physics breakdown.

650
00:34:35,440 --> 00:34:38,200
Speaker 1: But then ultimately, yeah, what does it mean to be

651
00:34:38,239 --> 00:34:40,719
Speaker 1: within the event horizon? Yeah? By the way, I meant

652
00:34:40,760 --> 00:34:42,719
Speaker 1: that not to say that nothing happens. It was just

653
00:34:42,880 --> 00:34:44,879
Speaker 1: I don't actually know the answer to that question. Well,

654
00:34:44,880 --> 00:34:48,000
Speaker 1: I looked into this, and I was reading an article

655
00:34:48,120 --> 00:34:53,000
Speaker 1: on Ask an Astronomer by Harvard physics graduate students Sarah

656
00:34:53,040 --> 00:34:57,000
Speaker 1: Slater and uh and and she had this fascinating nugget.

657
00:34:57,080 --> 00:35:00,080
Speaker 1: She's she's shared that quote. Everyone inside the event to

658
00:35:00,160 --> 00:35:03,640
Speaker 1: horizon is a psychic whoa explain that okay. So she

659
00:35:03,760 --> 00:35:07,680
Speaker 1: points out that outside of the event horizon, there are

660
00:35:07,719 --> 00:35:12,080
Speaker 1: two criteria for remembering something. One it has to have

661
00:35:12,120 --> 00:35:15,200
Speaker 1: been in the past, and two, it has to have

662
00:35:15,320 --> 00:35:18,759
Speaker 1: happened at a distance no more than what light could

663
00:35:18,760 --> 00:35:22,160
Speaker 1: have traveled since it happened. Okay. So that sort of

664
00:35:22,200 --> 00:35:26,960
Speaker 1: means like, we can't remember events that took place farther

665
00:35:27,040 --> 00:35:30,920
Speaker 1: away than the observable universe because it would have taken

666
00:35:31,080 --> 00:35:33,920
Speaker 1: light longer than the history of the universe to cross

667
00:35:34,000 --> 00:35:36,520
Speaker 1: that distance to reach us. There's no way we could

668
00:35:36,520 --> 00:35:39,480
Speaker 1: have that information, right, I mean, this is like basically

669
00:35:39,719 --> 00:35:41,359
Speaker 1: I'm gonna put that on the shelf and say that's

670
00:35:41,360 --> 00:35:45,120
Speaker 1: space and time as it relates to our our ability

671
00:35:45,120 --> 00:35:49,399
Speaker 1: to remember something. But inside the event horizon, things get

672
00:35:49,400 --> 00:35:53,280
Speaker 1: flipped around space and time you could say, become switched.

673
00:35:53,640 --> 00:35:55,200
Speaker 1: So now these are the two These are the two

674
00:35:55,200 --> 00:35:59,200
Speaker 1: criteria within the event horizon for remembering something. One it

675
00:35:59,320 --> 00:36:01,960
Speaker 1: has to have happened farther from the center of the

676
00:36:02,000 --> 00:36:06,319
Speaker 1: black hole, uh than where you are right now. And

677
00:36:06,560 --> 00:36:10,080
Speaker 1: number two, if T is in the letter T is

678
00:36:10,120 --> 00:36:12,680
Speaker 1: the time that it would take light to travel to

679
00:36:12,760 --> 00:36:16,000
Speaker 1: you from the location of the event, then it happened

680
00:36:16,000 --> 00:36:20,080
Speaker 1: either no more than tea hours ago or tea hours

681
00:36:20,160 --> 00:36:23,720
Speaker 1: into the future. So I'm gonna just read this direct

682
00:36:23,840 --> 00:36:27,760
Speaker 1: quote from her quote if you look away from the center.

683
00:36:27,840 --> 00:36:30,920
Speaker 1: And again this goes back to our earlier ideas of

684
00:36:31,080 --> 00:36:34,120
Speaker 1: crossing the event horizon and looking back or trying to

685
00:36:34,160 --> 00:36:36,640
Speaker 1: look back. She says, quote, if you look away from

686
00:36:36,640 --> 00:36:39,840
Speaker 1: the center, though, you can see two images of everything,

687
00:36:40,480 --> 00:36:43,080
Speaker 1: one from tea hours in the past and one from

688
00:36:43,160 --> 00:36:46,439
Speaker 1: tea hours in the future. For nearby objects, these two

689
00:36:46,440 --> 00:36:49,560
Speaker 1: images will look just the same, since t will be

690
00:36:49,680 --> 00:36:52,560
Speaker 1: very small due the due to the large speed of light.

691
00:36:53,040 --> 00:36:56,320
Speaker 1: For far away objects, though, they could be completely different.

692
00:36:56,560 --> 00:36:59,520
Speaker 1: So you could see the past beginning of something and

693
00:36:59,600 --> 00:37:03,520
Speaker 1: it's few your end. At the same time, spacetime is twisted.

694
00:37:04,360 --> 00:37:05,759
Speaker 1: And then there's this. If you were to enter a

695
00:37:05,800 --> 00:37:09,840
Speaker 1: black hole, theoretically speaking, an outside observer might watch you

696
00:37:09,920 --> 00:37:12,279
Speaker 1: crash and burn on the event arise and destroyed by

697
00:37:12,280 --> 00:37:15,480
Speaker 1: all that hawking radiation, all of your information spread out

698
00:37:15,480 --> 00:37:19,560
Speaker 1: across the face of the dark sphere. Uh because again

699
00:37:19,560 --> 00:37:22,520
Speaker 1: the information can't be lost, but your experience would be

700
00:37:22,560 --> 00:37:25,320
Speaker 1: one of free fall for the rest of your life.

701
00:37:25,920 --> 00:37:28,960
Speaker 1: And in short, this is the firewall paradox. Uh, there's

702
00:37:29,000 --> 00:37:32,120
Speaker 1: no third witness who can see both within and without

703
00:37:32,320 --> 00:37:35,560
Speaker 1: the event Arizona. And to me, that's all just mind

704
00:37:35,600 --> 00:37:38,839
Speaker 1: going to try and and uh and and contemplate. Yeah,

705
00:37:38,840 --> 00:37:41,520
Speaker 1: I feel like I'm still trying to understand it. Um.

706
00:37:41,560 --> 00:37:44,520
Speaker 1: I mean it drives home the way that black holes

707
00:37:44,560 --> 00:37:50,040
Speaker 1: are kind of They're great because they are a reality

708
00:37:50,120 --> 00:37:53,880
Speaker 1: that brings to life all of these impossible relativity experiments

709
00:37:53,920 --> 00:37:57,520
Speaker 1: that people try to use to explain how weird spacetime

710
00:37:57,560 --> 00:37:59,719
Speaker 1: really is. One of the things we talked about in

711
00:37:59,719 --> 00:38:01,440
Speaker 1: the last episode is you know, if you were to

712
00:38:01,480 --> 00:38:04,000
Speaker 1: just go based on your intuitions, you'd probably think, well,

713
00:38:04,400 --> 00:38:08,200
Speaker 1: space and time are are fixed, and the speed of

714
00:38:08,320 --> 00:38:11,279
Speaker 1: light is can be moved all around. But in fact

715
00:38:11,320 --> 00:38:14,200
Speaker 1: it's exactly the opposite. Speed of light is fixed speed

716
00:38:14,200 --> 00:38:16,560
Speaker 1: of light and a vacuum is fixed and space and

717
00:38:16,600 --> 00:38:20,239
Speaker 1: time can be stretched all around. And you can't really

718
00:38:20,280 --> 00:38:22,560
Speaker 1: internalize that. But people try to come up with all

719
00:38:22,600 --> 00:38:27,680
Speaker 1: these impossible scenarios to illustrate the principle. At the black hole,

720
00:38:28,239 --> 00:38:30,000
Speaker 1: you don't have to come up with scenarios. This just

721
00:38:30,040 --> 00:38:32,959
Speaker 1: apparently is what black holes do. Now. At this point

722
00:38:32,960 --> 00:38:35,040
Speaker 1: in the podcast, is we're beginning to wind down here,

723
00:38:35,440 --> 00:38:37,520
Speaker 1: I thought it might be fun to just talk about

724
00:38:37,560 --> 00:38:41,160
Speaker 1: a couple of questions that that frequently come up. Either

725
00:38:41,680 --> 00:38:43,840
Speaker 1: some of these we have received as emails from people,

726
00:38:44,040 --> 00:38:45,799
Speaker 1: and then others are just sort of general questions that

727
00:38:45,840 --> 00:38:50,480
Speaker 1: arise from sci fi treatments of black holes, including event Horizon. Okay,

728
00:38:50,480 --> 00:38:52,640
Speaker 1: so the first one is if and I know we've

729
00:38:52,640 --> 00:38:55,560
Speaker 1: received this from listeners, if I'm pulled into a black hole,

730
00:38:55,680 --> 00:38:57,960
Speaker 1: will I then come back out of a white hole?

731
00:38:58,160 --> 00:39:00,080
Speaker 1: And I think sometimes this is an area where we

732
00:39:00,080 --> 00:39:02,080
Speaker 1: we fall into the trap of thinking of black holes

733
00:39:02,120 --> 00:39:06,120
Speaker 1: more as wormholes. But the white hole concept is in

734
00:39:06,200 --> 00:39:09,759
Speaker 1: fact a byproduct of general relativity. But it's even more

735
00:39:09,800 --> 00:39:13,400
Speaker 1: of a mathematical phantom. In many respects, it is the

736
00:39:13,440 --> 00:39:15,640
Speaker 1: reverse of a black hole. It's not a place where

737
00:39:15,719 --> 00:39:18,880
Speaker 1: matter is lost, but rather a place where matter is born.

738
00:39:19,360 --> 00:39:21,759
Speaker 1: I've seen it explained as sort of like the Big

739
00:39:21,800 --> 00:39:25,719
Speaker 1: Bang singularity but not but not quite the same. But

740
00:39:25,840 --> 00:39:29,880
Speaker 1: it also can't actually exist in our universe. Yeah, so

741
00:39:30,120 --> 00:39:32,000
Speaker 1: I hadn't heard this. I've heard the white holes were

742
00:39:32,040 --> 00:39:36,319
Speaker 1: still kind of a speculative possibility. Well, this is, well,

743
00:39:36,920 --> 00:39:39,560
Speaker 1: my understanding of it and again this could be that

744
00:39:39,719 --> 00:39:41,719
Speaker 1: this could be incorrect, and I may have to be

745
00:39:41,840 --> 00:39:47,200
Speaker 1: corrected on this later. But my understand my my understanding

746
00:39:47,200 --> 00:39:49,760
Speaker 1: of it that it is that it emerges from the math.

747
00:39:50,200 --> 00:39:51,680
Speaker 1: But it's one of these things that emerges from the

748
00:39:51,719 --> 00:39:53,720
Speaker 1: math that that we're like, well, that doesn't really square

749
00:39:53,800 --> 00:39:56,799
Speaker 1: up with what we we actually expect to see in

750
00:39:56,840 --> 00:40:02,040
Speaker 1: the universe. Astrophysicist Karen master Is once described it this way, quote,

751
00:40:02,120 --> 00:40:04,719
Speaker 1: there is only such a thing as a white hole

752
00:40:05,120 --> 00:40:07,879
Speaker 1: in the theory of black holes, and no such thing

753
00:40:08,200 --> 00:40:12,239
Speaker 1: is possible, is possible physically. Well, I'm sure she knows

754
00:40:12,239 --> 00:40:14,239
Speaker 1: a million times more about this than I do, but

755
00:40:14,280 --> 00:40:16,880
Speaker 1: I would just point out that that used to be

756
00:40:16,960 --> 00:40:21,040
Speaker 1: what the astronomers said about black holes. Yeah, but I'm

757
00:40:21,080 --> 00:40:23,040
Speaker 1: not using that to say white holes exist. I mean,

758
00:40:23,040 --> 00:40:25,280
Speaker 1: I'm sure she's probably drawing on a lot of facts

759
00:40:25,320 --> 00:40:28,040
Speaker 1: that that I'm not aware of my But basically, my

760
00:40:28,040 --> 00:40:31,080
Speaker 1: my read from this information is that the answer to

761
00:40:31,200 --> 00:40:32,839
Speaker 1: if if I go into a black hole, I come

762
00:40:32,840 --> 00:40:36,279
Speaker 1: out a white hole, the answer is is probably no.

763
00:40:36,920 --> 00:40:40,600
Speaker 1: And probably you're thinking more about a wormhole here, You're

764
00:40:40,600 --> 00:40:43,520
Speaker 1: not really you're not really picturing what a black hole

765
00:40:43,640 --> 00:40:47,279
Speaker 1: and indeed, a white hole would actually be well, I'm

766
00:40:47,440 --> 00:40:50,040
Speaker 1: more I'm inclined to take the astrophysicists word on it,

767
00:40:50,160 --> 00:40:53,160
Speaker 1: so so I'll go with that. No, no white holes. Okay.

768
00:40:53,280 --> 00:40:56,920
Speaker 1: So another frequently asked question, and this one's a lot

769
00:40:56,920 --> 00:40:59,279
Speaker 1: more fun I have to have to say, is could

770
00:40:59,280 --> 00:41:01,600
Speaker 1: we one day harness the power of a black hole?

771
00:41:02,120 --> 00:41:05,040
Speaker 1: Perhaps like what we see an event horizon, it's a

772
00:41:05,080 --> 00:41:08,160
Speaker 1: black hole. Drive tell me event horizon as possible. Kay,

773
00:41:08,360 --> 00:41:11,279
Speaker 1: let's hear it. Okay, So, first of all, this is

774
00:41:11,280 --> 00:41:13,640
Speaker 1: probably a good time to refresh everyone on the Kardashian scale,

775
00:41:13,719 --> 00:41:17,160
Speaker 1: which we referenced earlier. This is the idea that this

776
00:41:17,200 --> 00:41:19,520
Speaker 1: is just like a very rough way of understanding like

777
00:41:19,520 --> 00:41:25,239
Speaker 1: what would be the technological levels of possible um civilizations

778
00:41:25,360 --> 00:41:28,040
Speaker 1: in the universe. And it's judge based on how much

779
00:41:28,160 --> 00:41:31,120
Speaker 1: energy you can take control of, right and like truly

780
00:41:31,160 --> 00:41:34,200
Speaker 1: take control of. So, for instance, Type one civilizations are

781
00:41:34,239 --> 00:41:37,160
Speaker 1: masters of planetary energy, meaning they can harness this some

782
00:41:37,440 --> 00:41:40,719
Speaker 1: energy of an entire world. We're not there yet, no,

783
00:41:40,880 --> 00:41:43,759
Speaker 1: we would still be a type zero civilization. Type to

784
00:41:43,920 --> 00:41:47,560
Speaker 1: civilizations can summon the power of an entire star system,

785
00:41:47,600 --> 00:41:49,880
Speaker 1: and those would be I mean these would be godlike

786
00:41:50,000 --> 00:41:52,360
Speaker 1: entities if we were to encounter them, if I remember correctly,

787
00:41:52,440 --> 00:41:55,799
Speaker 1: like the the the aliens we encounter in two thousand

788
00:41:55,840 --> 00:41:59,319
Speaker 1: and one Space Odyssey are probably Type two. Yeah, so

789
00:41:59,360 --> 00:42:02,520
Speaker 1: they know you. Dyson's fears would be an example. So

790
00:42:02,560 --> 00:42:05,600
Speaker 1: if you you create a structure that can harness and

791
00:42:05,640 --> 00:42:08,720
Speaker 1: make usable all of the radiation coming off of a star,

792
00:42:10,160 --> 00:42:13,760
Speaker 1: and then Type three civilizations command energy on a galactic scale,

793
00:42:14,080 --> 00:42:17,160
Speaker 1: and that we can't even picture that that's god like

794
00:42:17,360 --> 00:42:19,480
Speaker 1: to a level that it's yeah, I think it's difficult

795
00:42:19,520 --> 00:42:23,279
Speaker 1: for us to even summon. Yeah, it's difficult for me

796
00:42:23,320 --> 00:42:26,000
Speaker 1: to even imagine that as well, it would do because

797
00:42:26,080 --> 00:42:30,120
Speaker 1: Type two civilizations would appear as God's Type three. We

798
00:42:30,600 --> 00:42:32,440
Speaker 1: I don't know, we don't even know they're there. If

799
00:42:32,440 --> 00:42:34,040
Speaker 1: we could, they could be all in the room with us.

800
00:42:34,080 --> 00:42:37,480
Speaker 1: And who are we? Who are we to to to

801
00:42:37,480 --> 00:42:41,080
Speaker 1: to even notice them? So anyway, harvesting the power of

802
00:42:41,120 --> 00:42:43,719
Speaker 1: a black hole sounds exactly like the type of thing

803
00:42:43,840 --> 00:42:48,240
Speaker 1: a Type to civilization would be into um and in fact,

804
00:42:48,320 --> 00:42:51,120
Speaker 1: even a Type zero civilization like our own can think

805
00:42:51,120 --> 00:42:53,960
Speaker 1: of a few ways one might go about it. So

806
00:42:54,120 --> 00:42:57,880
Speaker 1: remember that hawking radiation that we've mentioned already that's emitted

807
00:42:57,880 --> 00:43:01,000
Speaker 1: by a black hole. Well one to harvest that, yeah,

808
00:43:01,120 --> 00:43:06,120
Speaker 1: just turned into a nuclear reactor. Well in, physicist George

809
00:43:06,239 --> 00:43:10,320
Speaker 1: unrou and Robert Wald suggested that one could essentially lower

810
00:43:10,360 --> 00:43:14,160
Speaker 1: a bucket toward the event horizon, collect this radiation, and

811
00:43:14,200 --> 00:43:16,880
Speaker 1: then drawl it back out. Now, if you let the

812
00:43:17,040 --> 00:43:19,480
Speaker 1: bucket go through the event horizon, you would not be

813
00:43:19,480 --> 00:43:21,759
Speaker 1: able to get it back right, Yeah, there's no that

814
00:43:22,719 --> 00:43:25,920
Speaker 1: the light cannot escape, and certainly a type two Kardashian

815
00:43:26,040 --> 00:43:28,080
Speaker 1: bucket would not be able to escape. Right. That would

816
00:43:28,080 --> 00:43:30,640
Speaker 1: be like the black holes. Like the neighbor who you know,

817
00:43:30,680 --> 00:43:35,080
Speaker 1: your frisbee goes in their yard and that's my bucket. Now. Now,

818
00:43:35,480 --> 00:43:38,000
Speaker 1: there's some problems with this though, because the tension of

819
00:43:38,040 --> 00:43:41,000
Speaker 1: the rope here is an issue. Adam Brown of the

820
00:43:41,239 --> 00:43:46,120
Speaker 1: Princeton Center of for the Theoretical Science countered that the

821
00:43:46,239 --> 00:43:49,319
Speaker 1: rope descending towards such high gravity would only be able

822
00:43:49,360 --> 00:43:52,600
Speaker 1: to support its own mass, not the additional mass of

823
00:43:52,680 --> 00:43:56,160
Speaker 1: this mind hawking radiation. Plus, as you know, it also

824
00:43:56,200 --> 00:43:58,399
Speaker 1: needs to be able to withstand the crazy hey heat

825
00:43:58,480 --> 00:44:04,320
Speaker 1: of hawking radiation, as with the bucket. Now in albion

826
00:44:04,400 --> 00:44:08,080
Speaker 1: Lawrence and A. Mill Martinique of the University of Chicago

827
00:44:08,520 --> 00:44:12,640
Speaker 1: proposed that we could instead dip strings into the black

828
00:44:12,680 --> 00:44:17,200
Speaker 1: hole and hawking radiation would climb up out on its own.

829
00:44:17,680 --> 00:44:19,960
Speaker 1: So this would be like I've seen it compared to

830
00:44:20,239 --> 00:44:22,799
Speaker 1: U like the like an oil wick in a in

831
00:44:22,840 --> 00:44:26,839
Speaker 1: an oil lantern. So you're not getting anything back from

832
00:44:26,840 --> 00:44:30,920
Speaker 1: beyond the event horizon, but you're harvesting the hawking radiation

833
00:44:30,960 --> 00:44:33,879
Speaker 1: around it. Yeah, kind of almost like luring it out.

834
00:44:34,840 --> 00:44:36,640
Speaker 1: So you know, this is this is an interesting think

835
00:44:36,640 --> 00:44:38,600
Speaker 1: about and you would be able to to to mind

836
00:44:38,680 --> 00:44:41,520
Speaker 1: just a colossal amount of energy this way. But what

837
00:44:41,640 --> 00:44:45,200
Speaker 1: about doing more of this event horizon model Event Horizon

838
00:44:45,239 --> 00:44:48,800
Speaker 1: the movie? What about actually, you say, capturing a small

839
00:44:48,800 --> 00:44:52,319
Speaker 1: black hole, maybe a primordial black hole, using that to

840
00:44:52,320 --> 00:44:56,120
Speaker 1: power your space or making your own singularity. Well, on

841
00:44:56,120 --> 00:44:58,080
Speaker 1: one hand, that sounds kind of impossible, But on the

842
00:44:58,080 --> 00:45:00,680
Speaker 1: other hand, we should be clear that a black hole

843
00:45:00,920 --> 00:45:03,839
Speaker 1: doesn't have to come from a star in principle at least,

844
00:45:03,920 --> 00:45:06,839
Speaker 1: I mean, we we don't have any technology for like

845
00:45:07,120 --> 00:45:11,080
Speaker 1: making big old black holes. But in order to create

846
00:45:11,120 --> 00:45:12,839
Speaker 1: a black hole, all you have to do is get

847
00:45:12,920 --> 00:45:16,360
Speaker 1: an amount of mass within Swart shield radius. Right. And

848
00:45:16,400 --> 00:45:18,520
Speaker 1: if you can do that, you've made a black hole.

849
00:45:18,520 --> 00:45:21,480
Speaker 1: It doesn't have to be a collapse stellar remnant, right,

850
00:45:21,600 --> 00:45:24,880
Speaker 1: And then arguably you could make one out of energy

851
00:45:24,960 --> 00:45:28,359
Speaker 1: instead of just pure mass. So this is what's known

852
00:45:28,360 --> 00:45:32,759
Speaker 1: as a swart shield. Google blitz, Google blitz, google blitz. Yes,

853
00:45:32,840 --> 00:45:35,600
Speaker 1: sounds like a brand of blender or something, yeah, or

854
00:45:35,719 --> 00:45:38,800
Speaker 1: a delicious breakfast cereal or part of your your complete breakfast.

855
00:45:39,400 --> 00:45:44,200
Speaker 1: So this is the brainchild of theoretical physicist John Archibald

856
00:45:44,200 --> 00:45:48,760
Speaker 1: Wheeler Wheeler and uh, it's the google blitz is German

857
00:45:48,800 --> 00:45:51,399
Speaker 1: for ball lightning. Uh. And the idea is that these

858
00:45:51,400 --> 00:45:54,880
Speaker 1: are These would be concentrations of energy so intense that

859
00:45:54,960 --> 00:45:58,120
Speaker 1: they form their own event horizons and collapse on themselves.

860
00:45:58,719 --> 00:46:01,319
Speaker 1: And it would need for this to work to be

861
00:46:01,520 --> 00:46:05,160
Speaker 1: for this to be something you could actually utilize, it

862
00:46:05,160 --> 00:46:07,719
Speaker 1: would need to be smaller than a proton. It would

863
00:46:07,719 --> 00:46:10,399
Speaker 1: be incredibly hot, but if you could contain it, you'd

864
00:46:10,440 --> 00:46:13,480
Speaker 1: have just immense energy at your disposal. Now, I'm not

865
00:46:13,520 --> 00:46:16,040
Speaker 1: the biggest star Trek the next generation buff I like

866
00:46:16,120 --> 00:46:18,959
Speaker 1: watched all these episodes, I think every evening at nine

867
00:46:19,000 --> 00:46:22,600
Speaker 1: pm back in um in middle school, watched them on syndication,

868
00:46:22,640 --> 00:46:24,799
Speaker 1: But it's been a long time since I've viewed them.

869
00:46:24,920 --> 00:46:27,880
Speaker 1: You went down to the planets, to the pottered plants. Oh, yeah,

870
00:46:27,920 --> 00:46:29,920
Speaker 1: I I think I watched them them all back in

871
00:46:29,960 --> 00:46:31,920
Speaker 1: the day. But there was an episode that I do

872
00:46:31,960 --> 00:46:35,920
Speaker 1: not directly remember, titled Timescape, and it reveals that a

873
00:46:36,000 --> 00:46:39,560
Speaker 1: Romulan warbird is powered by one of these uh sword

874
00:46:39,640 --> 00:46:42,080
Speaker 1: shield google blitz uh and it didn't, but it ends

875
00:46:42,160 --> 00:46:45,160
Speaker 1: up resulting in all these temporal anomalies. Uh. And that's

876
00:46:45,239 --> 00:46:47,359
Speaker 1: you know, the plot of the show is like, what's

877
00:46:47,360 --> 00:46:50,480
Speaker 1: happening to time? Oh, it's something that Romulans did. Um.

878
00:46:50,520 --> 00:46:53,840
Speaker 1: I don't remember it myself, but I've seen it cited

879
00:46:54,000 --> 00:46:57,759
Speaker 1: as a as as an episode that utilizes this concept. Yeah,

880
00:46:57,760 --> 00:46:59,759
Speaker 1: if Wheeler wants to try it out, I'd say let's

881
00:46:59,800 --> 00:47:02,759
Speaker 1: go with Wheeler's I D idea. But I like thinking

882
00:47:02,800 --> 00:47:05,520
Speaker 1: of it. This. What if you create this uh this

883
00:47:05,520 --> 00:47:09,000
Speaker 1: this artificial black hole or this uh this this little

884
00:47:09,040 --> 00:47:11,640
Speaker 1: lightning ball and then you drop it on the floor.

885
00:47:12,160 --> 00:47:13,920
Speaker 1: That's got to be the worst. It's you know, it's

886
00:47:13,960 --> 00:47:17,360
Speaker 1: bad enough when you say, drop a hummingbird feeder onto

887
00:47:17,400 --> 00:47:19,600
Speaker 1: the kitchen floor and you get sugar water everywhere. What

888
00:47:19,640 --> 00:47:22,560
Speaker 1: happens when you drop a black hole that's hard to

889
00:47:22,560 --> 00:47:26,279
Speaker 1: clean up? Here's a hint. It's sticky, And I think

890
00:47:26,320 --> 00:47:30,120
Speaker 1: that sums up the whole episode right there. Well, you know,

891
00:47:30,200 --> 00:47:32,080
Speaker 1: I would say that there's all kinds of other black

892
00:47:32,080 --> 00:47:34,360
Speaker 1: hole stuff we didn't even get to. So maybe we

893
00:47:34,360 --> 00:47:36,320
Speaker 1: can come back again in the future. I just figured

894
00:47:36,320 --> 00:47:38,320
Speaker 1: three episodes in a row, that's a lot. We probably

895
00:47:38,320 --> 00:47:41,160
Speaker 1: shouldn't push it to four this week, I I think,

896
00:47:41,200 --> 00:47:42,759
Speaker 1: so we have to move on to other topics and

897
00:47:42,760 --> 00:47:45,560
Speaker 1: then we can return later because, as we've already touched

898
00:47:45,600 --> 00:47:49,560
Speaker 1: on the the exploration of black holes is ongoing. It

899
00:47:49,680 --> 00:47:52,319
Speaker 1: is far from a closed book. Yeah, we're learning. We're

900
00:47:52,440 --> 00:47:55,520
Speaker 1: learning new stuff about black holes this year, especially with say,

901
00:47:55,520 --> 00:47:58,440
Speaker 1: the research into Sagittarys, a star in the middle of

902
00:47:58,440 --> 00:48:01,440
Speaker 1: our galaxy going on just this year. Yeah. So hey,

903
00:48:01,520 --> 00:48:04,120
Speaker 1: maybe at the end of we can come back and

904
00:48:04,120 --> 00:48:07,080
Speaker 1: we just we can discuss what we know now about

905
00:48:07,800 --> 00:48:11,600
Speaker 1: about singularities that we did not know just a year earlier.

906
00:48:11,640 --> 00:48:13,959
Speaker 1: One of the most interesting things mentioned in that World

907
00:48:13,960 --> 00:48:17,000
Speaker 1: Science Festival event that we keep referring to is the

908
00:48:17,040 --> 00:48:19,879
Speaker 1: idea that observations of black holes that are just now

909
00:48:19,920 --> 00:48:23,600
Speaker 1: coming online, Like what we're finally learning about sagittarys a

910
00:48:23,719 --> 00:48:27,279
Speaker 1: star in fact, seems to be though this could this

911
00:48:27,320 --> 00:48:30,560
Speaker 1: could change, but at least seems in initial observations to

912
00:48:30,640 --> 00:48:34,520
Speaker 1: be challenging some of the findings of general relativity. Yeah,

913
00:48:34,920 --> 00:48:37,000
Speaker 1: so what do you what do you do with that?

914
00:48:37,040 --> 00:48:39,239
Speaker 1: What happens when you do an experiment you think it's

915
00:48:39,239 --> 00:48:42,839
Speaker 1: a well designed experiment, but then it disagrees with Einstein?

916
00:48:43,400 --> 00:48:46,120
Speaker 1: Well it's it's yeah, I mean, if they discussed in

917
00:48:46,160 --> 00:48:48,279
Speaker 1: that of that talk, it's like you you, first of all,

918
00:48:48,320 --> 00:48:51,200
Speaker 1: you might question, well, one of my results actually saying,

919
00:48:51,239 --> 00:48:53,520
Speaker 1: but then you may be reaching the point where you're

920
00:48:53,520 --> 00:48:57,799
Speaker 1: having to move beyond, uh, these theories and work with

921
00:48:57,880 --> 00:49:01,000
Speaker 1: new theories. So as we learn more about black holes,

922
00:49:01,040 --> 00:49:04,759
Speaker 1: we're not just learning more about this arguably kind of

923
00:49:04,800 --> 00:49:08,120
Speaker 1: abstract seeming thing that has no direct influence over our

924
00:49:08,160 --> 00:49:10,080
Speaker 1: lives here on Earth. But it changed. But they have

925
00:49:10,120 --> 00:49:12,960
Speaker 1: the ability to change our understanding of the cosmos itself.

926
00:49:13,000 --> 00:49:15,680
Speaker 1: I mean, wouldn't it be a fascinating thing if we

927
00:49:15,680 --> 00:49:19,800
Speaker 1: were alive to see a new better theory of gravity emerge?

928
00:49:20,520 --> 00:49:23,160
Speaker 1: It would? It would? It would it would change everything.

929
00:49:23,200 --> 00:49:25,239
Speaker 1: It's like it's like them. It's it's kind of like

930
00:49:25,280 --> 00:49:28,680
Speaker 1: when they made another Blade Runner movie, except except even

931
00:49:28,760 --> 00:49:31,839
Speaker 1: more ground shaking. You know, like you grow up thinking

932
00:49:31,840 --> 00:49:33,520
Speaker 1: you're only going to ever have that one, and then

933
00:49:33,560 --> 00:49:36,040
Speaker 1: they go and make another one, and then likewise you

934
00:49:36,280 --> 00:49:38,239
Speaker 1: we would be living in a in a world in

935
00:49:38,280 --> 00:49:42,719
Speaker 1: which we had our third gravitational theory, So third major one. Yeah,

936
00:49:42,840 --> 00:49:46,520
Speaker 1: that would be really cool. Yeah. So yeah, astrophysicists, please

937
00:49:46,560 --> 00:49:50,600
Speaker 1: go out there and break Einstein kick his butt. Alright, Well,

938
00:49:50,600 --> 00:49:53,920
Speaker 1: on that note, we're going to uh, we're going to

939
00:49:54,040 --> 00:49:56,319
Speaker 1: rock it away from the event horizon. Now, we are

940
00:49:56,400 --> 00:49:59,799
Speaker 1: going to close this episode out. As always, we urge

941
00:49:59,800 --> 00:50:01,520
Speaker 1: you to check out Stuff to Blow your Mind dot com.

942
00:50:01,520 --> 00:50:04,600
Speaker 1: That's the mothership. That's what we'll find all the podcast episodes.

943
00:50:04,920 --> 00:50:07,640
Speaker 1: You'll find videos and blog posts there as well, also

944
00:50:07,719 --> 00:50:10,160
Speaker 1: links out to our various social media accounts. Oh it's

945
00:50:10,160 --> 00:50:11,600
Speaker 1: stuff to Blow your Mind dot com. And if you

946
00:50:11,600 --> 00:50:14,320
Speaker 1: want us to help support the show, go to wherever

947
00:50:14,360 --> 00:50:17,839
Speaker 1: you obtain the podcast uh and rate and review us.

948
00:50:18,000 --> 00:50:20,120
Speaker 1: Leave us a nice review, give us all the stars

949
00:50:20,120 --> 00:50:23,720
Speaker 1: you can, and that will help support the show huge.

950
00:50:23,760 --> 00:50:26,960
Speaker 1: Thanks as always to our excellent audio producers. Alex Williams

951
00:50:26,960 --> 00:50:28,880
Speaker 1: and Tarry Harrison. If you would like to get in

952
00:50:28,960 --> 00:50:30,839
Speaker 1: touch with us to let us know feedback on this

953
00:50:30,880 --> 00:50:34,239
Speaker 1: episode or any other, or to say where you listen

954
00:50:34,280 --> 00:50:36,400
Speaker 1: to the show from, or to suggest a topic for

955
00:50:36,400 --> 00:50:38,600
Speaker 1: a future episode, whatever it is, you can get in

956
00:50:38,640 --> 00:50:41,800
Speaker 1: touch with us directly by email at blow the Mind

957
00:50:41,840 --> 00:50:53,320
Speaker 1: at how stuff works dot com. For more on this

958
00:50:53,480 --> 00:50:56,000
Speaker 1: and thousands of other topics, is it how stuff works

959
00:50:56,000 --> 00:51:12,760
Speaker 1: dot com. The four ft spart