Time Travel at the Movies

Travel back to the future for a discussion of time travel and the movies that depict such excellent adventures.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Neil deGrasse Tyson?

  Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. I'm your host, Neil deGrasse Tyson, your personal astrophysicist, and I also serve as director of New York City's Hayden Planetarium. Today is the second hour of our sci-fi movie show, and I'm joined by my comedian co-host, LeAnn Lord. I'm also happy to welcome back the bad astronomer, Phil Plait. The topic today is time travel. So, let's just talk about time travel in the world of science. So, what can you bring to the table?

• 0:46Speaker 01

  Well, it depends on what you mean by time travel. I mean, traveling into the future is...

• 0:49Neil deGrasse Tyson?

  What do you mean, "it depends"? What do you mean?

• 0:51Speaker 01

  Well...

• 0:52Neil deGrasse Tyson?

  Which word did you not understand in that sentence?

• 0:55Speaker 01

  Well, there's a positive and negative, right? We all travel in time. We're going forward, you know, a minute every 60 seconds. So, we're going into the future, like it or not. You're gonna see it. But you can travel...

• 1:06Neil deGrasse Tyson?

  But we're trapped in the present as we move to the future.

• 1:08Speaker 01

  Yeah, but when you said that, it was the present, but now it's the past. Ooh, spooky.

• 1:14Speaker 02

  You guys really shouldn't do Hallmark cards. I'm just saying.

• 1:18Speaker 01

  Well, but we're traveling into the future, and if you wanted to see what it's gonna be like 100 years from now, there are ways to do that. And if you want to see what things were like 100 years in the past, there are kinda ways to do that, but if you want to see what the Earth was like 100 years ago, we can talk about that, too.

• 1:38Neil deGrasse Tyson?

  So, let's do it.

• 1:39Speaker 01

  All right. Well, traveling into the future, if you want to see the distant future, there are ways to do it. Suspended animation, for example, would work if there were some feasible way of doing it biologically. We don't know how to do that.

• 1:49Neil deGrasse Tyson?

  So, we just slow down your bio-functions so that you basically age more slowly. This is a common way in sci-fi movies decades ago where they go on long trips and they put you in some kind of suspended animation.

• 2:04Speaker 01

  Right, it takes, you know, a hundred years to get from here to there. So you freeze the, the people and, and they can wake up when they get to their destination. We don't know how to do that. You freeze somebody, they're, they're frozen.

• 2:15Neil deGrasse Tyson?

  I'm told Walt Disney knows how to do it.

• 2:17Speaker 01

  Yeah, if we, I suppose we could send his head to Alpha Centauri and see what happens.

• 2:20Speaker 02

  Bad freezer burn, fellas.

• 2:22Speaker 01

  Yeah, that's true. Uh, yeah, you've got something on your nose. Oh, sorry, frostbite over your entire brain. All right. Um, but that, that is, you know, possibly one way. Another way would be to travel very quickly. And according to Einstein's, you know, yeah, relativity. Uh, if somebody who's moving very rapidly relative to someone on Earth would age more slowly. And so if you were to get in a spaceship and move very close to the speed of light, you could literally travel across the galaxy and somebody on Earth would experience a hundred thousand years elapsing, while you might only experience, experience a few months elapsing. And that is time travel into the future because if you went to the star, you poked around, planted your flag, turnaround, came back, two hundred thousand years would have elapsed on Earth and, and you would have only experienced a short.

• 3:04Neil deGrasse Tyson?

  A couple of months for you.

• 3:05Speaker 01

  A fraction of that.

• 3:06Neil deGrasse Tyson?

  But by then, everyone would have forgotten about you.

• 3:08Speaker 01

  Well, basically, everybody's dead. So, yeah.

• 3:11Speaker 02

  So no child support.

• 3:13Speaker 01

  Ooh, yeah. Um, and yeah, no taxes. Hey, there may be some advantages to this. Uh, but the problem with that is we have no clue how to go that fast.

• 3:20Neil deGrasse Tyson?

  No, I bet everyone who wants to travel to the future wants to be able to come back to the present.

• 3:24Speaker 01

  Yeah.

• 3:24Neil deGrasse Tyson?

  That's my sense of it.

• 3:25Speaker 01

  So really, yeah, the honest definition of time travel is being able to travel backwards in time. And, you know, I'm not.

• 3:32Neil deGrasse Tyson?

  Or, or just treat the timeline as, as an accessible dimension, like a road.

• 3:40Speaker 01

  You can get off and get back on some other place or go back to where you were as many times as you want. Cloverleaf.

• 3:45Neil deGrasse Tyson?

  Okay.

• 3:46Speaker 01

  A chronic, a chronological cloverleaf.

• 3:48Neil deGrasse Tyson?

  Mm-hmm.

• 3:49Speaker 01

  Um, write that down. I'm gonna patent that and make that into a URL. I don't know how I feel about that. Traveling backwards in time. You know, the, the thing is, if you go back in time, the, the, the usual paradox is, I'd make a time machine, I'd go back in time, I'd kill my grandfather before he meets my grandmother, and I'm never born. And I, you know, and I always wonder about that.

• 4:08Neil deGrasse Tyson?

  And then if you're never born, you couldn't have gone back in time to prevent them from meeting each other.

• 4:11Speaker 01

  Exactly, it's a paradox. So, it's impossible to happen. I always wonder about that. Why do they always say grandfather? Why don't I just go back in time and kill my father? And I, I liked my father, I wouldn't have any desire to do this, but...

• 4:21Neil deGrasse Tyson?

  That's why they don't portray that in film.

• 4:23Speaker 01

  Yeah, maybe, maybe.

• 4:24Neil deGrasse Tyson?

  Because it's a little more diabolical to kill your parents than...

• 4:26Speaker 01

  Oedipus time wrecks, I don't know.

• 4:28Neil deGrasse Tyson?

  Plus, plus, why even kill them? All you have to do is prevent them from meeting.

• 4:31Speaker 01

  That's right.

• 4:32Neil deGrasse Tyson?

  That's all.

• 4:33Speaker 01

  If you, if they don't meet at the Enchantment Under the Sea prom dance, right, then they'll never meet.

• 4:37Neil deGrasse Tyson?

  Put them on different trains, then they don't meet.

• 4:39Speaker 01

  Exactly, and so, uh, there are...

• 4:40Neil deGrasse Tyson?

  Give one of them bad breath before they encounter, you know?

• 4:43Speaker 01

  And, and there, there are other paradoxes involved. That's, that's sort of the canonical one, the one that everybody always brings up. Um, there are, there are other ones, I mean, what happens to the atoms that you're made of in the future and you bring them back into the past, they're the same atoms existing in two different places at the same time, and that doesn't make sense.

• 4:58Neil deGrasse Tyson?

  Oh, because presumably your presence still exists in the present.

• 5:00Speaker 01

  Yes. So, if, if everybody in the future went back in time, suddenly, there's more people, there's more mass in the universe than there was.

• 5:07Neil deGrasse Tyson?

  At that time.

• 5:08Speaker 01

  Yeah, at that time, and so that can't, maybe averaged over the age of the universe, it's all the same.

• 5:12Neil deGrasse Tyson?

  You know, it's been said that, in the future, they have actually invented a time machine, and the most curious historical event that has piqued people's interest is the sinking of the Titanic.

• 5:20Speaker 01

  Yes.

• 5:21Neil deGrasse Tyson?

  So, they all went back to the Titanic, to see it sink, and that's why it sank, because everybody overloaded the Titanic.

• 5:26Speaker 01

  This was my, this was my idea for a short story, in fact. The reason the Titanic sank is because nobody knew how to steer the ship, because they were all time travelers from the future. It's like they're all standing there like, "Oh, there's a, there's an iceberg, we should do something." And they're like, "I don't know how to do something, all I know is I can pilot a rocket ship, but I don't know how to do a cruise liner and sink."

• 5:40Neil deGrasse Tyson?

  Right, and, and, yeah, steamship cruise liner, yeah.

• 5:42Speaker 01

  And I, and I, yeah, I always liked that idea.

• 5:44Neil deGrasse Tyson?

  So, maybe, actual events that we, that have happened in the past, have already been influenced by time travelers, what do you think of that?

• 5:51Speaker 01

  Right, and so, the other idea is that if you travel backwards in the past, the, the time is fixed, and it's, it's, it's not like a river flowing, it's more like a landscape, and you can move from one place to the other, but it's fixed. If you, if you go back in time and do something, then that, that happened always. So, you can't go back and kill your grandfather, all you can do is, uh, whatever random things you're doing, but no matter what you do, your grandfather and grandmother are going to meet, they're going to have one of your parents, and they're going to have you, you cannot change the past.

• 6:21Speaker 02

  So, you're saying there's no way I'm going to change my SAT score?

• 6:24Speaker 01

  That's right. If you go back in time to change your SAT score, whatever you do will ensure that you got the SAT score you did when you were a kid.

• 6:30Neil deGrasse Tyson?

  Right, so this is...

• 6:31Speaker 02

  21, you can watch!

• 6:37Speaker 01

  I love thinking about this because it's like, it sounds so confusing, but when you think about it, it makes perfect sense. No matter what you do, what's gonna happen is what's gonna happen.

• 6:44Neil deGrasse Tyson?

  Okay, but that's a hypothesis. What I'm asking you for now is, what science do you know that allows backward time travel? And I don't really know of any.

• 6:53Speaker 01

  I don't, I've heard some theoretical things and some really crazy physics involving infinitely long cylinders that are rotating near the speed of light and all kinds of crazy stuff like that.

• 7:02Neil deGrasse Tyson?

  And you take a loop around it that where you revisit your world line earlier than when you left?

• 7:07Speaker 01

  Yeah, it's like doubling back on your own timeline.

• 7:10Neil deGrasse Tyson?

  Right.

• 7:10Speaker 01

  And I don't, I'll be honest, I don't understand that kind of physics. That's way over my head. Or possibly going around a black hole and there are ways of going through it and coming back at a different point in space and time. Space and time are related and in a black hole, they kind of sort of swap places.

• 7:24Neil deGrasse Tyson?

  And in a few months, we'll have lost all capacity to go back into orbit the Earth. So conversations about orbiting black holes is not only science fiction, it's like something completely out of reach.

• 7:34Speaker 01

  It seems a little farfetched right now.

• 7:36Neil deGrasse Tyson?

  Alright, so what you're suggesting is even though there's no real accessible way to go backwards in time, it doesn't prevent anyone from thinking about the consequences of it.

• 7:45Speaker 01

  Sure thing. And I like thinking about it. It's a fun mental exercise.

• 7:47Neil deGrasse Tyson?

  A fun mental exercise. And of course, many films have addressed this, which we'll get to later in this hour. But until then, let's talk about going into the future. Einstein, with his relativity, demonstrates that this is possible. People freaked out. They said, no, you can't travel into the future. I mean, so relativity had some naysayers at the time. This, we're now talking 100 years ago, 1905, right?

• 8:10Speaker 01

  Well, time keeps on slipping, slipping, slipping into the future, I believe.

• 8:15Speaker 02

  So fly like an eagle.

• 8:17Speaker 01

  Oh, is that what that is? Oh, I'm sorry. I thought that was thorough.

• 8:23Speaker 01

  Yeah, and sure, even when Einstein came out with his ideas, people were having a problem with it. But come on, it's weird. That time is fluid, like you can, you all know that, you know, waiting for a watch pot never boils, and if you're bored, time seems to take longer, but that's just perception. Einstein was talking about a physical change in the way time elapses, and if you're, if you're moving very quickly, your time slows down relative, that's where the relativity word comes from, someone who's not moving, or if you're in a deep gravity field, your time seems to move slower than somebody outside.

• 8:58Neil deGrasse Tyson?

  So an important distinction there is, I think earlier on, people were saying, well, if it's just my perception that time has slowed down, then a watch shouldn't know the difference if it's just my biology, and, but in fact, it's everything, it is the fabric of space and time that is providing this, this, this ability, or this feature.

• 9:15Speaker 01

  That's right, and when I talk to people about this, and I'm sure as you do as well, when you do your, your public outreach, you really have to say, no, it's not just that you think time is slowing down, your watch is physically ticking at a different rate than a different one.

• 9:27Neil deGrasse Tyson?

  And so too is your metabolism, the rate your atoms vibrate.

• 9:30Speaker 01

  Everything, yes, subatomic particles are decaying and doing whatever it is they do on a daily basis, when, you know, behind closed doors, they're, they're doing that at a different rate. It's their business. It really is, but you know, it can speed up or slow down, and so, you know, there's probably some purry and interest in this, but, but in general, you know, that, that, their time is different.

• 9:47Neil deGrasse Tyson?

  Now, over, over, and earlier before the show, you were talking about GPS and how that needs relativistic corrections, tell us about that.

• 9:56Speaker 01

  This is something I like, I, I, you must get email, I get email, oddly enough, when you, when you, when you go out there and, and try to talk about science and correct people's misunderstandings of science, you get email from people who are, I have this theory, and I, I constantly get people. I'm sorry, I'm very sorry, I have questions. Okay, yes, please, stop emailing me, Leanne. Oh my god. Um, I'll get people saying, I have a theory that overthrows relativity, and it's like, no, no you don't, okay, you don't, and relativity is one of the best tested ideas of all time, and in fact, the, the, the one thing I tell people is, you, everybody uses a GPS these days.

• 10:32Neil deGrasse Tyson?

  In some way or another.

• 10:33Speaker 01

  It's in your phone, it's in your car, whatever, and GPS has to account for relativity. The satellites that are orbiting the earth that are used for Global positioning are actually high enough up that the gravity they feel from the earth is actually a little bit different than the gravity we feel here at the surface. And that makes their clocks tick a little bit faster than ours.

• 10:53Neil deGrasse Tyson?

  As specified by relativity.

• 10:54Speaker 01

  Yes, and relativity says bam, this is what it is.

• 10:58Neil deGrasse Tyson?

  So, relativity says if you're deep in a gravity well, as we are down on the surface of the earth.

• 11:03Speaker 01

  That's right.

• 11:04Neil deGrasse Tyson?

  Gravity will tick more slowly than if you're at a lesser gravity high up.

• 11:06Speaker 01

  That's right.

• 11:07Neil deGrasse Tyson?

  And so, these are orbiting high up, so their clocks are ticking at a different rate, yet they're trying to tell you what time it is.

• 11:12Speaker 01

  Oh, but wait a moment, Neil, because it gets worse than it.

• 11:15Neil deGrasse Tyson?

  But wait, there's more.

• 11:16Speaker 01

  Wait a moment, this moment will stretch out relativistically. In fact, Einstein also said that if you're moving relative to somebody else at a high velocity, your clocks will slow down. And these satellites are orbiting the earth at fifteen, eighteen thousand, whatever it is.

• 11:29Neil deGrasse Tyson?

  Fifteen thousand miles an hour, yeah.

• 11:30Speaker 01

  They're moving very quickly.

• 11:31Neil deGrasse Tyson?

  So, they've got two strikes against them.

• 11:32Speaker 01

  So, their clocks are faster than ours a little bit because they're experiencing lower gravity, but they're moving so rapidly, their clocks are actually moving slower than ours. When you take these two effects into account.

• 11:43Neil deGrasse Tyson?

  What's the net effect?

• 11:44Speaker 01

  The net effect is that their clocks are ticking more slowly. You have to account for both of these to get it right. And since global positioning satellites have to know where their position is and where your position is to figure out of the position, the P in GPS, if you don't account for relativity, and they use clocks to do this.

• 12:00Neil deGrasse Tyson?

  I like that the P in GPS, that's good.

• 12:02Speaker 01

  That's right, I mean, it doesn't stand for Phil or plate, it's actually position. If you don't account for these relativistic effects, your GPS would be off by some large amount, hundreds of yards or a fraction of a mile, every single day.

• 12:15Neil deGrasse Tyson?

  And that would accumulate, presumably.

• 12:16Speaker 01

  Yes, it would. And so, the fact that your GPS can nail you down to a few yards wherever you're standing means that relativity is correct.

• 12:24Neil deGrasse Tyson?

  So, the people that say relativity is wrong, they just have no, yet they're happy to use their GPS.

• 12:30Speaker 01

  Yes, and so, they're absolutely wrong. There's no relative here, they're wrong.

• 12:34Neil deGrasse Tyson?

  They're wrong, not, right, so.

• 12:37Speaker 01

  Turn right ahead.

• 12:40Neil deGrasse Tyson?

  Relatively not only works on paper, it works in space.

• 12:43Speaker 01

  Yes, and there are other things too. We see subatomic particles with very short lifetimes that are created at the top of the atmosphere when cosmic rays hit our air. And these subatomic particles we detect on the ground could not possibly reach the ground in the amount of time. So we know that they're moving so quickly that their clocks have slowed down and they have the lifetime to make it.

• 13:00Neil deGrasse Tyson?

  So it affects, obviously, not only wristwatches and biological metabolism, it's affecting the rate at which particles decay.

• 13:08Speaker 01

  The very fabric of the universe is relative.

• 13:10Neil deGrasse Tyson?

  They even know about the relativity.

• 13:12Speaker 01

  That's exactly right. That's deep.

• 13:13Neil deGrasse Tyson?

  That is sooo deep. When we come back, we're going to take a tour of all the best time travel movies there are and see how well they do. This is StarTalk Radio.

• 13:47Neil deGrasse Tyson?

  This is StarTalk Radio. Welcome back. So what did you think of Planet of the Apes?

• 13:51Speaker 01

  I love that movie. The original with Charlton Heston.

• 13:53Neil deGrasse Tyson?

  Yeah, and they had the...

• 13:54Speaker 01

  And Rodney McDowell.

• 13:54Neil deGrasse Tyson?

  They had people suspended in suspended animation, as we discussed in the first segment.

• 13:58Speaker 01

  Right.

• 13:59Neil deGrasse Tyson?

  Because they didn't know how long. You don't want to use up your resources. And then some of them died, I think, when they landed. Is that right?

• 14:06Speaker 01

  There was a woman on board who dies in suspended animation. One of his fellow astronauts gets shot, and then another one gets shot and stuffed and put into a museum.

• 14:15Neil deGrasse Tyson?

  I remember that. And you see the cotton in his eyes.

• 14:17Speaker 01

  Yikes. Yeah, that was so grim.

• 14:19Neil deGrasse Tyson?

  Well, that's what...

• 14:20Speaker 01

  Damn.

• 14:21Neil deGrasse Tyson?

  Because they're the damn dirty apes.

• 14:22Speaker 01

  Yeah.

• 14:23Neil deGrasse Tyson?

  So tell me about the time travel in that. Comment on its accuracy. What do you think?

• 14:27Speaker 01

  It was fine. They're traveling to a different star, so they're moving very rapidly.

• 14:32Neil deGrasse Tyson?

  So they must have gone in some loop because they landed back on Earth but didn't know it.

• 14:36Speaker 01

  Yeah, so they must have gone in a circle.

• 14:38Neil deGrasse Tyson?

  Let's make this clear. This is not some parallel planet that had a different evolutionary track. This is Earth that he comes back to in the future.

• 14:45Speaker 01

  Right.

• 14:45Neil deGrasse Tyson?

  And what, humans evolved back into apes? Is that...

• 14:49Speaker 01

  Well, yeah.

• 14:50Neil deGrasse Tyson?

  Leanne, does your data support this, that humans are evolving back to apes?

• 14:54Speaker 02

  Uh, I'm actually-

• 14:55Neil deGrasse Tyson?

  Back to hairy apes, I think.

• 14:56Speaker 02

  I'm actually not convinced of what you just said. How do we know it's not an alternate developmental track? How do we know that?

• 15:02Neil deGrasse Tyson?

  Oh, yeah, yeah.

• 15:03Speaker 01

  Well, in the-

• 15:03Neil deGrasse Tyson?

  Phil, yeah.

• 15:04Speaker 01

  There are some, there are some lines in the movie-

• 15:05Neil deGrasse Tyson?

  Mr. Movie Critic?

• 15:06Speaker 01

  So, we know it's the Earth in the end because he's at the Statue of Liberty. And, and so there's some other things that indicate it's Earth. Um, there's some, there's some gotcha lines in it when they're, they're on a raft and they're going down the river and they're trying to figure out where they are. One of them looks up at the, at the sun in the sky and says, "It's a little too yellow. Do you think it's Bellatrix?" Which is a real star in Orion. And, and they're sort of misleading you, making you think they're on a different planet. Uh, and in the sequels, in Beneath the Planet of the Apes, and Battle for the Planet of the Apes, and, uh, Apes and the, Apes of the Planet, I don't even, there was like five sequels. Uh, they actually establish how, uh, there's, one of the apes comes back in time. And that's where you have to assume there's time travel. The ape goes back in time and becomes the first ape that can talk, and then leads the revolution,

• 15:50Speaker 01

  which becomes the Planet of the Earth.

• 15:52Neil deGrasse Tyson?

  Oh, so what you're saying is that the entire premise of that movie required backwards time travel?

• 15:59Speaker 01

  I don't think in the first movie it does.

• 16:01Neil deGrasse Tyson?

  That they'd thought that through?

• 16:02Speaker 01

  I, I don't think so. And in the original book, uh, it's actually-

• 16:05Neil deGrasse Tyson?

  Well, you read the books too.

• 16:06Speaker 01

  Yeah, it's actually, it's actually a decent book.

• 16:08Speaker 02

  He's a Renaissance man.

• 16:09Speaker 01

  It really, yes, I still read. Um, but then this was like 20 years ago when I still read. Now I prefer to just, you know, sleep. But, uh, I believe they go to another planet, and it's a parallel evolution. And they come back to Earth. And the big twist is apes have taken over during the time they were gone.

• 16:24Neil deGrasse Tyson?

  Right, right.

• 16:25Speaker 01

  Uh, maybe not as much impactful as, you know, pounding the sand and, and screaming at the Statue of Liberty, but still, it's a decent book.

• 16:32Neil deGrasse Tyson?

  Okay. And so, now how about Groundhog Day? That's a fun one. That's, that's the time travel I think we all wish we could be part of, because you get to slightly change what happens.

• 16:43Speaker 01

  Speak for yourself.

• 16:44Neil deGrasse Tyson?

  To ch- you get to change the past. He wakes up every morning, relives the day, but he has a memory of what happened the last time. What do you think of that?

• 16:55Speaker 01

  It's an interesting premise. It's never really explained. Uh, it's clearly not the groundhog itself, because he kills the groundhog, uh, in a, what, he steals a truck and- Dives over the edge of a quarry and he still wakes up, uh, listening to Sonny and Cher. And, and you know, if you want to wake up, I've got you babe.

• 17:09Neil deGrasse Tyson?

  You remember this much about the movie.

• 17:11Speaker 01

  Oh, yeah, yeah.

• 17:12Neil deGrasse Tyson?

  This is scary, Phil.

• 17:13Speaker 01

  It's a good flick.

• 17:14Neil deGrasse Tyson?

  Phil, this is scary.

• 17:14Speaker 01

  Well, you know, it's, it's, his name is Phil in the movie. Uh, and so.

• 17:17Neil deGrasse Tyson?

  The groundhog or him?

• 17:18Speaker 01

  The groundhog, both. And so everybody teases him about that.

• 17:21Neil deGrasse Tyson?

  I thought Phil was his last name. Punxsutawney.

• 17:24Speaker 01

  Punxsutawney Phil.

• 17:25Neil deGrasse Tyson?

  Yeah, yeah, okay.

• 17:26Speaker 01

  But, but his name is Phil. Okay, okay, we need to, to, to.

• 17:29Speaker 02

  Okay, now's when the experts tweeting.

• 17:31Speaker 01

  Oh, yeah, Google it, it doesn't matter.

• 17:32Neil deGrasse Tyson?

  We got our engineers tweeting there.

• 17:33Speaker 01

  But, uh.

• 17:34Neil deGrasse Tyson?

  I mean, uh, uh, Googling, yes.

• 17:35Speaker 01

  It was kind of a cool idea and you don't really ever find out how long he was in there. But he was in there long enough to be able to become a, you know, an incredible piano player at the end of the, end of the movie. And I think there was an interview, was it Rob, was it Robert Zemeckis or John Landis who directed this movie? Well, whoever. There was an interview with him saying he was actually trapped in there for years, maybe even hundreds of years.

• 17:56Neil deGrasse Tyson?

  Long enough to be able to heck, uh, acquire that expertise.

• 17:59Speaker 01

  Yeah.

• 17:59Neil deGrasse Tyson?

  Okay.

• 18:00Speaker 01

  And, and to me, that would be the ultimate torture to be able to, to be trapped in a, in one place like that and have to live that over and over again. It would make me crazy.

• 18:06Neil deGrasse Tyson?

  How about Superman?

• 18:07Speaker 01

  Uh.

• 18:08Neil deGrasse Tyson?

  Original Superman, the movie.

• 18:09Speaker 01

  Okay.

• 18:10Neil deGrasse Tyson?

  The one where you will believe man can fly.

• 18:12Speaker 01

  Yeah, Christopher Reeve is, I, okay, I love this movie. I, nineteen seventy, whatever. It's still one of John Williams' best soundtracks. I just think it's the, it's one of the best superhero movies. It takes it, it, it just takes itself exactly the right amount of seriously.

• 18:25Neil deGrasse Tyson?

  Wait, Superman two was a little better, but we're referring specifically to the time.

• 18:29Speaker 01

  The time travel.

• 18:29Neil deGrasse Tyson?

  The time reversal.

• 18:30Speaker 01

  I just want to get that out there, that I like this movie. Um, he, he flies around the earth and somehow.

• 18:36Neil deGrasse Tyson?

  Backwards.

• 18:37Speaker 01

  The earth spins the other way.

• 18:38Neil deGrasse Tyson?

  He flies around the earth backwards from the rotation.

• 18:40Speaker 01

  And I think there was a little bit of confusion there. I think that he was supposed to be traveling so close to the speed of light that he was reversing time.

• 18:46Neil deGrasse Tyson?

  Mm-hmm.

• 18:46Speaker 01

  But it looks like he's flying around the earth so quickly that the earth somehow gets dragged backwards and spins backwards. As if you're just spinning the earth backwards would spin backwards time.

• 18:55Neil deGrasse Tyson?

  Leaving everyone to think, yeah, if, that if you just turn the earth backwards, that time would reverse.

• 18:58Speaker 01

  Yeah, and why doesn't he reverse time a couple of days? So he has more time to fix things. And let me tell you something, the whole reason this thing happens is because Lex Luthor is shooting two missiles in opposite directions.

• 19:08Neil deGrasse Tyson?

  Right.

• 19:09Speaker 01

  And he promises Miss Testmacher, and yes, believe me, I know this movie, that he's going to stop the missile heading towards New Jersey.

• 19:15Neil deGrasse Tyson?

  Hackensack, where her mother lives.

• 19:16Speaker 01

  Hackensack, New Jersey, because where her mother lives, that's exactly right. And so he has to stop that when he can't stop the one that hits the San Andreas Fault. That's why Lois Lane gets killed and he has to make the earth go backwards. He can't catch up to a missile. But he can fly around the earth fast enough to make it spin backwards. Hello?

• 19:30Neil deGrasse Tyson?

  Yeah, that's crazy. That's crazy. Plus, at the time, I had a girlfriend and we saw the movie together and he starts flying backwards and reverses time. And she turns to me and says, "Can he really do that?" And I said, "Why didn't you ask me earlier whether a man in blue pantyhose can fly?"

• 19:44Speaker 01

  Right.

• 19:44Neil deGrasse Tyson?

  Why is this the first issue that you have with the physics of the film?

• 19:47Speaker 02

  People have different thresholds.

• 19:48Speaker 01

  And, and if you ever watch a Big Bang Theory on TV and the first episode, they go through this.

• 19:52Neil deGrasse Tyson?

  I did not see the first episode. I have to go back to my, the archives.

• 19:55Speaker 01

  They're talking to somebody about this and saying, you know, can Superman fly or does he just jump?

• 20:00Neil deGrasse Tyson?

  Hmm.

• 20:00Speaker 01

  And, and, and it, it, there's this whole thing about, she says, "Oh, well, people can't really fly." And, and, and one of the nerds actually says, "Oh, no, let's assume that." It's like, the first thing that a science nerd would actually say, "No, blah, blah, blah." And so they actually, they just sweep right past that. I love that scene. It's very funny.

• 20:16Neil deGrasse Tyson?

  Okay, so that's, so you're saying, obviously, he can't do that, but he's Superman, so they, why not let him do it? In the, it's Superman physics. It's not real physics.

• 20:25Speaker 01

  Yeah, you know, he can fly. He's invulnerable.

• 20:27Speaker 02

  Superman physics. Is there a degree in this?

• 20:29Speaker 01

  Is, is that, is that what makes it so that when he puts on a pair of glasses, nobody knows that he's Superman?

• 20:34Neil deGrasse Tyson?

  Yeah, that's, well, yeah, that's how they, that's, that's, you know. Yeah. So, how about, how about Star Trek IV, The Voyage Home?

• 20:40Speaker 01

  Voyage Home with the whales.

• 20:41Neil deGrasse Tyson?

  That's had some star, time travel back to our present of the day. It was Save the Whales. That was the subtitle for that one.

• 20:49Speaker 01

  And Star Trek did this in the series a few times. And they've, they've, they've done this in the movies. You know, it, it's, in the series, they established that if you, if you warp around the sun, it'll somehow make you go back in time. And since that's moving, since moving faster than light, as far as we know, is impossible anyway, and who knows how this physics works? Sure, yes, warping around the sun can make you go back in time.

• 21:10Neil deGrasse Tyson?

  Wait a minute, but if, but we all know that tachyons, which exist faster than light, do move backwards in time.

• 21:17Speaker 01

  Well, we don't know if they're real, though.

• 21:18Neil deGrasse Tyson?

  But, but if they did exist, they would move backwards in time.

• 21:21Speaker 01

  Because they're moving faster than light.

• 21:24Speaker 02

  And if Neil is making sense.

• 21:26Neil deGrasse Tyson?

  No, no, but they're good ifs. These ifs are better than other ifs.

• 21:30Speaker 02

  Alrighty.

• 21:30Neil deGrasse Tyson?

  So, so.

• 21:31Speaker 01

  I have some buts for your ifs.

• 21:34Speaker 02

  And then some then's.

• 21:35Neil deGrasse Tyson?

  So, so the point is, in Einstein's equations, if you put in faster than light velocity, you get backwards time travel. So you hypothesize a particle that would do this. So, if you, or in a sci-fi story, and you go faster than light, as they're doing all the time with their warp drives, they can, in principle, go backwards in time, like the tachyons can.

• 21:57Speaker 01

  I will have to grant that. I never took a class in general relativity in grad school, so actually, I don't know. So, you could be making this up, and I would, sure. Yes, Neil, of course. I think it's patently obvious, even the most dim-witted observer, that of course, you're correct.

• 22:13Speaker 02

  Doesn't this only work if Scotty is your engineer?

• 22:15Speaker 01

  Yes.

• 22:16Speaker 02

  Okay.

• 22:16Neil deGrasse Tyson?

  And only if occasionally the engines can't take it. Right, yes.

• 22:19Speaker 01

  That's right.

• 22:20Neil deGrasse Tyson?

  So, what did you think of the scene where he helps the engineer on his Mac Plus, whatever the computer was at the time? He helps the engineer invent transparent aluminum. And then they worry that he affected time in the past, which of course, the very existence back then is doing this, alright? They're affecting events. And then he said, well, how do you know he's not the guy who invented it?

• 22:46Speaker 01

  Right, and then McCoy leans over and says that to Scotty, and he's like, oh. So, so, yeah, I mean, if you're gonna explain a big time travel paradox, that's a great way to do it, shuffle it right under the rug. I thought that was hysterical. And here's Scotty, who's picking up a mouse, because he doesn't know that it's not a...

• 23:00Neil deGrasse Tyson?

  The computer mouse, yeah.

• 23:01Speaker 01

  Yeah, a microphone to talk to it. And yet, he can seem to program in the Mac OS operating system, you know, from 1980, whatever it was.

• 23:09Speaker 02

  But that's an ad about how simple it is. It wasn't Windows.

• 23:11Neil deGrasse Tyson?

  Oh, there it is.

• 23:12Speaker 01

  It just works, yeah.

• 23:14Neil deGrasse Tyson?

  So, another, one of my favorite piece of that film was when McCoy, the doctor, McCoy, is walking through the hospital, just healing everybody.

• 23:22Speaker 01

  Yeah, that's right.

• 23:22Neil deGrasse Tyson?

  Yeah.

• 23:23Speaker 01

  Doctor gave me a pill, and I grew a new kidney.

• 23:26Neil deGrasse Tyson?

  A new kidney. And I'm thinking, you know, maybe that's kinda cool. We do some of that today, compared with medicine from 200 years ago. It looks like, would look like magic today.

• 23:36Speaker 01

  I have to wonder what medicine is gonna be like. And, and I would assume a lot of it is gonna be just even cutting around a lot of the problems we have today. They'll... Won't even have to worry about stuff like that.

• 23:46Neil deGrasse Tyson?

  So we all look forward to medicine of the future, for sure. One of my favorite of the benchmark movies was Time Machine itself, H.G. Wells. Done a few times in film. What I found interesting, most interesting about it was, his loved one died. And his love interest died, the main character's love interest, and he went back to keep trying to save her, and everything he tried to do to save her would get her killed. And so he recognized that that was a fundamental part of the timeline that he could not change.

• 24:13Speaker 01

  Oh, so this is in the remake, the recent remake?

• 24:15Neil deGrasse Tyson?

  The remake, yes, yes, that was captured.

• 24:17Speaker 01

  Although, honestly, he went back once and tried and it didn't work, and then he's like, oh, oh, well, that's it. Really? You can't show at least one other effort?

• 24:24Neil deGrasse Tyson?

  When we come back, we're going to talk about The Terminator. We'll see you after the break.

• 24:51Neil deGrasse Tyson?

  We're back on StarTalk Radio with Phil Plait, the bad astronomer, and comedian LeAnn Lord. We're talking about time-traveling movies. And just before the break, we mentioned The Terminator, but I'm going to save that for a little later. Let's go into just a campy, fun movie, Bill and Ted's Excellent Adventure. How could you not love that movie?

• 25:12Speaker 01

  I really liked it. I thought it was quite funny.

• 25:14Neil deGrasse Tyson?

  I thought it was great. And, and any comments about the science of that?

• 25:18Speaker 01

  Well, in fact, if you take an umbrella...

• 25:22Neil deGrasse Tyson?

  That sentence actually came out of my mouth.

• 25:24Speaker 01

  If you take an umbrella and attach it to a telephone booth, and you happen to have George Carlin handy, time travel is in fact possible. I won't even mention, time-traveling phone booths may have been done by Doctor Who first, but...

• 25:37Neil deGrasse Tyson?

  And wasn't there a phone booth in Time Bandits, or not?

• 25:42Speaker 01

  Oh my gosh, I don't remember.

• 25:43Neil deGrasse Tyson?

  Yeah, I forgot that, maybe.

• 25:44Speaker 01

  Well, they had the map, but I don't remember.

• 25:46Speaker 02

  So is that why they've actually gotten rid of phone booths?

• 25:49Speaker 01

  Maybe, yeah.

• 25:50Neil deGrasse Tyson?

  People were moving around in time. And Superman uses it to become Superman. I mean, phone booths, where would we have been without them? They're storytelling.

• 25:57Speaker 02

  They're in Harry Potter as well.

• 25:58Speaker 01

  Man, they're the Swiss Army knife.

• 25:59Neil deGrasse Tyson?

  In Harry Potter.

• 25:59Speaker 02

  Yes.

• 26:00Speaker 01

  That's true. It's the Swiss Army knife of movie science.

• 26:02Speaker 02

  Bring it back.

• 26:03Neil deGrasse Tyson?

  So what I liked about Bill and Ted was that they kept the personalities of these characters in the present, and so Beethoven went into the music shop in the mall.

• 26:14Speaker 01

  Right.

• 26:15Neil deGrasse Tyson?

  And Genghis Khan's got the baseball bat, and Joan of Arc is conducting the aerobics lesson.

• 26:22Speaker 01

  Right.

• 26:23Neil deGrasse Tyson?

  I just thought that, it was kinda cool. It's what you'd want it to be if you could go back and bring historical figures into the present.

• 26:28Speaker 01

  There's a crucial scene when they need to get someplace and they need to get a car. I can't remember the exact details, but they're standing there talking, and they're saying, "We need to, you know, we have a time machine. We could go into the future, go into the past, get the keys to the car, and leave them for us here." Well, where would we leave them? How about right here behind the sign? And they walk behind the sign, and there are the keys.

• 26:46Neil deGrasse Tyson?

  That's right.

• 26:47Speaker 01

  It's like, I said, "We have to remember to do that later, dude."

• 26:49Neil deGrasse Tyson?

  Yeah.

• 26:50Speaker 01

  And they do, and it was like, I could not stop laughing in the theater watching.

• 26:53Neil deGrasse Tyson?

  So it was brilliant, actually.

• 26:54Speaker 01

  Yeah, yeah, it was actually a really, really well-done, tightly scripted movie.

• 26:58Neil deGrasse Tyson?

  They willed the keys to exist where they would look for them, but they had to remember to put them there when they went back in time.

• 27:05Speaker 01

  That's right, and I love that in movies, and to mention Doctor Who again as well, it's a British time travel show, when they actually use time travel that way, when they say, "I need to remember to go back in time and do this later." I just love stuff like that, it makes me giggle.

• 27:18Neil deGrasse Tyson?

  So, how about Terminator?

• 27:21Speaker 01

  Well, there you go.

• 27:22Neil deGrasse Tyson?

  That's a tight movie. I'll be back. That's a tight movie, you gotta admit.

• 27:29Speaker 01

  You know, that movie came out.

• 27:30Neil deGrasse Tyson?

  Wait, wait, first, geek off, geek off.

• 27:31Speaker 01

  Okay, okay.

• 27:32Neil deGrasse Tyson?

  Geek alert.

• 27:32Speaker 02

  Okay.

• 27:33Neil deGrasse Tyson?

  Can you recite every one of Arnold's lines in that movie? There are only five of them.

• 27:38Speaker 01

  Really?

• 27:38Neil deGrasse Tyson?

  Yes. Your clothes, give them to me. Good one, okay. Your clothes, give them to me, good.

• 27:43Speaker 01

  Blank, okay.

• 27:45Neil deGrasse Tyson?

  Sarah Connor?

• 27:47Speaker 01

  He says that a lot, yes.

• 27:49Neil deGrasse Tyson?

  Okay, you got another one?

• 27:51Speaker 01

  Blank off, blank hole. How about that? Or beep off, beep hole. Now, that sounds even worse. That's actually quite dirty, I think.

• 27:59Neil deGrasse Tyson?

  That's right, okay, so how about, um, uh, "What is your address there?"

• 28:03Speaker 01

  Give me your address there.

• 28:04Neil deGrasse Tyson?

  Give me your address there.

• 28:05Speaker 01

  Give me your address there.

• 28:06Neil deGrasse Tyson?

  Okay.

• 28:06Speaker 01

  Oh, gosh, what else is he to say?

• 28:11Speaker 01

  I don't remember.

• 28:11Neil deGrasse Tyson?

  I love the fact that he lands at Griffith Observatory and Planetarium in Los Angeles.

• 28:15Speaker 01

  Uh, yeah, that's right.

• 28:16Neil deGrasse Tyson?

  That's where he lands.

• 28:18Speaker 02

  Nice bit of product placement.

• 28:19Speaker 01

  Yeah, there you go. Um, your clothes can be used for... I can't remember anything else.

• 28:24Speaker 02

  So is Asta La Vista baby not in one?

• 28:25Neil deGrasse Tyson?

  No, no, no.

• 28:27Speaker 01

  Yeah, the young John Connor teaches him to say that.

• 28:29Speaker 02

  Yes, that's okay. Just testing you guys on your geek.

• 28:32Speaker 01

  And Al Bebok, when he leans over, I love that. And then the cops are sitting there doing his stuff and then the car crashes through.

• 28:38Neil deGrasse Tyson?

  So tell me about some of the... what might be the science of that?

• 28:42Speaker 01

  Well, you just have to kind of say, "Well, they invent time travel." Actually, the one beef...

• 28:49Neil deGrasse Tyson?

  Thank you, Phil, for coming from Colorado to New York to tell me this.

• 28:52Speaker 02

  Goodnight, everybody.

• 28:53Speaker 01

  Honestly, but that's... yeah, thank you and tip your waitress. Um, in fact, the thing that kills me is we've had this nuclear war, humans are on the run, we're about to be crushed, and yet somehow we have the wherewithal to invent time travel. Hey, maybe you should have built a bomb to blow up, you know, Skynet or something, but, you know. No, we'll work on time travel instead.

• 29:13Speaker 02

  Well, I thought... no, no, no. I thought the machines had worked on time travel and we just sort of stole that because they sent the Terminator back and then we sent Reese back to go after the Terminator.

• 29:22Speaker 01

  Is that clear? Because I... well, maybe because you said... they said the rebellion captures...

• 29:27Speaker 02

  Yeah.

• 29:27Neil deGrasse Tyson?

  So you're saying the machines invented the time machine?

• 29:29Speaker 02

  Yes, because their goal was to go back because John Connor was a pain in the butt. So they wanted to go back and kill...

• 29:34Neil deGrasse Tyson?

  To remove him from the equation.

• 29:35Speaker 02

  Exactly. So in order to save, you know, him, then they send Reese back.

• 29:40Speaker 01

  You're right, because Reese even says, "The machines were smashed. We had won." There's that line that Kyle Reese says.

• 29:46Speaker 02

  Did I just out geek?

• 29:47Neil deGrasse Tyson?

  Oh!

• 29:49Speaker 02

  Ho!

• 29:50Neil deGrasse Tyson?

  Lee and Lord.

• 29:51Speaker 02

  In the house.

• 29:52Neil deGrasse Tyson?

  Smackdown.

• 29:53Speaker 01

  Oh, man.

• 29:55Speaker 02

  Which you would not hear that sound in space.

• 29:57Speaker 01

  I feel... I feel terrible.

• 30:03Speaker 01

  Now we're going to invent time travel to go back in time and kill you before you say that. And then I can just say, "Oh, yes, the machines invented time travel." Didn't we have, didn't we have somebody else in the studio? What happened to her?

• 30:13Neil deGrasse Tyson?

  So there's something else they got right in the movie. There's the scene where Sarah Connor's actual twin double is shown in the film.

• 30:21Speaker 01

  That's in the second movie.

• 30:22Neil deGrasse Tyson?

  Oh, that's the second movie?

• 30:22Speaker 01

  Yeah, at the Iron Works, yeah, yeah.

• 30:24Neil deGrasse Tyson?

  Yeah, so she's there at the, at the playground, watching the children play. And a nuclear device goes off over, I guess that's Los Angeles, in the background.

• 30:32Speaker 01

  Oh, I know what you're gonna go with this, yeah.

• 30:33Neil deGrasse Tyson?

  And so, in a nuclear device, the energy that reaches you first is the light.

• 30:38Speaker 01

  Right.

• 30:39Neil deGrasse Tyson?

  From the explosion. Then, the shockwave reaches you, okay? So you get the light, and it is hugely intense, and it basically vaporizes you. Or whatever, it, it, it'll melt you, it'll vaporize you, it'll burn you. Then, the, the shockwave, which is moving at the speed of sound, rather than the speed of light, follows the light, and that's what, what comes later, and then breaks everything apart.

• 31:03Speaker 01

  Right.

• 31:04Neil deGrasse Tyson?

  Then you get the, the air, the expanding air, which then blows everything into the winds. All we are is dust in the wind.

• 31:14Speaker 01

  Dust.

• 31:15Neil deGrasse Tyson?

  Yes.

• 31:15Speaker 01

  Wind.

• 31:15Neil deGrasse Tyson?

  So they got that right, the three forces that operate in the aftermath of a nuclear explosion.

• 31:20Speaker 02

  So that made you happy?

• 31:21Neil deGrasse Tyson?

  Well...

• 31:21Speaker 02

  You weren't confronting, confronting anybody at a dinner party later.

• 31:24Neil deGrasse Tyson?

  In the face of having to show something that disastrous, yes, they got their physics right.

• 31:28Speaker 01

  That damn scene gave me nightmares for like, a month.

• 31:29Neil deGrasse Tyson?

  Yes, pretty creepy.

• 31:30Speaker 01

  And Neil's giggling. Well, the nuclear explosion was accurate.

• 31:33Neil deGrasse Tyson?

  So is there any physics you can tell me about, about the, the time travel?

• 31:39Speaker 01

  Well, they never really talk about it. I mean, the expanding sphere and all that, you know, that was pretty cool, but they never really talk about it. The idea that only living tissue can go through in time, but that's just a...

• 31:47Neil deGrasse Tyson?

  That bugged me though, because you're...

• 31:48Speaker 01

  That's a plot device.

• 31:49Neil deGrasse Tyson?

  Wait, wait, wait, I even tweeted this, your hair is dead, so he would've come back bald.

• 31:53Speaker 01

  Right, yeah, I remember thinking that as well, and like, your fingernails, and, and basically your outer layer of skin.

• 31:58Neil deGrasse Tyson?

  Yeah, yeah, so he'd be, he'd be...

• 32:01Speaker 02

  He looked like he'd been loofahed.

• 32:01Neil deGrasse Tyson?

  He would be, his, his...

• 32:03Speaker 01

  But you know...

• 32:03Neil deGrasse Tyson?

  His, his, he'd be loofahed. Yeah, he would be all dermis instead of epidermis.

• 32:08Speaker 01

  But Reese actually says something about, there's something about the energy field generated by a living body, so maybe that encompasses your hair. Now, I don't have to worry about that, being relatively hairless myself.

• 32:19Neil deGrasse Tyson?

  Okay.

• 32:20Speaker 01

  But the movie, the beauty of it is that the plot all holds together. It's not just somebody traveling back in time and then doing stuff. The movie, the time travel is part of the movie. Reese has to go back in time to impregnate Sarah Connor so that she can give birth to John Connor. And he has, I love it when he has the picture of her.

• 32:40Speaker 02

  Yes, I love that.

• 32:41Speaker 01

  And he's looking at that picture and he says, "I always wondered what she was thinking at that moment when this picture was taken." And at the end of the movie.

• 32:46Neil deGrasse Tyson?

  That's the moment.

• 32:47Speaker 01

  She's thinking of him. I mean, in a movie with Arnold Schwarzenegger and all this, and I'm like getting choked up. Come on, that was so weird.

• 32:53Neil deGrasse Tyson?

  Actually, that's not what I thought she was thinking. I thought she was just terrified of what was in her future. I wasn't getting all interpersonal about it.

• 33:00Speaker 01

  About how she was, but she was saying, you know, "You'll never know your father" or something, but she was actually thinking about Kyle.

• 33:06Neil deGrasse Tyson?

  So just to get the genetics of this straight.

• 33:09Speaker 01

  Yes.

• 33:09Neil deGrasse Tyson?

  He is his own father?

• 33:12Speaker 01

  He's John Connor's father.

• 33:14Neil deGrasse Tyson?

  So he's John Connor's son, but he begat John Connor?

• 33:18Speaker 02

  No, no, no, no, no.

• 33:19Speaker 01

  No, no, no. John Connor is Kyle Reese's son, but he goes back in time, gets Sarah Connor pregnant, she gives birth to John Connor, and then John Connor has to send his father back in time.

• 33:31Speaker 02

  To be his father.

• 33:32Neil deGrasse Tyson?

  So that he could exist.

• 33:33Speaker 01

  Yes. And that's why the movie is so tight, and in fact, it's probably the only movie in the history of movies where the sex scene is in fact integral to the plot.

• 33:42Neil deGrasse Tyson?

  Huh?

• 33:43Speaker 01

  Yeah. You know, they had to say-

• 33:44Speaker 02

  Take that, censors.

• 33:45Speaker 01

  Sorry, Ms. Hamilton, you gotta do it.

• 33:47Neil deGrasse Tyson?

  You gotta get laid wherever that, make it happen. Yeah. Okay, very cool.

• 33:53Speaker 01

  And that line has never worked for me, though. Come with me if you want to live, you know, and that doesn't actually work at the bar, sadly.

• 34:00Speaker 02

  Now, oh, was that one of the lines that you guys missed from the movie?

• 34:02Speaker 01

  No, actually Reese says that.

• 34:03Speaker 02

  Oh, darn it, you're right.

• 34:04Speaker 01

  The Terminator says that in the second movie, which is an homage to the first movie.

• 34:08Speaker 02

  Yes, yes.

• 34:08Neil deGrasse Tyson?

  You got it, you got it. So, any time travel movies I've left out? I mean, those are good.

• 34:14Speaker 01

  Well, uh-

• 34:16Neil deGrasse Tyson?

  Well, Back to the Future, that's worth its own segment. I want to save that for the last segment of StarTalk. Yeah, yeah, yeah. So, with all this time travel-

• 34:25Neil deGrasse Tyson?

  So what we're confessing here, or recognizing here, is that they don't put much physics into time travel, they just assert that it can exist, and then tell their stories behind it, right?

• 34:35Speaker 01

  I think that's pretty close.

• 34:36Neil deGrasse Tyson?

  How about Somewhere in Time? Do you remember that? Once again, Chris Reeve.

• 34:39Speaker 01

  I haven't actually seen it.

• 34:40Speaker 02

  Is that the one where he falls asleep, holding the penny, and he's thinking really hard?

• 34:45Neil deGrasse Tyson?

  So that's time travel, a chick flick time travel, that's what that was.

• 34:48Speaker 01

  Yeah, which is probably why I've never seen it.

• 34:50Neil deGrasse Tyson?

  It was romantic, it was.

• 34:52Speaker 02

  It was.

• 34:53Speaker 01

  My wife wants me to see that movie, and it's like, I...

• 34:56Speaker 02

  Dude, that's major points.

• 34:57Speaker 01

  Aliens, no? Rockets, no?

• 34:59Neil deGrasse Tyson?

  Yeah, there's no explosions, there's no aliens, there's no tidal waves.

• 35:03Speaker 02

  But it's love, it's the strongest force in the universe.

• 35:05Neil deGrasse Tyson?

  Love being that which brings you back through time.

• 35:08Speaker 01

  So...

• 35:09Neil deGrasse Tyson?

  What I liked about it was, and because I've thought about this often, if I go back through time, I need currency of the period. I can't, I cannot bring a teddy, a Roosevelt dime back to a pre-Roosevelt era and spend that money and have anyone think it's real money.

• 35:25Speaker 01

  That's right.

• 35:26Neil deGrasse Tyson?

  You need cash serving the time that you're in. And they did this in Star Trek, because they had a wardrobe, they said, yeah, wear this and wear that. And of course, my favorite line back in the Star Trek IV was when Spock gets on the bus...

• 35:40Speaker 01

  Yeah, yeah.

• 35:41Neil deGrasse Tyson?

  And then he gets off the bus, and he's, "What is exact change?" And I said, "Spock, aren't you smart enough to at least done your homework and figure this out?"

• 35:49Speaker 01

  No, that's not the problem, he did too much LDS at Berkeley.

• 35:51Neil deGrasse Tyson?

  Is that what that is?

• 35:52Speaker 01

  Well, that's what Kirk said.

• 35:53Neil deGrasse Tyson?

  We've got to take a quick break, but more StarTalk when we return.

• 36:20Neil deGrasse Tyson?

  This is StarTalk Radio, welcome back. The most recent time travel movie I can think of is Hot Tub Time Machine.

• 36:28Speaker 01

  Yeah.

• 36:28Neil deGrasse Tyson?

  Did you see that film?

• 36:29Speaker 01

  Yes, I did.

• 36:29Neil deGrasse Tyson?

  I did not. Tell me about the science in that film.

• 36:31Speaker 01

  It's actually one of the most scientifically accurate movies I have ever seen.

• 36:36Speaker 01

  Yeah, this endorsement paid in full by whatever studio made that movie.

• 36:40Neil deGrasse Tyson?

  Surely, something in the interaction of the alcohol and the circuit board could have turned the tub into a time machine.

• 36:45Speaker 02

  That's what I'm thinking. The right alcohol content, the electricity, the marriage of the two. It's fantastic.

• 36:50Speaker 01

  Whenever I'm in a hot tub and I spill a lot of alcohol on the control panel, I flash back to the 80s. So I think, actually, a factual basis to this.

• 36:58Neil deGrasse Tyson?

  Well, it can't be any more or less believable than a flux capacitor. Come on now.

• 37:03Speaker 02

  That's a better name.

• 37:04Speaker 01

  I have a flux capacitor. Uh, don't you?

• 37:08Neil deGrasse Tyson?

  I'm not authorized to.

• 37:10Speaker 01

  Oh, I see, I see. You have an entire planetarium, but not a flux capacitor. I see.

• 37:15Neil deGrasse Tyson?

  So let's talk, let's talk stuff about Back to the Future. First, it was, it's one of the great time travel movies of all time, I think. And is there any moments that, for each of you, that rise above the rest in the time travel aspects of the film?

• 37:30Speaker 01

  Wow, uh, that rise above. Well, yeah, sure, when, um, when, at the end of the movie, when he goes back to the future, there are subtle changes that happen. And I didn't even notice it the first time, in fact. It wasn't until I went to see the movie again.

• 37:46Neil deGrasse Tyson?

  Because he actually changed the future by having been in the past.

• 37:48Speaker 01

  Right, he, he, yeah.

• 37:51Neil deGrasse Tyson?

  So he changed his present?

• 37:52Speaker 01

  Yeah, by, by replacing his father in the tree, there's a series of events that cascades into the future. And so when he goes back to, back to the future, things are different. And they threw in-

• 38:02Neil deGrasse Tyson?

  So give me a list of some of those things that are different.

• 38:04Speaker 01

  Well, as he's leaving the barn, after he goes back into the past to 1955, he runs over one of the pines.

• 38:11Neil deGrasse Tyson?

  Because he restarts the DeLorean.

• 38:13Speaker 01

  Yes.

• 38:14Neil deGrasse Tyson?

  No, no, no. As he comes back through time, the DeLorean accidentally drives over one of the-

• 38:18Speaker 01

  No, no, no, he's-

• 38:19Neil deGrasse Tyson?

  Oh, he's coming back out?

• 38:20Speaker 01

  He comes back in time, he's in the barn, the farmer comes out and is gonna-

• 38:24Neil deGrasse Tyson?

  Shoot him.

• 38:25Speaker 01

  Shoot him, so he-

• 38:26Neil deGrasse Tyson?

  As farmers always do.

• 38:27Speaker 01

  Yes, yes.

• 38:28Neil deGrasse Tyson?

  At night, when you go into their barn.

• 38:30Speaker 01

  Exactly. And so, so Marty gets in, he starts the DeLorean up, crashes through the door, and runs over one of the pines. And you hear old man, whatever his name is, say, "My pine!"

• 38:40Neil deGrasse Tyson?

  And, and the, the, the estate sign that talked about the future real estate that would go there, described it as Twin Pines.

• 38:49Speaker 01

  Twin Pines Mall is the name of the mall where he and Doc Brown are testing out the DeLorean.

• 38:55Neil deGrasse Tyson?

  So we're, we're, we're to believe surely accurately that this mall was once this farmland.

• 39:00Speaker 01

  Yes. And so when he goes back to the future.

• 39:02Neil deGrasse Tyson?

  How hard is that to believe?

• 39:03Speaker 01

  Yeah, Christ. Yeah, well, you know, and he goes back to the future and you see the sign for the mall says, I, it was, I think it was Lone Pine Mall.

• 39:09Neil deGrasse Tyson?

  Lone Pine Mall.

• 39:10Speaker 01

  Yeah.

• 39:11Neil deGrasse Tyson?

  Instead of Twin Pine Mall.

• 39:12Speaker 01

  And I don't remember.

• 39:13Neil deGrasse Tyson?

  And they don't make a big deal of it, the camera just pans by it.

• 39:15Speaker 01

  And that's my favorite thing in a movie is where they, they just sort of toss something in there and let you figure it out for yourself.

• 39:20Neil deGrasse Tyson?

  That means you have to pay four times to see the movie.

• 39:22Speaker 01

  Yeah, well, yeah, I didn't notice that until the second time I saw the movie. And then I was, I was floored by this when I saw it.

• 39:27Neil deGrasse Tyson?

  I caught it like the fifth time, so it was a little slower than you.

• 39:29Speaker 01

  Really, but a really subtle.

• 39:30Speaker 02

  Yeah, yeah, I caught it.

• 39:31Neil deGrasse Tyson?

  No.

• 39:32Speaker 02

  Yeah.

• 39:33Speaker 01

  There, there is a continuity error that I caught right away.

• 39:36Neil deGrasse Tyson?

  Ooh.

• 39:37Speaker 02

  Really?

• 39:38Speaker 01

  That Marty, well Marty writes a note.

• 39:39Neil deGrasse Tyson?

  Yes.

• 39:40Speaker 01

  To Doc Brown and leaves it for him. And when Marty goes back to the future, and again, you know, spoiler alert here, uh, and, and Doc Brown opens up his, his jacket and as, there's a bulletproof vest and Marty says, "How did you know?" Doc Brown holds up the, the note, he taped it back together.

• 39:54Neil deGrasse Tyson?

  Yes.

• 39:55Speaker 01

  After tearing it apart. And the, the handwriting's different on the note. And I only remember that because Marty signed it and it went like across a crease or something and his signature was in a different place. And I, I remember sitting in the theater thinking, "Wow, the note's different." Uh, and my second thought was, "Wow, I'm a giant dork that I noticed that." Wow.

• 40:12Neil deGrasse Tyson?

  And were you alone in the theater when you saw the, yes, okay.

• 40:14Speaker 02

  But you know what, no, script supervisors get fired for that sort of thing.

• 40:17Neil deGrasse Tyson?

  Uh-oh, you just cost someone their job.

• 40:19Speaker 01

  Oh man, well, it was filmed, what, 25 years ago?

• 40:21Speaker 02

  Yeah, probably retired now.

• 40:23Neil deGrasse Tyson?

  So your point is this.

• 40:24Speaker 01

  Ah, that kid on the radio was.

• 40:26Neil deGrasse Tyson?

  You paid close enough attention to the original signature and noticed that it went across a crease in the paper.

• 40:30Speaker 01

  Or something like that. You'll see that the note is different.

• 40:32Neil deGrasse Tyson?

  A continuity, alright, any other, anything else you noticed?

• 40:34Speaker 01

  Fairly trivial error.

• 40:36Neil deGrasse Tyson?

  Yeah, that is as geek, I can't, I don't know if I can match that, I'll try hard, but go on, give me another one.

• 40:40Speaker 01

  Oh, I don't know.

• 40:41Neil deGrasse Tyson?

  No, no, it's just some more.

• 40:42Speaker 01

  You have something in mind?

• 40:43Neil deGrasse Tyson?

  Well, so, any other?

• 40:45Speaker 01

  There's no such thing as a flux capacitor.

• 40:47Neil deGrasse Tyson?

  Really?

• 40:48Speaker 02

  That we know of.

• 40:49Speaker 01

  Yeah.

• 40:50Neil deGrasse Tyson?

  That we know of. And, and I'm not authorized to, so.

• 40:52Speaker 01

  The idea of a DeLorean being unreliable seems fairly accurate.

• 40:55Neil deGrasse Tyson?

  Now, how about this?

• 40:56Speaker 02

  The lawyers are calling.

• 40:58Neil deGrasse Tyson?

  Have you heard anyone ever pronounce giga as jiga?

• 41:02Speaker 01

  Oh, yes, of course. Yeah.

• 41:04Neil deGrasse Tyson?

  You have?

• 41:05Speaker 01

  No, no, no.

• 41:06Neil deGrasse Tyson?

  I have never.

• 41:07Speaker 02

  Outside of rap songs?

• 41:07Neil deGrasse Tyson?

  Oh jig.

• 41:09Speaker 01

  Yeah, get Giga with it, I think is the...

• 41:11Neil deGrasse Tyson?

  Get jiggy with it.

• 41:12Speaker 01

  Yeah. Uh, no, and in fact, that really bugged me in the movie.

• 41:16Neil deGrasse Tyson?

  Yeah, he said jigawatt.

• 41:17Speaker 01

  Jigawatt, yeah.

• 41:18Neil deGrasse Tyson?

  Yeah, that's unfortunate. So how about, uh, here's something you might not have known.

• 41:24Speaker 01

  Alright.

• 41:24Neil deGrasse Tyson?

  Do you remember when Doc Brown is doing his, uh, wire tweaking in anticipation of the lightning bolt?

• 41:31Speaker 01

  Yeah.

• 41:31Neil deGrasse Tyson?

  Near the clock, and the cop comes up, okay?

• 41:34Speaker 01

  Mm-hmm.

• 41:34Neil deGrasse Tyson?

  And he says, "Do you have a permit for that?"

• 41:36Speaker 01

  Yes.

• 41:37Neil deGrasse Tyson?

  Okay, and then we just continue.

• 41:39Speaker 01

  Well, he pulls his wallet out and says, "Yeah, let me see if I have one here," and he's pulling out money.

• 41:42Neil deGrasse Tyson?

  He's pulling out money!

• 41:44Speaker 01

  Oh, I never noticed this.

• 41:46Neil deGrasse Tyson?

  He bribes, he, no, no, the reason why you didn't notice is because that scene was cut. It's in the DVD extras.

• 41:50Speaker 01

  I remember seeing that in the theater.

• 41:51Neil deGrasse Tyson?

  No, it was not in the theaters, no!

• 41:53Speaker 01

  Then I saw it on TV, I've not seen it on TV.

• 41:55Speaker 02

  Well, then you have a widescreen TV in your house, is what you're saying.

• 41:58Speaker 01

  I, I in fact do.

• 42:00Speaker 02

  See? There you go.

• 42:01Speaker 01

  But I never saw it on DVD, so I, and I know I've seen that scene, but I never do.

• 42:04Neil deGrasse Tyson?

  It was originally cut from the movie, and, uh, and I was kinda glad it was cut, because he's not a bribing kinda guy. You know, it was actually out of character with him.

• 42:11Speaker 01

  But he was very rich. I thought you were about to say he pulls money out, and it's modern money.

• 42:15Neil deGrasse Tyson?

  Oh, no, I didn't, I didn't look. I was shocked that he's bribing the cop, and that's how he can continue with this experiment.

• 42:19Speaker 01

  Well, I know I've seen that scene, I just don't know where, I mean, I've seen this movie for gazillion times.

• 42:24Speaker 02

  You saw it at the Planetarium.

• 42:25Speaker 01

  Four jigawatt times, and yeah, so I know I've seen it, but not on DVD, so maybe, uh, some version on television, they showed the DVD version.

• 42:32Neil deGrasse Tyson?

  And of course, my favorite is Mr. Fusion at the end there.

• 42:35Speaker 01

  That's awesome.

• 42:36Neil deGrasse Tyson?

  That's to- so good. The Mr. Fusion, that's how, in the future, rather than finding plutonium, which by the way, is an element named after Pluto, believed at the time it was named to have been a planet, discovered in 1940, 10 years after Pluto itself.

• 42:50Speaker 01

  I thought it was named after Plutarch, no?

• 42:52Neil deGrasse Tyson?

  So not! And they save the element after uranium for the name plutonium, so after neptunium. So you have uranium, neptunium, plutonium, three consecutive elements on the periodic table. Pluto got on the periodic table on false pretense.

• 43:09Speaker 01

  You're just waiting for Tysonian, aren't you? Tysonian, yeah.

• 43:14Neil deGrasse Tyson?

  So, I, we gotta wrap this up. This has been StarTalk Radio. I wanna thank my guests, and as always, I want to bid you to keep looking up.