Things You Thought You Knew – Quantum Cat

What happens when you fall into a black hole? Neil deGrasse Tyson and Chuck Nice give us the step-by-step on spaghettification, explain Schrodinger's cat, and explore quantum tunnelling… Or do they?

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

• 0:00Neil deGrasse Tyson?

  Coming up on StarTalk, it's another Things You Thought You Knew episode. This time, we bring to you a few fan favorites. Death by Black Hole, Schrodinger's Cat, and Quantum Tunneling. Don't want to miss it.

• 0:19Neil deGrasse Tyson?

  Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now.

• 0:33Neil deGrasse Tyson?

  I want to describe what it's like to die as you fall into a black hole.

• 0:39Chuck Nice?

  Now, we were counting a personal experience here. Perhaps that could be the reason for the delay in discussing this.

• 0:48Chuck Nice?

  Are you sure you're ready for this? After this, after this harrowing experience.

• 0:53Neil deGrasse Tyson?

  One of the highest compliments I ever got was, I was giving a tour of the newly-built Hayden Planetarium, newly renovated, to Seinfeld, okay? Who, who lived across the street, so he was a neighbor.

• 1:05Chuck Nice?

  What's the deal with the lights?

• 1:07Neil deGrasse Tyson?

  Well, so I described the big bang to him in the first few moments and

• 1:11Chuck Nice?

  Right.

• 1:12Neil deGrasse Tyson?

  in exquisite detail, and he says, "It sounds like you were there." I thought, man, that's a high compliment. I, I, I'd never forget that.

• 1:23Chuck Nice?

  That's pretty funny.

• 1:24Neil deGrasse Tyson?

  I'm about to describe Death by Black Hole, and no, I will alert you in advance, I was not there.

• 1:30Chuck Nice?

  Okay.

• 1:31Neil deGrasse Tyson?

  But we know the physics of it, and that, that's just as good.

• 1:35Chuck Nice?

  All right.

• 1:36Neil deGrasse Tyson?

  So, a black hole, so you're standing here on Earth.

• 1:40Chuck Nice?

  All right, I am, by the way, sitting.

• 1:42Neil deGrasse Tyson?

  You're, you're sitting on Earth, and your feet are closer to the center of the Earth than the top of your head is.

• 1:51Chuck Nice?

  Okay.

• 1:53Neil deGrasse Tyson?

  Do we agree?

• 1:54Chuck Nice?

  I will agree, I'm not that short, so yeah.

• 1:57Neil deGrasse Tyson?

  You have to be really short for that not to be true. Gotta be kinda like a Mr. Potato Head.

• 2:04Chuck Nice?

  Just have your feet right at the bottom.

• 2:06Neil deGrasse Tyson?

  Of your head.

• 2:08Chuck Nice?

  Right up under your, right up under your neck.

• 2:11Neil deGrasse Tyson?

  I guess Mr. Potato Head didn't have a torso.

• 2:13Chuck Nice?

  No.

• 2:14Neil deGrasse Tyson?

  Oh, my gosh.

• 2:14Chuck Nice?

  That's right.

• 2:15Neil deGrasse Tyson?

  Oh, that is, that is sad.

• 2:18Chuck Nice?

  Yeah, it is.

• 2:18Neil deGrasse Tyson?

  Well, how come I never noticed that?

• 2:20Chuck Nice?

  Mr. Potato Head was all head.

• 2:22Neil deGrasse Tyson?

  It was all head and feet.

• 2:24Chuck Nice?

  Arms and feet. That was it.

• 2:26Neil deGrasse Tyson?

  Arms coming out of the side of his head.

• 2:28Chuck Nice?

  That's right. Arms, right.

• 2:30Neil deGrasse Tyson?

  All right. So you can calculate the strength of Earth's gravity at your feet. And the strength of Earth's gravity at the top of your head, and you'll get a different number.

• 2:42Chuck Nice?

  Wow.

• 2:44Neil deGrasse Tyson?

  Because your feet are closer to the center of the Earth.

• 2:47Chuck Nice?

  Okay.

• 2:48Neil deGrasse Tyson?

  And the closer you are to an object with gravity, the higher is the gravitational force operating on you.

• 2:56Chuck Nice?

  Okay.

• 2:56Neil deGrasse Tyson?

  So if I do that for you, you're five nine, something like that, what tall are you? And so you're five ten.

• 3:03Chuck Nice?

  I want that extra inch. You're a big guy, so you don't care. You're like six three, so you don't give a damn.

• 3:08Neil deGrasse Tyson?

  No, I'm six two.

• 3:10Chuck Nice?

  See, that's what I'm saying, you know? I gave you an inch.

• 3:14Neil deGrasse Tyson?

  I was six two in high school. I probably, you know, got the old man shrinkage from that. So, all right. So I can write down the difference between those two forces, and it's not going to be very much. So you don't, you don't think about it, you don't care about it. It's not much because your height is small compared with the radius of the Earth.

• 3:37Chuck Nice?

  Correct.

• 3:38Neil deGrasse Tyson?

  Radius of it's four thousand miles, and here you are, you know, just under six feet. So that's, so we don't think about this difference in the gravitational force. We don't have occasion to think about it. But that difference in force has a word.

• 3:56Neil deGrasse Tyson?

  It's called the tidal force.

• 3:58Chuck Nice?

  Okay.

• 4:00Neil deGrasse Tyson?

  Okay, now, the tidal force of the moon operating on the Earth. The side of the Earth facing the moon feels a stronger gravitational force of the moon than the side of the Earth that's on the, than the other side of the Earth that's farther away from the moon. You can calculate this, okay? And so the entire Earth is stretched in the direction of the moon.

• 4:29Neil deGrasse Tyson?

  Because of this tidal force.

• 4:31Chuck Nice?

  Okay.

• 4:32Neil deGrasse Tyson?

  The solid earth is stretched, but that's less notable noticeable because we're walking around on the solid earth. But what's most noticeable is the oceans are stretched. And it's called a tidal bulge. Alright, and so wherever you're gonna find the moon, you're gonna find a tidal bulge elongated pointing to the moon.

• 4:55Neil deGrasse Tyson?

  It actually doesn't point, it points ahead of the moon because we're dragging it in our, as earth rotates, but that's a whole other explainer.

• 5:02Chuck Nice?

  Okay.

• 5:02Neil deGrasse Tyson?

  Get into. For now, just consider it, we're aligned with the moon. Okay, so now watch.

• 5:08Neil deGrasse Tyson?

  That's because earth is big compared to the distance between the moon and the earth. Okay, so that's why, it's, earth is bigger compared to that distance that you are compared to earth radius.

• 5:18Chuck Nice?

  Right.

• 5:19Neil deGrasse Tyson?

  So now, watch what happens. Let's go, let's turn earth into a black hole. Let's just do that.

• 5:24Chuck Nice?

  Okay.

• 5:25Neil deGrasse Tyson?

  You know how you do that? You just shrink it.

• 5:27Chuck Nice?

  Okay.

• 5:29Neil deGrasse Tyson?

  Yeah, as you shrink it, the gravity on the surface goes up. Why? You're getting closer to the center of the earth and it still has all the mass in this model that I'm describing. Okay, two things tell you how much you weigh, how far away you are.

• 5:47Chuck Nice?

  Mm hmm.

• 5:48Neil deGrasse Tyson?

  And how much mass is tugging on you.

• 5:50Chuck Nice?

  Right.

• 5:50Neil deGrasse Tyson?

  As that happens, your size, which is still five feet ten.

• 5:56Chuck Nice?

  Right.

• 5:58Neil deGrasse Tyson?

  Relative to the size that the earth is becoming, is actually more and more significant.

• 6:05Chuck Nice?

  Right. Because the earth is no longer four thousand miles in radius. It's, that radius is shrinking and shrinking and shrinking, so it's becoming much closer to my size as it's.

• 6:20Neil deGrasse Tyson?

  Correct, correct, and when you do the math, the difference in the force between your feet and the top of the head gets greater and greater and greater.

• 6:30Chuck Nice?

  Oh.

• 6:31Neil deGrasse Tyson?

  Okay, so now, let's fall into a black hole and describe what happens. Okay?

• 6:40Chuck Nice?

  Okay.

• 6:41Neil deGrasse Tyson?

  So here you are, falling into a black, towards a black hole.

• 6:45Chuck Nice?

  Ah.

• 6:46Neil deGrasse Tyson?

  It, it, there's no air, so no one's hearing you.

• 6:49Chuck Nice?

  Damn it.

• 6:50Neil deGrasse Tyson?

  Okay.

• 6:53Neil deGrasse Tyson?

  You're just catching flies with your open mouth there, that's all.

• 6:58Neil deGrasse Tyson?

  So meteor particles. So you're falling feet first, let's give you a feet first dive. And the tidal force is slowly getting greater and greater. And initially, it feels kinda good. Who doesn't love a good stretch? Right?

• 7:17Chuck Nice?

  Best spa ever.

• 7:18Neil deGrasse Tyson?

  I know. And then you realize, wait a minute, that stretch is not only not abating, it's getting worse.

• 7:24Chuck Nice?

  Uh oh, we're getting medieval.

• 7:26Neil deGrasse Tyson?

  Yeah, exactly.

• 7:27Chuck Nice?

  We're getting medieval, this ain't cool.

• 7:30Neil deGrasse Tyson?

  Don't make me get medieval on your ass.

• 7:35Neil deGrasse Tyson?

  I had not thought about how medieval this is. Cause you look at the machines they had, it's like, what were they thinking?

• 7:43Chuck Nice?

  Let me tell you, somebody was staying up at night.

• 7:47Neil deGrasse Tyson?

  Thinking this stuff up.

• 7:48Chuck Nice?

  Ways to torture and kill people, cause.

• 7:52Neil deGrasse Tyson?

  That is effed up.

• 7:54Chuck Nice?

  Yeah, they excelled beyond, you know, imagination.

• 7:58Neil deGrasse Tyson?

  I heard there's another one where they disembowel you, and so that hurts enough. And then they take your intestines out and put it on the fire. So that you're not only in pain from being cut open, your organs are in pain. After they've removed it, because it's still, you know, your intestines are all stringy, right? So they're still connected to you. And so, and then you know what being drawn and quartered is? You know what that is?

• 8:24Chuck Nice?

  Um, is that the one where they put you on the horse, the four horses?

• 8:28Neil deGrasse Tyson?

  Yeah, four horses, right. So, so a horse to each limb. And then they give, they'll score you, right? They'll just, just so that you you cut more easily.

• 8:39Chuck Nice?

  Oh man.

• 8:42Chuck Nice?

  We must perforate him now. Wait for the perforation.

• 8:49Neil deGrasse Tyson?

  So you do that, and when the four horses run away, you are in four different pieces.

• 8:53Chuck Nice?

  That is disgusting.

• 8:55Neil deGrasse Tyson?

  No matter what, you are in four different pieces by the time that's done.

• 8:59Chuck Nice?

  Well, really, five, because there's a torso laying on the ground.

• 9:03Neil deGrasse Tyson?

  No, no, no, no. No, that's not how it works.

• 9:05Chuck Nice?

  No, I thought you, I thought you, so each limb.

• 9:10Neil deGrasse Tyson?

  Okay, so if I, if, so if three limbs are pulled off, the fourth limb is still attached to the rest of your body.

• 9:16Chuck Nice?

  No, I thought it was four, like four horses, one for each limb.

• 9:20Neil deGrasse Tyson?

  I know. What I'm saying is, your body doesn't rip apart simultaneously, okay?

• 9:26Chuck Nice?

  Oh, God.

• 9:27Neil deGrasse Tyson?

  Okay, so one horse rips off one arm.

• 9:30Chuck Nice?

  Oh, no!

• 9:31Neil deGrasse Tyson?

  And then one other leg, and then another leg, and one arm has slightly more muscle tissue there, holds on to the rest of the torso.

• 9:38Chuck Nice?

  I did not know this is how this thing worked. This is, I mean, you just made it ten times worse!

• 9:43Neil deGrasse Tyson?

  I'm saying that what you described, the limbs would have to be equally attached with a force, force tissue.

• 9:54Chuck Nice?

  Exactly.

• 9:55Neil deGrasse Tyson?

  Okay, equally, and simultaneously pulled in exactly the right angles.

• 9:59Chuck Nice?

  Exactly.

• 10:00Neil deGrasse Tyson?

  For them to pull off all at the same instant. And this is not how that works.

• 10:04Chuck Nice?

  I, that's my point. You ruined my fantasy is what I'm trying to say.

• 10:07Neil deGrasse Tyson?

  Okay, sorry, that you just dropped down in the middle as your four limbs.

• 10:10Chuck Nice?

  I just drop in the middle and I'm sitting there like an oblong, you know?

• 10:13Neil deGrasse Tyson?

  Then you're not being quartered, you're being dismembered. That's different.

• 10:16Chuck Nice?

  You're right.

• 10:17Neil deGrasse Tyson?

  Okay, so this is all a nice preamble for what's about to happen to you.

• 10:20Chuck Nice?

  Uh-oh.

• 10:21Neil deGrasse Tyson?

  Okay, so, your feet first falling towards the black hole.

• 10:24Chuck Nice?

  Okay.

• 10:25Neil deGrasse Tyson?

  The stretch feels good, but then it becomes unrelenting. Because your height is now a bigger and bigger fraction of the distance you are to the center of the black hole. All right, so now, you start sliding it, and what happens? Oh my gosh, the tidal force exceed, there will be a point where the tidal force exceeds.

• 10:51Neil deGrasse Tyson?

  The molecular forces that keep your body attached as one piece. Oh no, my molecular bonds! Your molecular bond, so you will snap into two parts. That's nasty. And I, and since all the forces are operating uniformly across your body, it's not like a horse yanking on one thing or another. I, I did a calculation, I have to, I probably have to speak with some physiologist about this, but I think you'll initially snap at your lower spine. Okay? So those are the two bits. Now, these, those two parts of you continue to feel the tidal force. Okay. So they stretch. Okay?

• 11:32Neil deGrasse Tyson?

  And so, your bottom half snaps into two pieces. Oh, right. Your upper torso snaps into two pieces, and as best as I can judge, that would be at the base of your neck. Okay?

• 11:46Neil deGrasse Tyson?

  Now, your brain is still working, you can in principle see this, okay? This happens pretty fast. And, by the way, they did these experiments, uh, from what I've read, in, um, in the French Revolution, with the guillotine. Right? If you're gonna be guillotine, you might as well help out science, right? So, with your head on the ground, before your brain really knows that it can't get oxygen from blood, do your eyes still work? Okay? And so, I think they did experiments where they hold up one finger, two finger, and you blink if you saw two fingers or one finger. Just for that, like, because your eyes go straight to your brain. They don't need your, your torso for, for none of that, okay? So...

• 12:32Neil deGrasse Tyson?

  People were messed up in the past, okay? Human beings are awful. It's not like a set up. Alright, so now you're in four pieces, and they continue to feel the tidal force, and then you go from two to four to eight to sixteen to thirty-two to sixty-four, and this continues until you are a stream of atoms. Like a train of atoms pouring down to the singularity. And that's not the worst of it. Go ahead.

• 13:03Neil deGrasse Tyson?

  Okay, the fabric of space and time funnels, funnels and gets narrower and narrower because it ends up at a singularity.

• 13:18Chuck Nice?

  Oh, no.

• 13:19Neil deGrasse Tyson?

  So whatever horizontal volume you occupied, you become extruded through the fabric of space like toothpaste through a tube. This form of death has a name and it's called spaghettification.

• 13:39Chuck Nice?

  Okay, well, I mean, I can't believe something that horrific could have such a delicious name. How did this happen?

• 13:51Neil deGrasse Tyson?

  So I many years ago wrote a book called Death by Black Hole. And I thought the book would do well and the publisher looked kind of askance at me like, no, we don't think this is gonna do well. I said, dude, look at the title, come on now. And so they, they, they didn't print enough copies when it was first released and it sold out in a day.

• 14:14Chuck Nice?

  Wow.

• 14:15Neil deGrasse Tyson?

  And then the, the, this is before we had like Amazon and everything. But so when you sell off the shelves, there's nothing there to buy. And but in that week, it hit the bestseller list, but it became a minimum bestseller. Right? It hit number 15 for one week. That's a minimum bestseller, but it would have stayed there if there was more books available.

• 14:36Chuck Nice?

  More copies.

• 14:37Neil deGrasse Tyson?

  Yeah, so I lorded that over the publisher ever since. Um, but anyhow, Death by Black Hole, and I describe this, but also I want to share with you a poem that I composed about Death by Black Hole. May I?

• 14:50Chuck Nice?

  Yeah, please do.

• 14:51Neil deGrasse Tyson?

  Okay, I'm not a poet, so dare I call it a poem. I'll call it a rhyme. Okay?

• 14:56Chuck Nice?

  Alrighty.

• 14:58Neil deGrasse Tyson?

  Here it is.

• 14:59Chuck Nice?

  Okay.

• 15:00Neil deGrasse Tyson?

  In your feet first dive to this cosmic abyss, you will not survive because you will not miss. The tidal forces of gravity will create quite a calamity when you're stretched head to toe. Are you sure you want to go? Your body's atoms, you'll see them, will enter one by one. The singularity will eat them and you won't be having fun.

• 15:30Chuck Nice?

  That, I have to say, is the scariest Dr. Seuss book I have.

• 15:39Chuck Nice?

  Good night, Timmy.

• 15:43Neil deGrasse Tyson?

  Behave tomorrow.

• 16:01Speaker 02

  Hello, I'm Vicky Brook Allen, and I support StarTalk on Patreon. This is StarTalk with Nailed Grass Tyson.

• 16:20Chuck Nice?

  This is something you hear all the time, especially in jokes, believe it or not.

• 16:24Neil deGrasse Tyson?

  Really?

• 16:25Chuck Nice?

  Yeah, Schrodinger's cat.

• 16:28Neil deGrasse Tyson?

  Wait a minute, you have a quantum division of the joke department?

• 16:31Chuck Nice?

  Well, I don't think that the comedians know what Schrodinger's cat is, but it's such a,

• 16:38Chuck Nice?

  it's such a ubiquitous reference.

• 16:41Neil deGrasse Tyson?

  Yeah.

• 16:42Chuck Nice?

  They make reference to it a lot of times.

• 16:46Neil deGrasse Tyson?

  It's interculture, it's interpop culture.

• 16:47Chuck Nice?

  It has interculture. I don't know why they don't call it Schrodinger's dog.

• 16:52Neil deGrasse Tyson?

  Okay, all right, so, all right, so it dates back to Erwin Schrodinger. Who, Erwin, yes, and he was a physicist. They all won Nobel Prizes, all these people who contributed to our understanding of the quantum. And quantum mechanics is what it's officially called, but I like just calling it quantum physics because it's an entire branch of physics that deals with the small, small things in the universe.

• 17:20Chuck Nice?

  So you do sweat the small stuff?

• 17:22Neil deGrasse Tyson?

  Yes, you do.

• 17:24Chuck Nice?

  I see.

• 17:25Neil deGrasse Tyson?

  Precisely, precisely, and the Schrodinger's cat relates a little bit to what people have called the observer effect. Okay, where if you observe something, you change. So I can respond to both of those in the same in the same pop, if you allow me.

• 17:43Chuck Nice?

  Okay.

• 17:44Neil deGrasse Tyson?

  So let's do the observer effect for the moment. So it's unfortunate that somebody called it the observer effect because then new age folk and other people who are basically scientifically illiterate. We're thinking it's your consciousness that affects what you're observing. And oh my gosh, there's a consciousness field and they go running off in a, you know, off the cliff.

• 18:04Chuck Nice?

  See, what you don't understand is that like particles

• 18:09Chuck Nice?

  are totally alive. Okay. And the reason why there is a collective consciousness in the universe is because like all of these particles that are spinning, what they're actually doing is conducting thought and consciousness.

• 18:24Neil deGrasse Tyson?

  They're thinking, they're thinking.

• 18:25Chuck Nice?

  Thinking, man. Rocks think, trees think more than rocks.

• 18:31Neil deGrasse Tyson?

  Right. So let me, let me cut through all of that and simply say that you're sitting there and I can see you because in fact you're illuminated by if not sunlight through an open window, an uncurtained window, but artificial light within the room. All right. That light hits your face, bounces off your face, goes through the computing system and I see you. Okay. That light carries energy. Every photon of light that strikes your face carries energy. And then they, they, most of them reflect, others get absorbed. Actually, it depends on how dark your skin is. Skin is very dark, it'll absorb most of them.

• 19:10Chuck Nice?

  That's because, you know, photons, they want to be a part of this, baby.

• 19:17Neil deGrasse Tyson?

  Let me get some.

• 19:21Chuck Nice?

  I see where we're landing. Oh, we got, oh, we got some good chocolate.

• 19:30Neil deGrasse Tyson?

  Yes, just to be more precise about Chuck's excursion there. Darker skinned people absorb more sunlight than lighter skinned people and it's your albedo. It's a, it's the percentage of incident energy that you absorb relative to what you reflect. Very important calculation. For the earth because what earth absorbs drives our climate. Whereas what earth reflects back to space just goes back to space. From the sun and so glaciers reflect light, cloud tops reflect light, oceans reflect light, that sort of thing.

• 20:02Chuck Nice?

  So for climate change to solve it, we just need to get a bunch of white people in one place.

• 20:09Neil deGrasse Tyson?

  Just reflect the light to reduce.

• 20:12Chuck Nice?

  Do us a favor, guys. Sunbath, everybody just sunbathe right here.

• 20:17Neil deGrasse Tyson?

  Reflect out the sun.

• 20:21Chuck Nice?

  Okay, all right, I'm sorry. I had to do it, man. All right, don't write, don't write, don't write.

• 20:27Neil deGrasse Tyson?

  But it was good. That was, that was funny. That was a good one. Yeah, I mean, if you, if the earth is getting hot, you just, just increase its albedo to increase the reflectance of it. So, yeah. So instead of Chuck's solution, everyone could just wear white clothing and that would work even better.

• 20:46Chuck Nice?

  That's more inclusive. I'll give it. That's more inclusive.

• 20:52Neil deGrasse Tyson?

  The D E I, the authorities will, that's how you do that on the campus.

• 20:58Neil deGrasse Tyson?

  So, so here's the thing, if I made you tinier and tinier and tinier. So you're no longer a macroscopic human, you're a microscopic particle. There's a particle size below which, when you open the curtains and shine light on you, that light will hit you and pop you into another location.

• 21:19Chuck Nice?

  So I'm smaller than the photon?

• 21:22Neil deGrasse Tyson?

  Than what the, your, your, your capacity to move to a different state of existence that the energy that, that is required to make that happen, correct, is now the same as the energy of the light that's hitting you.

• 21:37Chuck Nice?

  Gotcha. So you hit me with.

• 21:40Neil deGrasse Tyson?

  In order to see, in order to see you.

• 21:43Chuck Nice?

  Right.

• 21:43Neil deGrasse Tyson?

  And then you pop somewhere else and I say, where'd you go?

• 21:46Chuck Nice?

  Right.

• 21:47Neil deGrasse Tyson?

  So you're doing.

• 21:47Chuck Nice?

  So am I there? Am I not there? Well, we'll never really know because you're hitting me with something that makes me not there once you're exposing me to it.

• 21:57Neil deGrasse Tyson?

  Correct. And since it happens on the moment you're exposed, not the moment I see you. Right. I will never know what you were doing. Exactly. Okay, if you're small enough for that light energy to to affect you in that way. So that's why we don't think about this in everyday life, because we're too big for light to pop us into other states of existence. Exactly. But particles, electrons, atoms, all of this, it happens all the time. And this was a very disturbing discovery in the 1920s. We're in the centennial decade of the discovery of quantum physics in the 1920s. Because you discover, I want to see what you're doing. Oh, my gosh, you're not going to let me see what you're doing.

• 22:38Neil deGrasse Tyson?

  Because the light I shine on you in order to see it is, so it's really, it's not so much an observer effect, it's a measurement effect. Exactly. Okay, get the human brain out. It's just a device to measure you. You can't know it. Okay. Right. So, so, let's get on to, so it has nothing to do with consciousness. So let's get on to Schrodinger's cat. By the way, it's from an era where people spoke lightly of doing bad things to cats. Okay. Oh, no, Peter. So, you know, yeah, Peter wasn't around. So, so I'm a little disturbed that they picked cats, right? They could have picked dogs, they could have picked worms. But cats are lovable and will fit in a box, right?

• 23:19Neil deGrasse Tyson?

  And so, because cat, house cats don't come as large as house dogs do. Just think that through. Right.

• 23:28Neil deGrasse Tyson?

  Can you imagine? Yeah, a box for a dog is called your living room. Right. So, here's what happens. You say to yourself, you put a cat in a box. And if the cat is a quantum cat with two states, states of existence, it's either dead or alive. While it's in the box, you have no idea which it is. And so the way we describe this in quantum physics, if you do the experiments, okay, so some percentage of the time, you open the box, the cat will be alive, others, the cat will be dead.

• 24:06Neil deGrasse Tyson?

  And so you, what we say is that the, the cat's existence is a superposition of being dead and being alive.

• 24:16Chuck Nice?

  I got you.

• 24:17Neil deGrasse Tyson?

  It's a superposition of those two states.

• 24:19Chuck Nice?

  Because it's in the box.

• 24:21Neil deGrasse Tyson?

  It's in the box and you're not looking at it.

• 24:22Chuck Nice?

  And you're not looking at it. And that's why the superposition exists.

• 24:26Neil deGrasse Tyson?

  Correct. And it's a quantum cat, not a macroscopic.

• 24:28Chuck Nice?

  It's not, it's not, it's not Maru, the internet cat that people love to see jump out of a box.

• 24:35Neil deGrasse Tyson?

  Okay, alright.

• 24:36Chuck Nice?

  It's a hypothetical quantum cat.

• 24:39Neil deGrasse Tyson?

  By the way, do you know cats on the internet took a steep rise the same year that Cats on Broadway closed?

• 24:47Chuck Nice?

  Really?

• 24:48Neil deGrasse Tyson?

  Yes. Check your data on that.

• 24:49Chuck Nice?

  That is a weird little.

• 24:51Neil deGrasse Tyson?

  So we need somebody, we need somebody to investigate that because where did those cats go is what?

• 24:58Neil deGrasse Tyson?

  So it was like 1990, you know, early internet, you know, and cats closes on Broadway. And so I think people needed their cat fix and it landed on the internet.

• 25:07Chuck Nice?

  Landed on the internet.

• 25:08Neil deGrasse Tyson?

  So here we go. Now the.

• 25:09Chuck Nice?

  Superposition.

• 25:10Neil deGrasse Tyson?

  The details of that experiment are more, are more intricate than, than what I'm describing to you. Because what they wanted was to have like a, uh, something that's radioactive that would decay. And then that would then trigger a, a gate that would open the box. You know, it's a little more Rube Goldbergian than what I'm describing. But just to be clear, if you don't look in the box, you do not know if the cat is alive or dead. So the Schrodinger's cat is, you're talking about something that you don't know about until you actually investigate it.

• 25:42Chuck Nice?

  It's the end of the movie Seven.

• 25:45Neil deGrasse Tyson?

  I didn't see that.

• 25:46Chuck Nice?

  That was a movie that came out many years ago with Morgan Freeman and the beautiful man, I forget his name. Oh God, he's, uh, he did 12 monkeys, he's done, uh, Thelma and Louise, what's his name? Brad Pitt.

• 25:59Neil deGrasse Tyson?

  Oh, Brad Pitt, of course.

• 26:00Chuck Nice?

  Brad Pitt. So Brad Pitt is stalking a serial killer who is looking, who is using the seven deadly sins to kill people. Long story short, the last murder, he puts the head of someone in the box.

• 26:20Chuck Nice?

  And Brad Pitt wants to know what's in the box. And Morgan Freeman says, don't look in the box. There's no reason for you to look in this box. And Brad Pitt goes, what's in the box? Cause he knows that it's his wife's head.

• 26:37Neil deGrasse Tyson?

  That is completely morbid. Like, what?

• 26:40Chuck Nice?

  I know, but it's perfect. It should be called Schrodinger's cat. It should be called Brad Pitt's wife's wife's head.

• 26:48Neil deGrasse Tyson?

  Chuck, that is the most morbid analogy to this example I have ever heard.

• 26:52Chuck Nice?

  Oh, oh, cause a dead cat is perfectly fine.

• 26:55Neil deGrasse Tyson?

  Oh, no, okay.

• 26:59Neil deGrasse Tyson?

  So this actually, in a way, applies to quantum computing, which you might have heard snippets about, or at least bits of headlines that are making the news. So if we think of regular computing is like a zeros and ones, bits, right? And all calculations are done in this way. Well, quantum computing, the, a bit, a quantum bit, otherwise known as a qubit, can be either a zero or a one, or anything in between.

• 27:31Chuck Nice?

  Okay.

• 27:31Neil deGrasse Tyson?

  It could be 80% one, 20% zero, 50 50, 80% zero, 20% one, or anything on that continuum. And so, so the qubit has more computational versatility than a regular bit that can only be either a zero or a one. And, and the, and the, when I say you can be anywhere between a zero or one, statistically, you can have that bit represent 80% ones, 20% zeros, 50, it can be any combination of those two in the service of the programming that you're introducing to the computer.

• 28:10Chuck Nice?

  Holy crap.

• 28:11Neil deGrasse Tyson?

  So all of that, Schrodinger's cat, your dead wife's head in a box.

• 28:16Chuck Nice?

  Right.

• 28:16Neil deGrasse Tyson?

  From this morbid movie that now I'm never gonna see.

• 28:22Neil deGrasse Tyson?

  You were so excited about it, too.

• 28:24Chuck Nice?

  Because it's so much better than Schrodinger's cat.

• 28:27Neil deGrasse Tyson?

  Okay.

• 28:28Chuck Nice?

  It actually represents something that is consequential that, you know, I mean, never mind, it doesn't really make a difference.

• 28:39Chuck Nice?

  It's, I mean, it doesn't make any difference when, once you're in the quantum. It doesn't make a difference, but it's just a much cooler reference.

• 28:45Neil deGrasse Tyson?

  Right, right, because it's not a quantum head.

• 28:47Chuck Nice?

  It's not a quantum head, so it doesn't make a difference. You know, once you're in the quantum, it's not a, it's not a cat. It's a quantum cat and it's not a head. It's a quantum head, so.

• 28:56Neil deGrasse Tyson?

  I see what you're saying. It was never really a cat to begin with.

• 28:59Chuck Nice?

  Right.

• 29:00Neil deGrasse Tyson?

  It was a fictional quantum cat. In the same way, it's a, it's a quantum head.

• 29:04Chuck Nice?

  Exactly.

• 29:05Neil deGrasse Tyson?

  Oh, the world according to Chuck.

• 29:14Chuck Nice?

  That's so funny. You're like Chuck, uh, go have another bowl and get back to me.

• 29:20Neil deGrasse Tyson?

  So Chuck, there it is. That's like, you know, Schrödinger's cat 101. He could have called it Schrödinger's coin. Is it heads or tails?

• 29:27Chuck Nice?

  Right.

• 29:27Neil deGrasse Tyson?

  Right?

• 29:27Chuck Nice?

  Exactly.

• 29:28Neil deGrasse Tyson?

  It's just, it is this, is the quantum state only have two possibilities?

• 29:32Chuck Nice?

  Right.

• 29:32Neil deGrasse Tyson?

  In that description. And so, once you open the box and, and thereby gain access to information that is otherwise hidden from any observer or any, uh, device that would make the measurement.

• 29:46Chuck Nice?

  Coin is actually the best representation since if it's a superposition, like we said, or like you said, like I said, right? Please. Look at me taking, look at me taking credit for quantum discoveries. However, that means it's always a probability.

• 30:05Neil deGrasse Tyson?

  Yeah, it'd be a probability, correct.

• 30:06Chuck Nice?

  It's always a probability. So that means quantum coin is actually, you came up with the best one. Why, why you gotta do that? Why you gotta best me? Oh, I come up with a head in the box.

• 30:17Chuck Nice?

  And then you still gotta, you still gotta outdo me. Really? Really, bro? Come on.

• 30:22Neil deGrasse Tyson?

  We can't leave our fans with a head in a box version of this. I'm sorry. And, and just to be clear, the, the quantum state doesn't have to be one or the other.

• 30:31Chuck Nice?

  Right.

• 30:32Neil deGrasse Tyson?

  It depends on the atom and all the circumstances, but it can be any number of different states that each have a probability of being true.

• 30:39Chuck Nice?

  Exactly.

• 30:40Neil deGrasse Tyson?

  And, and in fact, the wave function of the particle extends outside of the box.

• 30:49Chuck Nice?

  Oh.

• 30:49Neil deGrasse Tyson?

  So the probability drops rapidly across the border of the box, but it still exists in a little bit outside the box. So what's inside the box has a probability of spontaneously disappearing from inside the box and appearing outside the box. That's called tunneling. And it does that instantaneously, like faster than the speed of light. Another spooky freaky thing in quantum physics, and that relates in part to quantum entanglement, because you can have two different particles whose wave functions interact on a way that when you do something, the one particle, the other one knows about it instantly because their wave functions communicate. This is quantum 101. It's like the fun parts of quantum.

• 31:33Chuck Nice?

  That is a lot of fun.

• 31:34Neil deGrasse Tyson?

  We should do a lot of these about quantum physics. This was like an overview. I could spend a whole explainer on each one of these things, because this is the decade in the 1920s was a watershed decade in physics, where Hubble discovers that we that the Milky Way is not the only galaxy. There are other island universes, they were called. Andromeda is another galaxy containing 400 billion stars. And four years, three years later, in 1929, he discovers that the universe is expanding. And we apply Einstein's relativity to show that we've got possibly a big bang, which would later would make 50 years before we had the supporting data. And most of what we now know, understand and love about quantum

• 32:17Neil deGrasse Tyson?

  physics was discovered in the 1920s. And we knew all of that before the neutron was discovered.

• 32:24Chuck Nice?

  And before Texas Instruments actually made a calculator.

• 32:29Neil deGrasse Tyson?

  Uh, yeah.

• 32:35Neil deGrasse Tyson?

  And why is that?

• 32:38Chuck Nice?

  Because that means these guys had to work that math out on their own.

• 32:43Neil deGrasse Tyson?

  Okay, before anybody made a calculator. Right, right. Exactly. Exactly. By the way, I had a friend who had the very first Texas Instruments scientific calculator. And he knew it was the first because it didn't even have a model number on it. It predated model, it would ultimately become the TI 35. But we, I remember we all crowded around it staring at it. It was this, one of those moments that you never forget.

• 33:08Chuck Nice?

  Okay, I just love the visual of a bunch of nerds crowded around. And then, you know, you think they're looking at a magazine or something. And then you part the ways and they're all around a calculator like, whoa. Look at that. Can you believe this thing?

• 33:24Neil deGrasse Tyson?

  Welcome to the geek, the geekiverse.

• 33:26Chuck Nice?

  Do cosign, do the cosign again.

• 33:30Neil deGrasse Tyson?

  I'm a tangent man myself.

• 33:57Neil deGrasse Tyson?

  So if you're standing on one side of a hill.

• 34:03Chuck Nice?

  Okay.

• 34:03Neil deGrasse Tyson?

  And you've got to get to the other side of the hill. You, you're going to climb over the top of the hill and come down the other side.

• 34:10Chuck Nice?

  Yeah. Or, I mean, that's why I had children. They're going to pull me up over the hill.

• 34:14Neil deGrasse Tyson?

  Let them haul your ass.

• 34:16Chuck Nice?

  Do the work. I'm gonna sit right here in this little cart. Y'all get moving.

• 34:21Neil deGrasse Tyson?

  So another way to do it is to bore a hole through the mountain, through the hill and come out the other side.

• 34:29Chuck Nice?

  So true.

• 34:30Neil deGrasse Tyson?

  By doing so, you've made a tunnel.

• 34:32Chuck Nice?

  Correct.

• 34:33Neil deGrasse Tyson?

  Okay. So you've, you've, you've, you've made it easier to get from one side of the hill to the other. Because you don't have to go up and then come back down.

• 34:41Chuck Nice?

  As a person who lives in Jersey, I appreciate that concept.

• 34:44Neil deGrasse Tyson?

  The tunneling, the tunneling from in and out of Manhattan.

• 34:47Chuck Nice?

  That's right.

• 34:48Neil deGrasse Tyson?

  Correct. Okay. So, um, here's something interesting. In quantum physics, we can think of the hill as a, as an energy barrier to you.

• 35:03Neil deGrasse Tyson?

  Okay.

• 35:03Chuck Nice?

  Well, okay, that makes sense.

• 35:05Neil deGrasse Tyson?

  All right, so you need energy to ascend the hill. Otherwise, you'll just stay where you are. So now we check, how much energy do you have? Oh, I can get halfway up the hill, but not any further. Three quarters of the way, but not any further, okay? So, in quantum physics, if there's a hill, we call them potential barriers, because, all right, they're actual barriers, but they're called potential barriers. They, so there it is. You have a particle on one side of that barrier. And you give the particle energy, that can't make it, I can't make it.

• 35:38Chuck Nice?

  This hill is too much.

• 35:43Chuck Nice?

  Why you gotta? Let's just stay here. Why don't we just live here now?

• 35:50Neil deGrasse Tyson?

  You wiping the sweat off your brow like electron, like electron sweat.

• 35:55Chuck Nice?

  You have no idea how hot that nucleus.

• 36:01Neil deGrasse Tyson?

  So, so, what I have, so, the particle, however, is not only a particle, it's also a wave.

• 36:09Chuck Nice?

  Okay.

• 36:10Neil deGrasse Tyson?

  And when you're a wave, there's something called a wave function. And a wave function is the probability of finding it anywhere in a volume spanned by that wave function. Okay? So you're more likely to find it where the wave peaks and where the wave drops off, you're less and less likely to find it there. And there's a point where don't ever wait around because it won't show up for trillions of years, all right? So, but, there's an actual likelihood it can show up anywhere in the wave function, even in the low probability places. All right. So that wave doesn't know about and doesn't care about the mountain.

• 36:45Chuck Nice?

  Okay.

• 36:46Neil deGrasse Tyson?

  So you can ask, does some of that wave show up on the other side of the mountain?

• 36:55Neil deGrasse Tyson?

  If it does, then there is a probability that the particle that's stuck on one side will just simply appear on the other side of the mountain, having never had to ascend it in the first place, because it didn't have enough energy to do it. But because it exists as a wave function, there will always be a probability that it can show up where it was not invited.

• 37:23Chuck Nice?

  Oh.

• 37:24Neil deGrasse Tyson?

  That's called quantum mechanical tunneling.

• 37:27Chuck Nice?

  Quantum wedding crashing.

• 37:29Neil deGrasse Tyson?

  We built this wall.

• 37:33Chuck Nice?

  Did you see that potential barrier?

• 37:36Neil deGrasse Tyson?

  You should see that wall.

• 37:38Chuck Nice?

  Doesn't potential barriers mean anything to you?

• 37:40Neil deGrasse Tyson?

  This would be good for a Trump interview. They built the wall. But they're still tunneling in. They must be quantum mechanical entities.

• 37:53Chuck Nice?

  This is the thing. Why aren't these... Why aren't these quantum... From Norway? I'm sorry. Why can't we get the ones from Norway? They wouldn't have to tunnel. Okay.

• 38:17Neil deGrasse Tyson?

  So that's just quantum tunneling. So here's... So I'll show you how that manifests. Very interesting little history here. And then we'll call it quits, because this is just an explainer. In the early days, a hundred some years ago, we didn't know where you made... Where you got all the elements in the universe.

• 38:33Chuck Nice?

  Okay.

• 38:34Neil deGrasse Tyson?

  By the way, I remembered asking my high school chemistry teacher, where do the elements come from? He's, oh, they're in the earth. And I would later learn, no, we made these suckers and stars, dude. All right? Why don't you look up every now and then?

• 38:44Chuck Nice?

  That is so funny.

• 38:46Neil deGrasse Tyson?

  Okay. So it's not his fault. He's a chemistry teacher. He thinks of the elements...

• 38:51Chuck Nice?

  And we know how stupid they are.

• 38:52Neil deGrasse Tyson?

  No.

• 38:53Chuck Nice?

  Come on. Let's be honest. He's a chemistry teacher. He's no physicist. Come on. What do you want?

• 39:00Neil deGrasse Tyson?

  Check.

• 39:01Chuck Nice?

  What do you want?

• 39:02Neil deGrasse Tyson?

  So... So in the early days, the question was, where do we get these elements from? You could build them from smaller elements, alright? If you merge them. So they did the calculation of what it would take to merge two hydrogen atoms. Okay? Now, what's in the nucleus of a hydrogen atom? A proton. So you have a proton here and a proton there. And I want to merge them to make a nucleus that has two protons in it, which would be helium. That's a way to build elements from scratch.

• 39:35Chuck Nice?

  Okay.

• 39:36Neil deGrasse Tyson?

  So, a proton is what charge?

• 39:40Chuck Nice?

  Uh, wait, the proton is positive.

• 39:42Neil deGrasse Tyson?

  Positive. And the charge on the other proton?

• 39:45Chuck Nice?

  It's also positive.

• 39:46Neil deGrasse Tyson?

  It's also positive. Like charges?

• 39:49Chuck Nice?

  Oh, they don't really like each other.

• 39:50Neil deGrasse Tyson?

  They repel, okay? So you have to get them close enough so that the, a strong nuclear force kicks in and holds them together. Okay? That's the basic task you have to accomplish here.

• 40:08Chuck Nice?

  Sounds like Thanksgiving dinner at my crib.

• 40:10Neil deGrasse Tyson?

  To force it in.

• 40:12Chuck Nice?

  Right, get in there!

• 40:13Neil deGrasse Tyson?

  Get in there.

• 40:14Chuck Nice?

  Right.

• 40:15Neil deGrasse Tyson?

  So it turns out the electromagnetic repulsion, the two positive charges, you can sort of get them closer and closer if you speed them up by increasing the temperature of the plasma. They'll speed up, they'll get closer and closer and closer to each other as you increase the temperature. So you ask, at what temperature will they be close enough for the strong nuclear force to kick in and grab them? Okay?

• 40:40Chuck Nice?

  I don't, okay, that's the question.

• 40:42Neil deGrasse Tyson?

  Okay, that temperature is like a billion degrees.

• 40:44Chuck Nice?

  Well, there you have it.

• 40:46Neil deGrasse Tyson?

  A billion, and we look, and we do the calculation for the centers of stars, it's not a billion degrees.

• 40:51Chuck Nice?

  So I'm taking it that the building of the elements doesn't work by getting a billion degrees?

• 40:59Neil deGrasse Tyson?

  No, it would if you could.

• 41:00Chuck Nice?

  If you could, but I'm saying that, yeah.

• 41:02Neil deGrasse Tyson?

  Right, right. So, so the question was, so I think it was Eddington, a famous physicist of the day, astrophysicist, he was asked, he said, well, then where are we gonna get the elements? I don't know where, but if it's gonna happen anywhere, it's gonna be in the center of stars. Okay, so even though we couldn't give him a billion degrees. Right. He still said, I don't see any place else in the universe that will satisfy the needs of this requirement. Except the centers of stars. Okay, so they're just sat for decades. Okay, not many decades, but we just sat there as an unsolved problem. Until quantum physics came along. And then they said, okay, here's a proton coming close to another proton.

• 41:45Neil deGrasse Tyson?

  So there's a barrier there that it can't cross. But wait a minute, the particles are also waves. And part of that wave exists within the grasp of the strong nuclear force. Right. And so there's a probability that some of these particles will merge and make helium. Wow. So then you say, what is that probability? So, so they said, well, what is the temperature of the center of the star? They said 10 million degrees. It's not a billion. It's like 10, 15 million. So you do the math on the quantum physics and you say, what percentage of collisions?

• 42:25Neil deGrasse Tyson?

  Will, will tunnel through this barrier and end up making helium? You come up with that percent and bada bing, you recreate the total energy output of the sun. Look at that. So you're glad it's not converting every encounter into energy. Right. The sun would just boil. Well, yeah, yes, just like, why is everything, God damn is hot.

• 42:57Neil deGrasse Tyson?

  Says the, says the person who by then is just a puff of smoke. Exactly. You don't have time to utter those words. Right. Wow. Okay, that. All right, so. Fascinating, fascinating. So, so the thermonuclear fusion in stars that generates the energy at the temperatures it does. Can only happen because of quantum mechanical tunneling. That's.

• 43:23Chuck Nice?

  Boom, that is amazing!

• 43:25Neil deGrasse Tyson?

  And so just think about the challenges, you know, we astrophysicists have. We haven't, by the way, so Eddington was right, it does happen in the centers of stars.

• 43:34Chuck Nice?

  Of course.

• 43:34Neil deGrasse Tyson?

  Right, because nowhere else was rational, right? But we didn't know enough physics at the time it was proposed to answer that question. New physics had to be invented. And this is why we are always so excited when new physics comes along. There are people saying, people say, "Oh, someone has a new physics idea, but everyone else is rejecting it because they don't want to lose their highly invested lives in this." They're thinking that we don't like new ideas.

• 44:03Chuck Nice?

  They got to you, Neil!

• 44:06Neil deGrasse Tyson?

  We love new ideas. Because they give a whole new understanding on the frontier of stuff that we didn't previously understand.

• 44:14Chuck Nice?

  Right.

• 44:15Neil deGrasse Tyson?

  And so, yeah, that's quantum mechanical tunneling. Oh, oh, one other thing? It, no matter the size of that potential barrier.

• 44:25Chuck Nice?

  Right.

• 44:26Neil deGrasse Tyson?

  It tunnels and appears on the other side instantly.

• 44:29Chuck Nice?

  Oh, so, okay, so...

• 44:31Neil deGrasse Tyson?

  The wave function just collapses and it's there.

• 44:33Chuck Nice?

  Right.

• 44:34Neil deGrasse Tyson?

  It doesn't travel there, it was always there probabilistically, okay? So when your wave becomes the particle, boom, it is there.

• 44:44Chuck Nice?

  So then distance makes no, it's immaterial.

• 44:47Neil deGrasse Tyson?

  It's immaterial, it's instantaneous. So we think that it moved, but it really didn't, it was always there to begin with.

• 44:54Chuck Nice?

  That is so freaky.

• 44:56Neil deGrasse Tyson?

  Yes, freaky.

• 44:57Chuck Nice?

  That is so freaky.

• 44:58Neil deGrasse Tyson?

  Quantum physics is, that's only part of the freaky stuff.

• 45:01Chuck Nice?

  Yeah.

• 45:01Neil deGrasse Tyson?

  That's like the 12th freakiest thing I could tell you.

• 45:04Chuck Nice?

  Yeah.

• 45:04Neil deGrasse Tyson?

  Because you can't handle the other 11.

• 45:06Chuck Nice?

  I can't handle this!

• 45:10Neil deGrasse Tyson?

  You can't handle it, dude! Oh, there's another one, we'll save it for another one, to talk about a Bose-Einstein condensate.

• 45:18Chuck Nice?

  The Bose-Einstein condensate?

• 45:21Neil deGrasse Tyson?

  Yeah, let's save that for another explainer.

• 45:23Chuck Nice?

  Yeah, okay, cool.

• 45:24Neil deGrasse Tyson?

  That's a good one.

• 45:25Chuck Nice?

  Yeah.

• 45:25Neil deGrasse Tyson?

  That's a totally good one.

• 45:26Chuck Nice?

  That sounds delicious, like something else.

• 45:30Chuck Nice?

  You know, right. Tonight's special is a farm-raised Bose Einstein condensate. Um, with, uh, an arugula compote that, uh, we have, um, distilled down into a deconstructed, uh, quantum.

• 45:49Neil deGrasse Tyson?

  My boy's been to some restaurants lately. Get that fancy restaurant vocabulary going.

• 45:54Chuck Nice?

  That's pretty wild. The Bose Einstein condensate. All right, we'll do that later.

• 45:59Neil deGrasse Tyson?

  A little bit. A little bit relates to, not really, but it's, it's, it's another freaky, wacky quantum phenomenon that we'll say, we'll say for another time. We got it. All right, Chuck.

• 46:11Chuck Nice?

  That was, that was great.

• 46:13Neil deGrasse Tyson?

  Quantum tunneling.

• 46:14Chuck Nice?

  Quantum tunneling, baby.

• 46:16Neil deGrasse Tyson?

  Be there. All right. Neil deGrasse Tyson here with Chuck Nice. Four Star Talk.