Season 7 Time Capsule (Part 1)

Join host Neil Tyson as he revisits our fan’s favorite episodes from a season spent exploring Mars with Andy Weir, going back to the Moon with Buzz Aldrin, gazing into the future with Ray Kurzweil, listening for gravitational waves, and much more. NOTE: StarTalk All-Access subscribers can listen to this entire episode commercial-free. Find out more at https://www.startalkradio.net/startalk-all-access/

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.

• 0:14Neil deGrasse Tyson?

  Welcome to StarTalk. I'm your host, Neil deGrasse Tyson, your personal astrophysicist. I'm also the director of New York City's Hayden Planetarium at the American Museum of Natural History. This week, we're bringing in a new year and preparing to launch yet another season of StarTalk Radio. But first, we'll say goodbye to 2016 and our seventh season. Yes, seventh season. We'll do that with the first part of our annual time capsule show. Every year, we send out a survey to you, our fans, and ask you to vote for all your favorite episodes, your favorite guests, your favorite co-hosts. Then, we cut and splice to create

• 0:57Neil deGrasse Tyson?

  this single mashup episode of The Winning Picks. 2016 saw our third season on the National Geographic Channel, and it would be StarTalk TV's second Emmy nomination. And every episode is an opportunity to reveal and expose the geek underbelly of the pop culture stars and influencers all around us. And it's what we do here on StarTalk. And with your help, we're able to select some of these best moments from our past season. First up, The Lunar Legacy with the living legend Buzz Aldrin. He was the lunar module pilot on Apollo 11. He landed on the moon with Neil Armstrong back in 1969. I remember

• 1:40Neil deGrasse Tyson?

  that. That's how old I am. And he's the second man to walk on its surface. I interviewed Buzz inside my office here at the Hayden Planetarium. Co-host Eliza Schlesinger helped me out in the studio, along with science guest, the former astronaut Mike Massimino, although can you ever really be a former astronaut? Mike was also selected as one of your favorite guests of the season. Let's see what they had to say.

• 2:06Neil deGrasse Tyson?

  Buzz was the first to pee in space.

• 2:08Speaker 01

  I think he was the first to pee on the moon.

• 2:10Neil deGrasse Tyson?

  Pee on the moon?

• 2:10Speaker 01

  Yeah, because other guys peed in space. I think that's how other countries know that we were there. I think he was the first.

• 2:17Neil deGrasse Tyson?

  Buzz, USA!

• 2:20Speaker 01

  Yeah, I don't think they held it for, you know, for...

• 2:22Neil deGrasse Tyson?

  You can't hold it for three days.

• 2:24Speaker 01

  No. Two weeks, Jim Lovell was up there, I'm sure he peed. Not that I ever have, but I'm sure, you know...

• 2:30Neil deGrasse Tyson?

  He's the first to pee on the moon.

• 2:31Speaker 01

  Yeah, I think it was on the moon.

• 2:32Neil deGrasse Tyson?

  On the moon, and you have a space first?

• 2:35Speaker 01

  I do.

• 2:36Neil deGrasse Tyson?

  Yes, what is that?

• 2:37Speaker 01

  I was the first to tweet from space.

• 2:39Neil deGrasse Tyson?

  To tweet from space?

• 2:39Speaker 01

  Yes, I was the first.

• 2:41Neil deGrasse Tyson?

  Very cool.

• 2:41Speaker 01

  Tweet from space, what do you think of that? That's pretty great! Yeah, not like walking on the moon. No. Maybe closer to peeing on the moon. What was the tweet, like, how does this work?

• 2:50Neil deGrasse Tyson?

  No, don't, yeah, yeah, don't ask him. Because we'll be prone to compare it to one small step for man. One giant leap for mankind.

• 2:58Speaker 01

  That's exactly what happened on Saturday Night Live. They made fun of me based on that quote. And, all right, so what happened was I tweeted, "Launch was awesome."

• 3:09Speaker 01

  And I wanted the people of Earth to know I was okay, so I said, "I'm feeling fine." Right, and then I put... I'll do it. "The adventure of a lifetime has begun." So, and this is... Yes, this is what I... All right, you know, I was in space.

• 3:25Neil deGrasse Tyson?

  What's your favorite story that you're telling here that you want the public to know?

• 3:30Speaker 02

  First guy to pee in his pants on the moon.

• 3:33Neil deGrasse Tyson?

  I was gonna ask you about that, because I have kids come up to me, "How do astronauts poop and pee?" So, because I looked inside the command module of the Apollo command module. There's no restroom that you get up and go to.

• 3:46Speaker 02

  You know, Alan Shepard's flight was gonna be a pretty short one. So he was supposed to go out there, get in this Mercury, first time, first American, submer. And the launch countdown didn't quite go the way it was expected. There was delay, delay, delay.

• 4:15Speaker 02

  And Alan's lying on his back. Pretty soon it's getting pretty damp there. And that's when they figure, we gotta do something. We gotta have a little bit better hydraulic engineering into the space suit and the rest of it.

• 4:35Neil deGrasse Tyson?

  So what they call it, hydraulic engineering?

• 4:38Speaker 02

  The UCD, very important, urine collection device.

• 4:44Neil deGrasse Tyson?

  Okay.

• 4:45Speaker 02

  And the UCD.

• 4:47Neil deGrasse Tyson?

  Somehow I thought those words would be bigger. It's just, it's your pee collection device, that's all it is.

• 4:53Speaker 02

  It gets dumped overboard and it freezes me.

• 4:58Neil deGrasse Tyson?

  Instantly, yeah.

• 4:59Speaker 02

  And there are flakes.

• 5:01Neil deGrasse Tyson?

  But doesn't the pee say?

• 5:02Speaker 02

  There are flakes outside.

• 5:03Neil deGrasse Tyson?

  Wait, wait, wait, the pee is moving the same speed as your ship.

• 5:06Speaker 02

  Of course it would.

• 5:07Neil deGrasse Tyson?

  Right, so if you put it outside, now the pee is, frozen pee, is traveling alongside with you to the moon.

• 5:14Speaker 02

  Scott Carpenter saw a lot of those fireflies.

• 5:21Speaker 02

  And he was so fascinated with them that he wasn't quite lined up for retro fire. He got the cosine of it, which is, you know, enough. But there was a little bit of the sine of the angle that he saw. That's why he landed.

• 5:42Neil deGrasse Tyson?

  In the wrong place.

• 5:43Speaker 02

  Not where he was supposed to go.

• 5:44Neil deGrasse Tyson?

  But the fireflies, are you telling me that was his pee?

• 5:47Speaker 02

  Yeah, it was a urine dump.

• 5:50Neil deGrasse Tyson?

  Okay, the mysterious fireflies.

• 5:55Speaker 02

  But there was a little hesitancy about people are getting their jewel too close to what was gonna go to a vacuum, like they might get sucked outside.

• 6:20Neil deGrasse Tyson?

  So, we have to ask, Mike.

• 6:22Speaker 01

  Yes.

• 6:23Neil deGrasse Tyson?

  Have you ever peed in your pants, in space?

• 6:25Speaker 01

  Yes. We didn't call it the UCD, we called it the MAG.

• 6:30Neil deGrasse Tyson?

  The MAG?

• 6:31Speaker 01

  The Maximum Absorbency Garment. It was a diaper.

• 6:35Neil deGrasse Tyson?

  Diaper!

• 6:36Speaker 01

  Yes, we wore a diaper on launch and entry and while spacewalking. And then when you're inside the spacecraft, you use the toilet.

• 6:43Neil deGrasse Tyson?

  Okay, so where does the pee go if you do it in the spacecraft?

• 6:47Speaker 01

  In the spacecraft, it's collected and then dumped, as he described. And you would want to see, the urine dump was cool. Because it would, you would dump it, and it would crystallize, and the sun would shine on it, and it was really fun. It was, it was something.

• 7:00Neil deGrasse Tyson?

  I can't believe I'm having a conversation about beautiful frozen pee in space!

• 7:05Speaker 01

  Hey, everybody, it's a urine dump! I, I, hey, it's a urine dump! And, you know, before you hit the switch, everyone go to the window and watch. That's it.

• 7:13Neil deGrasse Tyson?

  So you're telling me your pee was orbiting the Earth?

• 7:17Speaker 01

  Apparently, yes. I never thought of it that way, but yes, for a little bit, until it crystallized, you know, it kind of disappeared.

• 7:21Neil deGrasse Tyson?

  No, then it would re-enter the atmosphere.

• 7:23Speaker 01

  Uh, well?

• 7:25Neil deGrasse Tyson?

  Yes, yes.

• 7:26Speaker 01

  Okay, yes, I, eat on everybody!

• 7:29Neil deGrasse Tyson?

  You peed, you peed on Earth! Oh my gosh! Some of the most interesting and disputed scientific inquiry lies in the realm of artificial intelligence. Will machines develop consciousness? Should humans be worried about it? I'm not really worried about it. But maybe I should be. I interviewed futurist, author, and inventor Ray Kurzweil. Finally got to meet the guy, just to tackle this discussion in the season seven premiere, Gazing Into the Future. I was joined in studio by my comic co-host Chuck Nice and neuroscientist Gary Marcus. Check it out. Well, okay, so, whether it's AI taking over us,

• 8:11Neil deGrasse Tyson?

  or we controlling AI for evil, nefarious purposes, there, no doubt that there are existential threats that this technology can bring. And I asked Ray, of course, I had to ask Ray about this, check it out.

• 8:26Speaker 03

  Technology's been a double-edged sword ever since

• 8:29Neil deGrasse Tyson?

  It's ever been.

• 8:30Speaker 03

  Fire. I mean, fire kept us warm, but burned down our houses. Every technology can be used for creative and destructive purposes. We have actually a new technology that has an existential risk already, which is biotechnology. The existential risk from artificial intelligence or nanotechnology is off in the future. And we can debate, is it 10 years away or 50 years away? But it's not here yet. But the ability for someone to take a benign virus, like a cold virus, and turn it into a superweapon, to make it more deadly, more communicable, more stealthy, exists right now. That could be done in a biotechnology lab probably a few blocks from here. So that was recognized, actually, 30 years ago.

• 9:15Speaker 03

  And they had a conference called the Asilomar Conference to come up with guidelines, how can we keep this safe and reap the promise without the peril? And they came up with the Asilomar Guidelines. Those have been made more sophisticated over time. And they've worked very well. We're now reaping the benefits of biotechnology. The number of incidents, either intentional or accidental, that there's been harm from biotechnology so far is

• 9:38Neil deGrasse Tyson?

  Near zero.

• 9:39Speaker 03

  It's zero.

• 9:40Neil deGrasse Tyson?

  Yeah.

• 9:40Speaker 03

  Now, that doesn't mean we can cross it off our worry list because the technology keeps getting more sophisticated. But nonetheless, it's actually a good model for how to keep these technologies safe.

• 9:50Neil deGrasse Tyson?

  Well, plus, you know, when we know that fire exists, and so we have fire codes, right? This is how you build a stairwell, and this is how you escape. And this is how

• 9:57Speaker 03

  And we have a moral imperative to use fire or artificial intelligence or biotechnology to overcome the problems, you know, that humans have. There's still a lot of human suffering. And we're using AI to diagnose disease and come up with new cures and clean up the environment to reduce poverty. And we have a moral imperative to continue that way while we, you know, have ethical guidelines to keep the technologies as safe as possible.

• 10:26Neil deGrasse Tyson?

  So Gary, you're quite prolific on this topic in the popular media, even not only professionally. So one of your articles for The New Yorker cited why we should think about the threat of artificial intelligence. So that sounds very ludidic.

• 10:43Speaker 04

  I'm no ludite. In fact, I'm just launching an organization called AI4Good.org, which is about what positive outcomes we can get from AI. But there are also risks too, and it's a trade-off, right?

• 10:55Neil deGrasse Tyson?

  But ethical guidelines enough to just guide this, because we have ethical guidelines for everything else that could possibly kill us.

• 11:01Speaker 04

  I probably need regulation too. I mean...

• 11:03Neil deGrasse Tyson?

  Yeah, regulation, but we do that. We don't say, "Let's not have airplanes because they could crash." We have regulations to make them as safe as possible. And they still crash, but we accept that risk. So...

• 11:11Speaker 04

  That's right. And I mean, we do some kind of calculus to decide whether it's worth it. And maybe that 200 years from now, people look at us and like, "Why did they use cars before they had computers in them to make them safe? They've lost so many people." And so people may look back at us now and say, "The ways in which we handled AI in 2150, in their early days, we're really pretty poor." And so I don't know what the regulations are going to be. It's probably going to be iterative. One of the things that I think we all worry about is that the pace could be fast and we don't have enough time to take care of it.

• 11:42Neil deGrasse Tyson?

  Do you share the total concern that the famous, you know, trinity of Elon Musk, Bill Gates, and Stephen Hawking have shared?

• 11:50Speaker 04

  No, I have a milder view. I mean, I think that real strong AI is...

• 11:54Neil deGrasse Tyson?

  Just to be clear, they're like freaking out.

• 11:57Speaker 04

  Right. They think that basically machines are going to take over and kill us all.

• 12:00Neil deGrasse Tyson?

  Kill us all. And then the future of the world is a world of machines.

• 12:03Speaker 04

  A world of machines.

• 12:04Neil deGrasse Tyson?

  Right, right.

• 12:04Speaker 04

  I don't think it's right.

• 12:07Speaker 04

  Honest truth...

• 12:08Neil deGrasse Tyson?

  The Terminator.

• 12:11Speaker 04

  The machines are coming. Okay. The honest truth is that Skynet is not going to be here tomorrow.

• 12:18Neil deGrasse Tyson?

  You're going to have an Austrian accent.

• 12:19Speaker 04

  All the machines will have an Austrian accent. "Look at this, I'm going to kill you." I'm sorry, go ahead. I don't think that the Schwarzenegger version of it's going to be here anytime soon. I don't think the computers care about us so far. You get computers that are exponentially smarter at playing chess, and they don't give a shit about us at all. I don't know if I can say that on the air. But at the same time, I still think we need to be worried. As computers get more and more embedded in our lives, they have more and more power to change things. So they're going to start driving our cars, for example. And if the AI isn't right, then there's a risk there.

• 12:51Neil deGrasse Tyson?

  When the critically acclaimed film The Martian hit the box office in 2015, it became what is perhaps the most scientifically accurate science fiction film ever made. And it was wildly successful. The film was, of course, based on the bestselling novel of the same name, written by Andy Weir. So I snagged Andy for an interview to talk with the man behind the phenomenon. And it's no surprise, this episode was voted as your number one favorite of season seven. I was joined in studio by NASA engineer Adam Steltner, who led the entry descent and landing team of the Mars Curiosity rover. You might remember that several minutes of hell video that went viral.

• 13:34Neil deGrasse Tyson?

  Well, he was in charge of making that happen. Also, hear from first time co-host Matt Kirschen. Check it out. Part of Mark Watney's survival was knowing where past sources of energy and rocket ships and because we'd been to Mars before.

• 13:50Speaker 05

  Right.

• 13:51Neil deGrasse Tyson?

  And so then he, so he's got to get around. And so he's got a rover.

• 13:56Speaker 05

  Yeah, he goes to the Ares IV eventual landing site where they have sent.

• 14:01Neil deGrasse Tyson?

  Because this was Ares III.

• 14:03Speaker 05

  He was on Ares III. Ares IV, they had already sent the Mars ascent vehicle and it was sitting there making its fuel and, and all the pre-supplies hadn't come yet, but they had sent the M A V. And so Mark.

• 14:15Neil deGrasse Tyson?

  By the way, which is a completely sensible way to do future space exploration.

• 14:19Speaker 05

  Yeah.

• 14:20Neil deGrasse Tyson?

  You just send supplies separately, no reason to risk lives doing that. And then you send astronauts later.

• 14:26Speaker 05

  Once you've confirmed that the supplies made it okay.

• 14:28Neil deGrasse Tyson?

  Yes, and then they can, then they can pitch tent and set up and play house.

• 14:31Speaker 05

  Mm-hmm, yeah. And so he realized that there's a spaceship capable of getting him into low Mars orbit right there on Mars. He just needs to get to it. The bad news was it was 3,200 kilometers away.

• 14:42Neil deGrasse Tyson?

  Right.

• 14:43Speaker 05

  So he had to take these rovers, which were really designed for a 20 kilometer range before being recharged and drive 3,200 kilometers. So it's quite a challenge.

• 14:53Neil deGrasse Tyson?

  Well, Adam, you led a team, Curiosity, a car-sized rover, to move on the surface of Mars.

• 14:59Speaker 06

  Yep.

• 15:00Neil deGrasse Tyson?

  What would it take to drive that 3,200 kilometers?

• 15:04Speaker 06

  A very, very long time.

• 15:07Neil deGrasse Tyson?

  Actually...

• 15:08Speaker 06

  So, it's true. She's only gone 13,992 meters in four years.

• 15:17Neil deGrasse Tyson?

  See, he used meters, now the number sounds bigger, right? You got that?

• 15:20Speaker 06

  A whopping 13,000...

• 15:22Speaker 05

  Every guy knows that trick.

• 15:23Neil deGrasse Tyson?

  Yeah, yeah, it's a trick. It's a trick. It's 13 kilometers. If you do it in miles, it's even less. It's like eight miles, okay?

• 15:31Speaker 06

  But we're not, unlike Mark Watney, we're not hitting the gas and trying to get somewhere. We are actually, well frankly, scienceing the [BLEEP] out of Mars along the way.

• 15:40Neil deGrasse Tyson?

  Okay, because you're not in a hurry.

• 15:42Speaker 06

  We're not in a hurry. We're exploring. We're looking at the surface of Mars. We're learning about its history. We're learning about its ancient environment. We're searching for the possibility that it could have supported life.

• 15:53Neil deGrasse Tyson?

  Okay.

• 15:54Speaker 06

  But as evidence of how slow and how methodical and interested our science team is, we went to the Gale Crater for some clay minerals that we saw from orbit. Signatures of clay minerals.

• 16:08Neil deGrasse Tyson?

  So clay is where there was water and deposits that settle, and then you disperse for the non...

• 16:12Speaker 06

  Yeah, like the bottom of a lake bed kind of feel. We still haven't got to that deposit that we saw in the entire time that we've been on Mars, and yet we've done a whole...

• 16:22Neil deGrasse Tyson?

  Because you've been busy.

• 16:23Speaker 06

  Because we've been busy.

• 16:24Speaker 05

  Because it's been stopping for pee breaks.

• 16:27Neil deGrasse Tyson?

  All right, so, so, let's back up for a minute. Because your specialty was getting the thing there safely.

• 16:33Speaker 06

  Yes, sir.

• 16:33Neil deGrasse Tyson?

  So that the scientists could do their job. And so, what I remember from Spirit and Opportunity, the previous round of this, they had, like, airbags.

• 16:44Speaker 06

  Yep.

• 16:45Neil deGrasse Tyson?

  So the thing comes down, and airbags deploy, and it bounces until it stops. Now you have Curiosity, because those were the size of, like, microwave ovens, let's say.

• 16:53Speaker 06

  Yes.

• 16:54Neil deGrasse Tyson?

  Okay, so Curiosity is the size of a car.

• 16:56Speaker 06

  Yeah.

• 16:56Neil deGrasse Tyson?

  And why not use airbags again?

• 16:58Speaker 06

  So there are no fibers known to humankind from which we can make a fabric, from which you can make a bag that could handle the loads of that car-like rover hitting the surface of Mars.

• 17:07Neil deGrasse Tyson?

  Okay, so now, actually, you used what I told is called a sky crane.

• 17:11Speaker 06

  Yes.

• 17:11Neil deGrasse Tyson?

  This sounds complicated. What is that? It's like a jetpack?

• 17:15Speaker 06

  It's like a jetpack. The rover was sort of wearing a jetpack, and then about... Twenty-five meters from the surface of Mars, the jetpack lowers the rover below it, and the two descend until the rovers. OK, I think we have a video of this. Can you be the narrator voice of this? I will absolutely narrate this, yes. Drew, you got the video? Let's check it out. OK, talk us through it. All right, so we hit the atmosphere going quite quickly, about 13,000 miles an hour. That's fast enough to burn up or melt the whole spacecraft. That would be uncool. So we wrap it in a special shell. We actually steer our way through the atmosphere. This was the first for this expedition. And that's where you see those rockets going off. We're actually maneuvering in the atmosphere. And then, when we've slowed down to about,

• 18:00Speaker 06

  oh, a little less than 1,000 miles an hour, we open up a parachute. In our case, the world's largest supersonic parachute. We open it up in Mach 2. We get rid of the heat shield that protected us from atmospheric entry. And then we let go,

• 18:17Speaker 06

  and we go on to rockets.

• 18:21Speaker 06

  Now you can see a rover with its wheels. There's six wheels. They're all sort of tucked up, and it's got this jet backpack on top of it. It's slowly descending into the Gale Crater.

• 18:37Speaker 06

  We're looking at the ground with a radar. And then, here we do the sky crate maneuver. We lower the rover below us, drop the wheels down. Both vehicles continue to descend until Mars takes up the weight of the rover. We sense that, cut ourselves free, and fly off to a safe distance.

• 19:23Neil deGrasse Tyson?

  Welcome back to StarTalk Radio. This special time capsule episode is a mashup of your favorite moments from all of season seven. You cast your votes, and as always, it was a tight race, but the results are in. You selected "The Beauty of Mathematics" as one of your favorite episodes. We take an in-depth look at the film "The Man Who Knew Infinity." It's a movie about the life and struggles of one of the most brilliant minds of the history of mathematics, self-taught math genius Ramanujan. Actor Jeremy Irons and director Matt Brown joined me in my office to talk about the movie and how science has affected their own lives. I was joined in studio by co-host Eugene Mirman, as well as the movie's own science consultant,

• 20:07Neil deGrasse Tyson?

  mathematics professor Ken Ono. This film is about a self-taught math genius from India and an English math professor. And so I had to ask Jeremy about that special relationship that he had to create in that film. Let's check it out.

• 20:23Speaker 07

  We tend to sort of rather generalize black and white in relationships, but there's a myriad of types of relationship. And this was, I think, a very heartfelt, you could say, father-son. I don't know, it wasn't really that, but it was the relationship of two men who had the same dreams, who had the same passions for their subject. And that brings you really close to somebody. He describes it as being the greatest, well, the only romantic period of his life, but I think that was romance. Yeah, it was a different idea of romantic. Sexual romance.

• 21:02Neil deGrasse Tyson?

  Yeah, of course, of course.

• 21:03Speaker 07

  It was romance for sharing a dream and a time of his life when there was color and brilliance that later on in life he looks back on as having been the great period of his life.

• 21:17Neil deGrasse Tyson?

  So Ken, it's an intellectual romance.

• 21:19Speaker 08

  It is.

• 21:19Neil deGrasse Tyson?

  And that's kind of what makes it a more interesting story to tell. Otherwise...

• 21:23Speaker 08

  That's really what the film is about.

• 21:24Neil deGrasse Tyson?

  That's what it's doing, and why you have someone, the likes of Jeremy Irons, to portray.

• 21:29Speaker 08

  It's great, isn't it?

• 21:30Neil deGrasse Tyson?

  It is great. Just hearing him talk, I mean, come on.

• 21:32Speaker 08

  Yeah, yeah, yeah.

• 21:32Speaker 09

  He seems very charming. I would like to be his friend.

• 21:36Neil deGrasse Tyson?

  So, what else can you tell us about Romanujin's relationship with G.H. Hardy?

• 21:42Speaker 08

  Well, it's actually a very complicated relationship.

• 21:44Neil deGrasse Tyson?

  And do we know about this relationship?

• 21:45Speaker 08

  We know a lot about it.

• 21:46Neil deGrasse Tyson?

  Romanujin's writings, or is it from G.H. Hardy's writings?

• 21:49Speaker 08

  From both.

• 21:49Neil deGrasse Tyson?

  Both.

• 21:50Speaker 09

  Did they share a diary?

• 21:52Speaker 08

  Not to share, they did not share a diary, but there are, many of the letters between them still survive. So it's actually very interesting. At first, Romanujin needed help from his mentor Hardy. And at first Hardy viewed himself as the great Cambridge professor who could offer that help. But over time Hardy began to recognize more than just Romanujin's creativity, it's just sheer the volume and the work that he could produce. So, that relationship went from mentor-student to almost being like equal partners, teammates. And it's beautifully told in this film. That human element is something you can't deny, right? It's not about...

• 22:33Neil deGrasse Tyson?

  This is the great transition that someone makes. And it's not always easy, and not everyone survives that transition. They can't...

• 22:39Speaker 08

  That's right.

• 22:39Neil deGrasse Tyson?

  They can't make that change from learning to the one who then becomes the teacher.

• 22:45Speaker 08

  That's right, that's right.

• 22:46Neil deGrasse Tyson?

  But you turn out okay.

• 22:48Speaker 08

  Thank you very much.

• 22:50Speaker 09

  From the limited information we have.

• 22:53Neil deGrasse Tyson?

  Gene, do comedians mentor other comedians?

• 22:56Speaker 09

  Very much so, yeah.

• 22:57Neil deGrasse Tyson?

  Really?

• 22:58Speaker 09

  Yeah, because you...

• 22:59Neil deGrasse Tyson?

  So is this someone you can claim that we can look to and say, "Hey, that's a Eugene prodigy"?

• 23:04Speaker 09

  Jerry Seinfeld is someone I helped out a lot.

• 23:09Speaker 09

  No, but there's a lot of comics, like Patton Oswalt helped me a lot, David Cross, Michael Showalter, and David Wayne, Michael Ian Black, a lot of people. And then there's comics that you bring on the road with you. So yeah, that's very much the world of comedy, is a lot of people sort of helping each other.

• 23:27Neil deGrasse Tyson?

  Well, Jeremy Irons plays math mentor in The Man Who Knew Infinity. And I just, I had to ask him, how did he prepare for that role? Let's find out. As an actor, when you play someone who is learned, or is a scientist, in ways that you are not that, what do you reach for to make it happen?

• 23:46Speaker 07

  You, you...

• 23:46Neil deGrasse Tyson?

  But you gotta read all the books that he read. I mean, how does this work?

• 23:48Speaker 07

  Well, we had Ken Ono.

• 23:51Speaker 10

  Yeah.

• 23:51Speaker 07

  And I said to Ken, because great mathematician, I said to Ken,

• 23:54Neil deGrasse Tyson?

  Oh, as, as an advisor?

• 23:56Speaker 10

  That's right.

• 23:56Neil deGrasse Tyson?

  See, this is a trend line.

• 23:58Speaker 07

  Yeah.

• 23:59Neil deGrasse Tyson?

  You know, that didn't, there was a day that didn't happen, where people make movies and they just make stuff up.

• 24:04Speaker 07

  I know.

• 24:04Speaker 10

  Ken was incredible. He flew, I sent out an email to five different mathematicians. They all wrote back in five minutes. And Ken was on an airplane three days later, came to England and made sure every single piece of writing in the movie was right and accurate, so. And I think it gave these guys the...

• 24:19Neil deGrasse Tyson?

  Because they know I'm gonna be tweeting about the movie, and I'm gonna be calling them out if they can make it...

• 24:23Speaker 07

  That's right.

• 24:24Speaker 10

  No, they bash for it.

• 24:26Speaker 07

  Yeah, you've got to, when you, when you have to pretend to be able to do things that you know nothing about, you've gotta have something saying, "That is right. Believe me, that is right. What you're doing is right. That makes sense." Because you don't know, you can't tell. I mean, I know if it's, if it's something emotional, I know whether it's true or not, or what, I can judge that. But, so it was great to have Ken on this. And, and it gave me the confidence to say what I was saying, knowing that it was true and it was right.

• 24:54Neil deGrasse Tyson?

  So, Ken, you got a good shout out in that segment.

• 24:57Speaker 08

  I liked that very much.

• 24:58Neil deGrasse Tyson?

  We got the man himself in studio.

• 25:03Neil deGrasse Tyson?

  So, did you enjoy that experience?

• 25:05Speaker 08

  Oh, I loved it. Um, you know, I have no experience in film, so, uh, all of it was new to me. And I have a much greater appreciation now for how hard it is to make a film, produce a film, and then promote a film. It's been really interesting. And by the way, both Dev Patel and Jeremy Irons, they were great students. So they know a lot more than they pretend in these interviews. They're, they really elevate...

• 25:29Neil deGrasse Tyson?

  So how do you coach someone who knows no math to sound fluent in math?

• 25:33Speaker 08

  We spent a lot of time in rehearsals talking about math, talking about- How to pronounce all the equations. Oh my god, we, yeah.

• 25:40Speaker 09

  Did you have to teach the, like, teach them math? Like, meaning, did they actually learn a fair amount of math? Or were-

• 25:46Speaker 08

  No, they learned, they didn't learn any real mathematics from me.

• 25:50Speaker 09

  Well, in some movies, like, a person needs to learn how to-

• 25:52Speaker 08

  That's why they're called actors, okay?

• 25:54Speaker 09

  But in some movies, like, when someone's acting as, like, a drummer, they learned to drum. I get that if it's a movie of-

• 26:00Speaker 08

  Is that true?

• 26:00Speaker 09

  Yeah.

• 26:01Speaker 08

  Okay.

• 26:01Speaker 09

  Yeah, because that would be better than a guy doing this. And you're like, why does it still sound like music? But I guess with math-

• 26:10Speaker 08

  Uh, yeah, no, no, no. Yeah, but they've got it, they've got it, their, their, their phrasings of math expressions- Exactly. Has to come out right. We spent hours reworking about a dozen scenes just to get the language right, get the intonation of the sentences right. Even, we even practiced at a chalkboard how to write formulas so that you would emphasize the right, right strokes in equations. Most people probably won't notice this in the film, but mathematicians who've seen the film, they adore and embrace this part. But more, more likely, if you see a film where a person was not coached in how to write the equations- That's obvious. Oh, it's completely obvious. Terribly obvious.

• 26:46Speaker 09

  How about, uh, Matt Damon in Good Will Hunting? How are his equations? Ooh.

• 26:53Neil deGrasse Tyson?

  Next up, a StarTalk Live edition called LIGO and the Black Hole Blues. This show happened only a few months after the announcement of gravitational waves, the scientific discovery of the year, and possibly of the entire century. Although, there's still many more years of the century to come. My co-host Eugene Mirman and StarTalk Live guest comedian Michael Showalter join me on stage with theoretical astrophysicist Janna Levin and LIGO astrophysicist Nurgus Malvalva to help us understand everything we could ever want to know about gravitational waves.

• 27:30Speaker 11

  An nephrometer is an optical device where you take a laser beam and you kind of split it in two paths.

• 27:36Speaker 09

  Nice.

• 27:37Speaker 11

  And the light travels along two paths. And it comes back.

• 27:41Speaker 09

  Nice.

• 27:42Speaker 11

  And then it interferes.

• 27:43Neil deGrasse Tyson?

  You can save your emotions for after she finishes.

• 27:46Speaker 09

  You start with a laser, you break it up, you get them back together.

• 27:48Speaker 11

  Yep.

• 27:49Speaker 09

  And then you're like, now I get how gravity works.

• 27:51Speaker 11

  But along the way, what happened, when you broke the two laser beams apart, if they travel different distances, then when they come back together, they act a little funny. They're a bit darker or a bit brighter.

• 28:03Speaker 09

  And why do they travel a different distance?

• 28:05Speaker 11

  Because the gravitational wave came through the detector.

• 28:07Speaker 09

  Ah ha! I caught you! Now I get it.

• 28:12Neil deGrasse Tyson?

  Right, so what you have, so your two beams are otherwise identically the same length.

• 28:19Speaker 11

  Yes.

• 28:19Neil deGrasse Tyson?

  Now, a gravity wave washes across the detector and makes the length of one different from the length of the other.

• 28:27Speaker 09

  Because it went into the future.

• 28:28Neil deGrasse Tyson?

  And then you can recombine the waves, and now you have like a crest adding to a trough of these waves, and they interfere with one another, and you can measure this.

• 28:38Speaker 11

  We can measure that, and we can measure not just if crests line up with crests or crests line up with troughs, but lots of variations in between. So is it perfectly dark because troughs and troughs lined up? Or is it perfectly bright or something in between? And that's how we make the measurement. We actually use the laser beam along one arm as a kind of a reference for measuring the light travel time along the other arm. You just compare how long did the light take along this arm compared to the light along the perpendicular arm.

• 29:06Neil deGrasse Tyson?

  Now you've got two of these facilities. Why?

• 29:09Speaker 11

  Well, that's really important, because the...

• 29:12Neil deGrasse Tyson?

  And one is in Louisiana, one is in Washington State.

• 29:15Speaker 11

  Yep, yeah, so they're about 3,000 kilometers apart.

• 29:17Neil deGrasse Tyson?

  Convert that to miles here, because we're Americans here.

• 29:20Speaker 09

  Eight. Eight miles.

• 29:25Speaker 09

  Trust me.

• 29:30Neil deGrasse Tyson?

  So it's about 2,000 miles.

• 29:32Speaker 11

  Yes, thereabouts.

• 29:33Speaker 12

  You say 2,000, okay.

• 29:35Speaker 11

  So why do we need two of them? In fact, there's actually a European detector in Italy as well called Virgo. And why do we need so many? So a couple of things. One is the signals are very weak. And so how does this... Can I say how the detector works?

• 29:51Neil deGrasse Tyson?

  Yeah.

• 29:52Speaker 11

  Do you want to know how the detector works? Okay. Okay.

• 29:55Speaker 12

  They all get up and leave now.

• 29:58Speaker 11

  Wait, wait, stop. I'll stop.

• 30:01Neil deGrasse Tyson?

  Okay, as they start going for the exits.

• 30:03Speaker 12

  Yeah, we love to know how it works.

• 30:04Speaker 11

  So the way it actually works is that the gravitational wave comes through the detector. It actually changes the distance between the laser and a mirror. That in our case, in the case of LIGO, the US detectors, the mirrors and the lasers are separated by 4 kilometers. So 2 and 1/2 miles. Okay? So, and what happens then is that our job then is simply to measure the change in distance between the laser and the mirror when the gravitational wave goes by compared to when it's not there. And now the problem is that the motion of these mirrors compared to the laser distance is tiny. The gravitational wave is really, really, really weak.

• 30:47Speaker 11

  And so the motion we're trying to measure over those 2 and 1/2 miles is smaller than 1,000th the size of a proton. Okay, so it's a very small number. It's 10 to the minus 18 meters for those of you who think in those kinds of numbers. But really, what you have to think about is that you start off with an atom and you, you know, you get to something that's 1,000 times smaller than the typical size of an atom. You have its nucleus in the center, a proton. And now we're thinking of something that's 1,000 times smaller than the central nucleus of an atom.

• 31:22Neil deGrasse Tyson?

  And you measured that?

• 31:23Speaker 11

  We measured that.

• 31:24Speaker 12

  So you claim.

• 31:26Speaker 11

  Yes.

• 31:27Speaker 12

  Did you measure it with like one of those rulers you get at Staples?

• 31:31Speaker 11

  Yes.

• 31:32Speaker 12

  And then at the end, they put a ruler.

• 31:36Speaker 12

  The little wooden ruler.

• 31:38Speaker 09

  No, it's more like one of the wheels that you use to measure like more like the street.

• 31:43Speaker 11

  No, we measured that using the travel time of the laser. That's why the laser is so important.

• 31:48Neil deGrasse Tyson?

  Okay, but you have two facilities.

• 31:49Speaker 11

  Yeah, so, so, so why? Because this effect is so small. Now, we're trying to measure these tiny motions of mirrors and everything on our planet wants to move those mirrors by more than this passing gravitational wave.

• 32:00Neil deGrasse Tyson?

  I remember when I visited one of the facilities, you come near the, the beam, it says, "Drive really slowly towards the facility." Because anything is going to jiggle, shake and bake your experiment.

• 32:11Speaker 11

  And so that's.

• 32:11Neil deGrasse Tyson?

  So how do you know you didn't detect me driving into the facility?

• 32:14Speaker 11

  That's why we have two, because there's not two of you at, you know, 3,000 kilometers apart. By, by the same time.

• 32:20Neil deGrasse Tyson?

  How do you know?

• 32:22Speaker 09

  Or how do you know that there isn't another car with another person?

• 32:25Speaker 11

  So, so the way that you know is that the, the detectors, the two observ, at the two observatories, are instrumented with all kinds of other instrumentation, like seismometers that would measure you going by. And so we take those, we can remove those events from our signals. And now what happens, so think about the black holes we did detect. What we saw was a signal that arrived in our Louisiana detector first, and then seven milliseconds later, that same set of wiggles and bumps, that same signal.

• 32:55Neil deGrasse Tyson?

  So seven thousandths of a second.

• 32:56Speaker 11

  Yes, seven thousandths of a second later, it arrives at our Washington detector. And that told us something very important. It told us that the wave was coming in from the south, traveled through the Louisiana detector, and then continued on its way and seven milliseconds later, which is about the light travel time, this, you know, these waves also go at the speed of light, and it registered in the, in the Washington detector.

• 33:18Neil deGrasse Tyson?

  So it's not like a thing moving through the air. It is the rippling of the fabric of spacetime, shaking and baking Earth, being felt by one detector seven milliseconds after the other.

• 33:27Speaker 11

  Yes, that was, that was what it was. And that's what those two detectors are for.

• 33:35Speaker 12

  When, when you turned on the machine and you heard the signal, and, and you were like, "That's the real signal", did you guys then have a party?

• 33:45Speaker 11

  Yeah, so when, you know, in part because of the history of false starts in the field, many of us also have the psychology of, oh, no, that can't be real. So we looked at this beautiful signal and we were trying to talk ourselves out of it. But eventually, after we did enough testing, it was real. And then, yes, we did have a party.

• 34:04Neil deGrasse Tyson?

  You realized it wasn't me driving down the street?

• 34:06Speaker 11

  That's right.

• 34:06Speaker 12

  Did everyone get drunk at the party? But, but, um...

• 34:10Speaker 09

  Did you all have to come home drunk and go like, no reason?

• 34:16Neil deGrasse Tyson?

  Because the discovery paper has a thousand people on it. How are a thousand people gonna keep a secret?

• 34:20Speaker 12

  Huge party.

• 34:21Speaker 11

  They, we did pretty well, not perfectly, but pretty well.

• 34:24Neil deGrasse Tyson?

  You did damn well. I'm there and they're all just smiling ear to ear and nobody told me a damn thing.

• 34:52Neil deGrasse Tyson?

  Welcome back to StarTalk. Today, we're reaching back into the season seven archives to listen to some of your favorite moments according to your votes. One of your favorite conversations this season was with the principal investigator of the New Horizons mission to Pluto, Alan Stern, a longtime friend and colleague. In fact, I knew him back when, I mean, when he was a graduate student at the University of Texas. He thinks Pluto should be a planet. And well, you wouldn't know what I think about that. So this episode, we chat about the demotion of everyone's favorite ex-planet, Pluto, and what the New Horizons mission has unveiled. I'm joined in studio by co-host Chuck Nice and planetary scientist David Grin spoon. Both voted among your favorite StarTalk guests.

• 35:39Neil deGrasse Tyson?

  Other than Pluto's surface, as an object, has it changed anybody's notions of things dynamically? It's a thing orbiting the sun.

• 35:48Speaker 13

  Well, with the exception of Neil Tyson, it's convinced most people that it's a planet.

• 35:52Neil deGrasse Tyson?

  Okay, I'm pummeling him now. I'm giving him a niki on a thing.

• 35:55Speaker 13

  And then when people find out that if you drove around the circumference of Pluto, it's as far as from Manhattan to Moscow, they say, "I didn't know it was that big."

• 36:02Neil deGrasse Tyson?

  Yeah, yeah, yeah. I would say, whether or not anyone calls it a planet, I think, I learned this word in the Carl Saganian universe, where we get to call it a world. And a world has a certain intimacy to it, a conversational intimacy, because it tells you that it's a place. Maybe we'll go visit it one day. It's interesting to think about and to explore. And maybe that's what matters here, is it a world? The moons of Jupiter are worlds.

• 36:30Speaker 13

  They're planets.

• 36:34Neil deGrasse Tyson?

  Alan Stern has planet on the brain.

• 36:35Speaker 13

  Yeah, well, you know, it's important. My field is called planetary science. So I think it's important that we, as practitioners, understand what the central objects in our field are. And where Pluto falls in that is secondary to just having a basic, logical, consistent understanding of what are planets. And there's two ways to go at it. You can go at it scientifically. And scientifically, the physical planet definition says that when objects are big enough to be round, by self-gravity.

• 37:04Neil deGrasse Tyson?

  Gravity shapes it.

• 37:05Speaker 13

  And they're not so big that their central temperature causes them to ignite infusion. Anything in between, which is from about a tenth of Pluto's size up to about 10 times Jupiter's mass, will be called a planet. It's very simple. Or you could use the Star Trek test. You know, when the viewfinder comes on, the public knows in about a half a second what they're orbiting. It's a spaceship, it's an asteroid, it's a comet or a planet. Pluto passes by either test. But really, it's really about we, as scientists, being able to order things into boxes so that we can categorize.

• 37:41Neil deGrasse Tyson?

  So it's our problem?

• 37:41Speaker 13

  In a logical way.

• 37:42Neil deGrasse Tyson?

  It's not Pluto's problem, it's our problem.

• 37:44Speaker 13

  Well, Pluto's an inanimate object.

• 37:47Neil deGrasse Tyson?

  Okay, but of course, whatever is your concern about the legitimacy of the vote, our community voted in 2006 for the new classification. I don't believe-

• 37:57Speaker 13

  Actually, not so. 4% of the International Astronomical Union was there. 4% voted. It was almost 50/50. And so about 2% voted each way, and it went the other way. On a vote made up of non-experts called astronomers, not planetary scientists, I'd like to redo that vote-

• 38:15Neil deGrasse Tyson?

  Okay, so now-

• 38:16Speaker 13

  And really get the experts in-

• 38:17Neil deGrasse Tyson?

  But fine, what I'm saying is, I don't think anything I did had anything to do with that vote. So, and that's the vote that sets the language. So-

• 38:27Speaker 13

  But seven years ahead of that, running a very prominent exhibit at the American Museum of Natural History-

• 38:32Neil deGrasse Tyson?

  Yeah.

• 38:33Speaker 13

  You wanted to take Pluto and the small planets like it off the list of planets. Didn't you do that?

• 38:39Neil deGrasse Tyson?

  No, not really. No, we never had a list of planets. That's the thing. We never said Pluto wasn't a planet. We just grouped it with the Kuiper Belt.

• 38:47Speaker 13

  So if I go over to AMH today, I won't find any numbers like 8?

• 38:51Neil deGrasse Tyson?

  Never. There was never the number 8. I was misunderstood.

• 38:55Speaker 13

  I'm having the best time.

• 38:57Neil deGrasse Tyson?

  The press misunderstood me. And my team, who did this.

• 39:01Speaker 13

  So Pluto's a planet?

• 39:03Neil deGrasse Tyson?

  So, no, we did, the institution did not commit to whether-

• 39:06Speaker 13

  I'm asking Neil.

• 39:09Neil deGrasse Tyson?

  I think-

• 39:10Speaker 13

  This is where you get to make some news, Neil.

• 39:11Neil deGrasse Tyson?

  I think the disservice, let me at least meet you halfway. I think if dwarf planet is a category of planet, I have no problem with that. What happened was, people thought the dwarf planet meant it's not a planet anymore. And I agree, and that's where I can meet you somewhere-

• 39:27Speaker 13

  Good. So I like that. Dwarf planet is a category planet, just like dwarf stars. The sun is a dwarf star. Would anybody deny it's a star?

• 39:35Neil deGrasse Tyson?

  Yeah, it's a dwarf. Most people don't know it's a dwarf star, but it's a dwarf.

• 39:37Speaker 13

  It's true. Yeah. Yeah. That's pretty good, Neil.

• 39:39Neil deGrasse Tyson?

  Oh, we're shaking hands. Uh-oh.

• 39:41Speaker 13

  On camera. Because Neil just said dwarf planets are planets.

• 39:46Neil deGrasse Tyson?

  We can edit that out. You guys edit that out later.

• 39:48Speaker 13

  You probably will.

• 39:52Neil deGrasse Tyson?

  Guys, I told you to edit that out. Why is it still in there?

• 39:54Speaker 14

  Oh my god. Let me just say, that is a deeply wounded man you're talking to right there. I mean, he is, he just went Taylor Swift on you. He was just like, "We are never getting back together, Neil, never." "It's a planet, damn it, it's a planet."

• 40:11Neil deGrasse Tyson?

  So David, what's your take on all this?

• 40:13Speaker 15

  Well, you know, you heard me earlier in this conversation, use the word planet, and that's almost my reflex. Like, I wasn't trying to be provocative or make a point then. It's honestly how I think of it. And I do understand how people that are concerned with thinking about orbits and classification of gravitational influence, you know, might put dwarf planets like Pluto in sort of their own category. But as a planetary scientist, you know, I go to meetings where we talk about planetary geology and processes of planetary atmospheres. And when we're doing that and we're doing comparative planetology, we do use the word planet often when we talk about Pluto. We're saying, "Well, you know, this planet has a crater population

• 40:58Speaker 15

  that shows that this area is young." And people don't stand up and go, "Wait." You know, they correct and go, "No, you mean dwarf planet."

• 41:03Speaker 14

  That's because they've all been brainwashed.

• 41:08Neil deGrasse Tyson?

  Another one of your favorite episodes discusses the physics and fantasy of time travel. Professor Michio Kaku, a longtime friend and colleague, and co-host Chuck Nice, join me under the Hayden Sphere of the Hayden Planetarium to help us grasp the concepts. This show featured my interview with Back to the Future actor Christopher Lloyd, The Doc, and Doctor Who star Michelle Gomez, both of whom portray well-loved time-traveling characters in pop culture. Does the prospect of time travel intrigue you?

• 41:42Speaker 16

  Yes, absolutely.

• 41:43Neil deGrasse Tyson?

  How long, your whole life?

• 41:44Speaker 16

  From the moment I think my first thought would have been obsessed about

• 41:47Neil deGrasse Tyson?

  Really?

• 41:48Speaker 16

  being somewhere else. And it's only until now that I'm starting to realize that right here, right now, in this moment, right in this moment, everything's just fine and perfect.

• 42:00Speaker 16

  But that's taken me a few years to get there.

• 42:02Neil deGrasse Tyson?

  So your timeline was a work in progress until this moment?

• 42:07Speaker 16

  Yes, because it had to be beaten into me, into submission. My very sort of humanness has had to be beaten into me throughout the years.

• 42:17Neil deGrasse Tyson?

  Well, it's true for anyone. We are the sum of everything we've experienced.

• 42:20Speaker 16

  Yes.

• 42:20Neil deGrasse Tyson?

  Right, but not everyone puts it together.

• 42:23Speaker 16

  No.

• 42:24Neil deGrasse Tyson?

  Into a new entity.

• 42:25Speaker 16

  Consciousness.

• 42:26Neil deGrasse Tyson?

  A new consciousness.

• 42:27Speaker 16

  Yeah.

• 42:29Neil deGrasse Tyson?

  A new consciousness. Wow, man, you guys got really philosophical. Well, I'm just saying, you know, if you gotta go there, you gotta go there. A moment requires it of you. Yeah. So, Misha, what is this? If there's time travel, what does that say about free will?

• 42:42Speaker 17

  It means perhaps there's no such thing as free will.

• 42:46Neil deGrasse Tyson?

  No one wants to believe that.

• 42:47Speaker 17

  Right, however, you know.

• 42:49Neil deGrasse Tyson?

  I do, my life is a wreck.

• 42:52Speaker 17

  I'm a quantum physicist, and in quantum mechanics, there is uncertainty. And uncertainty means that we're not robots.

• 42:59Neil deGrasse Tyson?

  By the way, this is not uncertainty the way we normally use that word.

• 43:04Speaker 17

  This is the uncertainty in position and velocity of electrons. But since we are made of electrons, it means that there's uncertainty with regards to who we are. We exist in multiple states at the same time. And in some sense, you can be two places at the same time. So for us quantum physicists, having multiple universes is commonplace.

• 43:25Neil deGrasse Tyson?

  If you're gonna give yourself multiple universes, then I do have free will. There's a universe where some happen, I say, I don't wanna do that, I don't want that to happen. Let me go change that, and then I birth another universe where I can do something different.

• 43:37Speaker 17

  That's right. If there is uncertainty, then there are parallel universes, different time streams. And that resolves all the paradoxes of time travel. And it means that free will can exist because the timeline can fork into many roads.

• 43:55Speaker 14

  So each one of those timelines actually represents a different reaction to a choice. If you were this person, so I get up and I went one way to work as opposed to another way to work. I've created a different.

• 44:10Neil deGrasse Tyson?

  Multiverse by doing that?

• 44:11Speaker 17

  We create multiple universes simply by making decisions. Whether we wake up in the morning or sleep another hour in bed. Uh, we bifurcate, we split in half. And so for us, the time travel paradoxes are very easy to to resolve. Because we work with parallel universes every time we work with a transistor. The the internet, the internet is based on parallel universes. And some people don't like it, but hey, get used to it.

• 44:37Neil deGrasse Tyson?

  Still, Michio, I think you're invoking parallel universes to make everything you say work out okay.

• 44:45Speaker 17

  Hey, I think he's got it.

• 44:48Speaker 17

  That's exactly right. We believe in a unification of all physical law. And we think that quantum mechanics is the framework that even unites Einstein's theory to relative, to quantum mechanics. And the highest version of quantum mechanics is string theory.

• 45:05Neil deGrasse Tyson?

  So I worry that you know you can make another universe rather than commit yourself to this one and make it better.

• 45:12Speaker 17

  Oh, can I dodge that question?

• 45:16Neil deGrasse Tyson?

  Alright, so before we bring this to a close, you know we can't do it without like a video visit from Ni Times in the city.

• 45:23Speaker 17

  Yes.

• 45:24Neil deGrasse Tyson?

  Bill and I, the science guy, good friend and buddy. And now, you know, he's a resident of New York now. I finally got him to live here.

• 45:29Speaker 17

  You finally got him here.

• 45:30Neil deGrasse Tyson?

  Now he runs around town doing cool stuff and I'm still here stuck in this chair. So I'm told he got his hands on an actual DeLorean that was used in the movie. Let's check this out.

• 45:51Speaker 18

  Is time travel possible?

• 45:54Speaker 18

  No, probably not. Be cool though. You could go back in time and change history. Maybe you could go back to the Titanic and convince the captain to slow down. Or maybe just go back to last weekend and stop yourself from having one more tequila shot. Or maybe you could send a colleague back in time to have sex with a waitress who turns out to be your own mother. Like in the Terminator series. You know, to to prevent worldwide nuclear war. That'd be cool.

• 46:31Speaker 18

  Science fiction is replete with time travel stories. But I think for Neil and me, our favorite's gotta be the Back to the Future series. That's where Doc Brown turns a DeLorean sports car into a time machine.

• 46:47Speaker 18

  What if you could travel through time?

• 46:59Speaker 18

  Great Scott!

• 47:02Speaker 18

  Suppose everything, everyone you know and love, were actually part of someone else's time travel adventure? That would mean that you and I don't even exist. And as I finish this "Nigh in the City" segment, everything would just... disappear.

• 47:25Speaker 18

  That would be weird.

• 47:32Neil deGrasse Tyson?

  You've been listening to StarTalk Radio, and I'm Neil deGrasse Tyson, your host and your personal astrophysicist. Join us next time for Part Two of our Time Capsule Show, where we relive your favorite cosmic query moments of our seventh season. That's all for now, and as always, I bid you to keep looking up.