How We_ll Get to Alpha-Centauri _ Cosmic Queries _115

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A lot of people think a five-year-old wouldn't know the
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ways of the world. I quit smoking two years ago. Hello,
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mi amor, mon ami. I would like very much to
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make love to your le grand point. A lot of
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people don't know, but nobody knows more about looking at
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the sun than I do. I can look at it.
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I stared it down and I won.
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Stared so hard at it, the sun set. Exactly.
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Oh that's a good one.
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This is StarTalk Cosmic Queries Potpourri Grab Bag Edition. Chuck,
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how you doing, man?
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Doing great, Neil. That's right.
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All right. I like the way you say potpourri. Let
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me hear it.
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The potpourri, which is my version of galactic gumbo.
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Yeah, we don't know what to call this other than
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grab bag. Grab bag seems to work.
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Yeah, grab bag works.
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And it's a fan favorite because people ask whatever the
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hell they want. Whatever you want. All right, Chuck, so
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what's your first question?
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All right, here we go. Trisha Lynch says, hello, Dr.
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Tyson and Lord Nice. This is Trisha from Beaverton, Oregon.
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If the multiverse exists, how will we be able to
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tell where our universe ends and another universe begins? Well,
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thank you.
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I like that.
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Interesting.
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I like that. Well, there's several variations on the multiverse.
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And I only know a couple of them, but they're
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more than the number that I know. And they come
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out of sort of the mathematics of the early universe
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as you shotgun marry quantum physics and general relativity with
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string theory and other sort of creative ideas in the
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early universe. So one version of the multiverse is... There's
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one enormous grid of space-time, and we're one bubble within
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that grid. Okay?
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Okay.
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The difference is these bubbles are separated from each other
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in a way that you cannot access the other bubble.
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At the end of our universe is wherever that is,
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but it would not overlap with another universe, even though
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all of these universes are expanding.
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If it's a bubble in the spherical sense of a bubble.
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Yeah, sure.
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Then the universe ends where the universe begins. Uh, like
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where is the end of a bubble? Where is the
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end of a bubble?
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So, so you might say that the, Edge of the
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bubble is where you begin your journey into the bubble universe. Exactly.
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Is that an end or a beginning? Yeah, that's a
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good point.
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Is that an end or a beginning, right? You know?
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I like that. I like that. Yeah. A legit reinterpretation
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of the information.
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Okay.
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So all of these universes are out there expanding and
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not overlapping. So that's a– by the way, on the
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possibility that they might have overlapped, there are experiments you
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can do. with the cosmic microwave background, what you can
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do is you can look to see if one part
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of the cosmic microwave background looks statistically different from another
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part of the cosmic microwave background in a different direction.
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And that could be somebody else's universe impinging on ours.
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And that would show up in the statistical analysis of
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the microwave background. And people have done that experiment and
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look for these signatures and haven't found them. They found, yeah,
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there's no, there's nobody impinging on our statistical, uh, uh,
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on the statistics of our universe. And I say statistics of,
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because the microwave background is, is a, is a tapestry
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of fluctuations of temperature that existed in the early universe
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that is imprinted in microwaves that we can observe today.
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And if there's a different universe, it might have a
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different imprinting. And you'll be able to see that. You
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should be able to see that if there was some overlap.
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And we don't. So that's one kind of multiverse. Another
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one is just a whole bubble separate from this grid
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of space-time that I presumably embedded in a higher dimension.
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And it's expanding and we're expanding and never the twain
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will meet. So- Plus, it's possible, in fact, it's likely,
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given quantum physics, that the laws of physics are slightly
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different in one universe relative to another. And that would
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be extremely dangerous if you wanted to visit the other universe.
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Because you don't know, is the charge on the electron different?
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Will all your atoms fly apart or will they collapse? Hey,
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look who showed up. It's the goo people. Where did
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these goo people come from? Did you collapse into a
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pile of goo because all the forces that otherwise kept
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you alive are doing something different? Right. Yeah. So that's
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the best I can address this. What I might do
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is next time we get Brian Green on, we can
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bring up that topic with him. See if he has
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any more to add to it because he knows he's
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more nuanced about elements of the multiverse that could influence
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or impact the full answer to that question.
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Cool. All right.
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Why don't you put a star next to that? Put
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a star next to that. And we'll hold it aside
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for when Brian Green shows up again. Flag it for
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Brian Green. Yeah.
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Super cool. All right, then let's move on to this
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is Mary Mitchell. And Mary says, hi, Dr. Tyson.
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Lord, nice.
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Mary from Oregon. Two Oregons in a row. Two Oregons
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in a row.
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I was just in Oregon just a few weeks ago.
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Okay.
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In Asheville, Oregon.
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Asheville? Oh, my God. That is a party town.
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Was it Asheville or Ashland?
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I don't know. Ashland. I don't know.
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Ashland Art. That's the site of the Oregon Shakespeare Festival.
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Oh, really?
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Yeah. Oh, I said it was a party town. It's
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quite the culture tenor.
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Exactly. Indeed. The Shakespeare.
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Ashland was in North Carolina. Ashland is in Oregon.
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Ashland is in Oregon. Okay. All right. Mary says this.
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The cosmic query is for both of you. Okay. What
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is one of your favorite words in astrophysics? Is there
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a particular word that reflects the structure function of of
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its referent or that it's just fun to say? Alternatively,
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is there a word in astrophysics that chafes your geeky underbelly?
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If so, what's your issue with it? Thanks.
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Okay. I love that question. And let me tell you why.
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My second book ever was titled Universe Down to Earth.
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Second book ever came out like in the early 90s.
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And in fact, I've been asked to update it and
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have it get re-released, which might happen in the next
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18 months or so. And I mentioned that because one
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of the chapters is titled The Confused Person's Guide to
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Astronomical Jargon. And so the entire chapter is just words
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that might confuse you. And then I rectify that. And
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the words are grouped in categories, like words that mean
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exactly what they say, words that are completely confusing, words
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that sound like romantic destinations, words. So they're grouped, they're
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socially and culturally grouped.
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Wait, you put this out as a book? Yeah.
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Well, that was one chapter of a book. Yeah.
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Dude, you should make a pocket book, like a little
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pocket book.
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Oh, okay.
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All right. By the way, I want to cut. I'm
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just saying y'all heard it here.
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So in terms of like romantic words, so I put
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it in the romantic word section. your Lagrangian point.
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Oh, yeah. Oh, yes. We have a whole explainer on
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your Lagrange points. Lagrange points, yes.
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But if you didn't otherwise know, that's going to show
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up in some romance book.
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Hello, mi amor, mon ami. I would like very much
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to make love to your Lagrange point. If only I
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could hold your Lagrange point. at the precipice, not only
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would you freeze.
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So what's also there is for telescopes that observe the sun,
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there's a special configuration of the optics where the focus
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of the telescope because the sun has unlimited brightness, right?
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Compared to what you're normally looking at as an astronomer.
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You look at it directly from the white house. A
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lot of people don't know, but nobody knows more about
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looking at the sun than I do. I can look
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at it. I stared it down and I won.
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Stare too hard at it. The sunset.
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Oh, that's a good one. I see. I stared at
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it so hard, it set. Yeah.
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So, what happens is you have the main mirror that
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reflects the light back to a secondary mirror and then
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you take that light and beam it into a separate
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room and all the optics are configured so that no
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matter where the sun is in the sky, the focus
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will land in this singular room and that room has
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all the special optics to do this and it's called
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the coude focus the coude was the is the uh
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um that's the description of that kind of optics but
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the room where it comes in is called the coude
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room so i just thought that that had a little romantic.
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It does have a flavor to it.
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Shall we retire to the coup d'etat room?
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Oh, dear.
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So I also list words that I hate that were
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not invented by astronomers because we're much more creative and
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descriptive than our physics counterparts. And so there's a branch
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of study led by physicists in astrophysics, and it's called magnetohydrodynamics.
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That's just a word with too many syllables. I'm sorry. Magnetohydrodynamics.
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And so this is the study of magnetic fields and
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their influence on gases in the universe, whether those gases
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be gas clouds or the gas constituents of a star itself. Magnetohydrodynamics.
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So then we have words that mean exactly what they say.
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Exactly what they say. The sun has spots. Guess what
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we call them?
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Sunspots.
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Thank you. Jupiter has a big red spot. Guess what
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we call it?
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Yeah.
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The Jupiter bedwetting. Yeah, the big red spot. Jupiter's red spot.
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And so we tend to be very practical-minded about that.
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And there are a lot of nebulae out there, just
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gas clouds formed by multiple different ways. Some are gases
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that have been released by a star in its death.
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Could be supernova, could be other mechanisms that will release gas.
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Others are just gas clouds themselves. that have been influenced
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by stars being born within them that evacuates pockets because
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of the pressure from newly formed sunlight. We'll do that. Anyhow,
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when we look at these things, we say, what does
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that look like? Hey, that looks like a tarantula. We
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have a tarantula nebula. Hey, that looks like a ring.
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That's a ring nebula. These are official names of things.
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You could look these up. The ring nebula, the tarantula nebula,
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the lagoon nebula, the owl nebula, something that looks like
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two eyes and the owl nebula, the eagle nebula that
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looks like a spread eagle, like on a, on money,
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you know, on a, on the seal of the president
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with the head of the eagle is pointing sideways. So
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you can see the eagle nebula. So the whole set
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of nebulae, we just call them like we see them.
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And yeah, And that's very different from other fields where
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they will try to be very precise in their nomenclature,
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but then it creates a smokescreen for anyone trying to
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get close to it. Like geologists, like, you know, I
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was with a geology friend in the woods and I said,
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that's a pretty rock there. That's orthoclase feldspar. Okay. I
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don't like your rock anymore.
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Exactly.
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That's, yeah. Yeah.
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Take it to Star Trek, buddy.
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Yeah, exactly. Exactly. So is there anything that chafes my,
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my speedos? I would say magnetohydrodynamics. Because as an educator,
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I don't want a smoke screen with words. I don't
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want the word to be the barrier. I want the
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idea to be what might be the challenging point about
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what I'm describing, not the word itself.
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Right, right.
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And so I don't know if I hit all the
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elements of that. Do you want to know what's my
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favorite word? No, you got it all. What shaped you?
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What did you like? Yeah, you hit them both.
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Yeah.
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Yeah. Here's a word that means exactly what it says.
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Thermonuclear fusion.
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Absolutely.
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Thermo is heat. Nuclear is the nucleus of the atom. Fusion,
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you're bringing atoms together.
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Together.
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Bada-bing.
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Yes.
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Nope, that's lame.
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Ready?
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Do you harbor questions about the universe? Some long-held bit
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of cosmic curiosity? lingering within you, or questions about anything
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at all, you can become a Patreon supporter of StarTalk.
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You have access to our exclusive question line on our website.
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Those are where we draw our questions for our cosmic learning.
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Some of the most extreme objects in the universe.
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StarTalk is a work in progress where we, every month,
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Come up with some new way, some new idea, some
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new understanding of how to bring the universe down to Earth.
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We could not do that without your support. Thank you.
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And as always, keep looking up. By the way, we
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have words that are left over from previous times, but
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we never tidied up the nomenclature. Among the nebula, there's
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a kind of nebula called planetary nebula.
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Planetary nebula.
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Oh, oh, that's sad. That's sad that it got called that.
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That's why it's not a thing.
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Okay, are you ready?
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Go ahead.
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You ready for this? Okay, okay. If you have a
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telescope and you look up at the night sky and
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you look at a star, the star is so far away,
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it's just a point of light even in a telescope.
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Even in a telescope.
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They're all just points of light even in a telescope, okay?
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Right.
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If you look at a planet... It's a disc. You
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can see a circular disc there. Obviously, it's a sphere, spherical.
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But to a telescope, you see a round thing.
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Okay?
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William Herschel, I think it was, found a nebula that
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was round. And he called it a planetary nebula because
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it looked planet-like through his telescope. Even though he knew
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it was a gaseous thing and he knew it wasn't
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a planet, he just was naming things just by what
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they look like, not for what they are. And so
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I'm pissed off that we still have that term for it.
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Yeah, Herschel, you dumbass.
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God. Well, the dude discovered other things. So you got to,
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you know, give him, he discovered infrared light.
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Right. That's true. I mean, listen, but that was, you know,
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that was him looking at a table. All right. Where,
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where he belonged looking. Okay.
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You also discovered Uranus. So.
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No, not my anus. Okay.
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I didn't say your anus. I said Uranus. Oh, okay.
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He didn't discover my anus. Maybe your anus.
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I don't know who you've been hanging around anyway. That's cool.
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That's cool. All right. Well, that was very cool. All right.
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Here we go. This is Light Blinded Fool. And Light
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Blinded Fool says, hello, Dr. Tyson. Lord, nice. My name
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is Robin and I'm from Vermont. Yay.
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Love Vermont.
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Thanks for StarTalk. My brain is eating very well. My
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question is, what do you think will get to Alpha
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Centauri first? Missions such as Starshot or what NASA or
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what the NASA Advanced Concepts Program is putting together? Or
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will nanotechnology evolve? and new propulsion systems outpace these programs
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if they are launched years later, and could these missions
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continue beyond Alpha Centauri to more distant stars since they
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won't be slowing down?
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Well, so this is why we have telescopes, so we
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can get a close-up look without actually going there. I mean,
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just think about that, okay? You have some object in
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the distance, you can travel to it or you can
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whip out a telescope and view it as though you
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were standing close to it. And even take measurements. And
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even take measurements. So the urge to be in a
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place that you could otherwise get measurements via a telescope
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is reduced simply because we have access to telescopes in
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multiple wavelengths with multiple detectors and the like. Okay, so
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that's my first comment. Second, Starshot, Project Starshot, is ambitious. Okay.
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They're going to have sent posted stamp sized spacecraft where,
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cause so much as can be miniaturized today that can monitor, uh, uh, temperature,
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magnetic fields, uh, uh, thermal fluxes, all in a tiny
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little posted stamp sized spacecraft that is attached to a
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huge solar sail. Light sail, I should call them.
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Okay.
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Now, the idea is you launch boatloads of these, and
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then you have gigawatt lasers on Earth that beam into
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these light sails to accelerate this very low-mass spacecraft.
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Awesome.
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And the calculations show, and by the way, if you
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beam light into a reflective surface, the momentum of the
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light will be imparted on that surface, and you can
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accelerate it. the calculations show that beaming at these spacecraft
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from Earth, even as they increase their distance, you can
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get the speeds up to 20% the speed of light.
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Dang! I know!
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I know! Now, let's do the math. The Alpha Centauri
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system is four light years away. So, how long will
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it take these objects to get there?
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At 20% the speed of light?
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Speed of light, uh-huh. And they're four light years away.
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20 years, exactly. Thanks for that good math on the spot.
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So it'll take 20 years to get there. And so
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to say, is there some other propulsion, some other technology
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that we can do within the 20 years that those
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are in motion that'll just somehow pass them by? I
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don't think so. I don't think so.
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How are you getting faster than 20% the speed of light?
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I don't see that happening. And so- And just for context,
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the fastest spacecraft we've ever launched anywhere was the mission
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to Pluto called New Horizons. And the reason why that
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was fast is we have a rule, unwritten, but it's
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definitely a rule. If you're head of a space mission,
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you want to make sure that it's completed before you die.
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That's an unwritten rule. And so Pluto is very far away.
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With normal rockets, it might have taken dozens of years,
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but you make the payload as light as possible, give
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it low mass, and boost it on the most powerful
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rockets in the space launch arsenal. This gives you very
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high acceleration from Earth out to Pluto. If instead you
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redirected that rocket to Alpha Centauri, lest I calculated this,
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It would take you 40 to 50,000 years to get
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to Alpha Centauri.
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That's wild.
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That's very different from 20 years. Yeah.
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Good time. Yeah.
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And that's the fastest thing we've ever launched. So I don't,
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you know, we're good. This Project Starshot, there's good Google
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pages on it. You can check it out. And I
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think it was one, it might've been one of the
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X prizes. I have to check my memory on that.
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But anyhow, go check out Project Starshot. Very ambitious, and
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I think realizable, by the way. It is. Might need
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a few more billionaire investors, but yeah.
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Very cool. This is Lyra, who says, Dr. Tyson, Lord, nice.
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Vega from Colorado here.
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Wait, wait. Hold on. How do you spell Lyra?
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L-Y-R-A.
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So that's the name of a constellation.
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Okay.
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Now let's keep going.
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Vega says.
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Vega is the name of the brightest star in the
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constellation Lyra.
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There you go.
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I'm just saying, are we dealing with an alien here? Maybe. Maybe. Maybe.
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This is a code. Let's see. Let's see what Lyra
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says or what Vega says. You talked in previous episodes
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about there being no functional now. Regarding a moving person
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00:22:50.460 --> 00:22:53.359
and a still person looking up in the sky at
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Andromeda at the same place and time and seeing it
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years in the past while moving and the present and
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present while standing. My question is, is there any way
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we can make a simulation to replicate what true now
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would be if it were able to exist? Or is
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our knowledge or understanding unable to comprehend how we could
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even begin to do that?
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Yeah, no. Now is a very personal, individual thing. And
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00:23:29.609 --> 00:23:32.289
by the way, By the way, let me be precise.
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The now as in your clock time, okay? So we
401
00:23:38.190 --> 00:23:43.380
can all have a now, but in what was once
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00:23:43.539 --> 00:23:47.420
synchronized clocks will show up in this case, three different
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00:23:47.460 --> 00:23:53.339
nows for you, me, and Vega or Lyra, whatever that
404
00:23:53.359 --> 00:23:53.960
person's name is.
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Whatever this alien's name is.
406
00:23:56.710 --> 00:24:00.779
Right, right. So no, you cannot construct an absolute now.
407
00:24:00.839 --> 00:24:03.339
That's kind of the whole... That's what we had to
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give up when we transitioned from classical physics to relativity physics,
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00:24:09.279 --> 00:24:11.579
to modern physics. What's related to that is we had
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to give up simultaneity. And that's the same question, in
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00:24:15.890 --> 00:24:21.190
a way, as asking about now. Because if things are simultaneous,
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00:24:21.210 --> 00:24:24.960
they're happening in the same now. But if there is no...
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00:24:25.859 --> 00:24:30.160
Absolute simultaneity that is further evidence that there is no
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00:24:31.119 --> 00:24:36.759
common now in the universe. So you can share a
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00:24:36.809 --> 00:24:38.690
now with someone else if you were together with the
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00:24:38.730 --> 00:24:41.890
same speed and the same gravitational field. But otherwise, no,
417
00:24:41.910 --> 00:24:44.670
just give up on it. It's hard to give up
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classical ways because our senses are forged in, like I said,
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00:24:48.950 --> 00:24:51.670
in the Serengeti to not get eaten by a lion.
420
00:24:52.170 --> 00:24:55.039
That's how and why our senses do what they do.
421
00:24:55.720 --> 00:24:59.779
Beyond that, you know, the universe is under no.
422
00:24:59.900 --> 00:25:02.839
Obligation to make sense to you.
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00:25:03.500 --> 00:25:03.940
Thank you.
424
00:25:04.140 --> 00:25:04.680
There it is.
425
00:25:05.079 --> 00:25:05.720
There you go.
426
00:25:06.819 --> 00:25:09.230
All right. Still a good question. I mean, nice to
427
00:25:09.250 --> 00:25:23.200
think about. This is Christian Jeremiah. And he says, hello from. Oh. Elulissat, Greenland.
428
00:25:23.299 --> 00:25:25.400
Never heard of it. So one of the ways to
429
00:25:25.579 --> 00:25:30.589
visualize gravity is through rubber fabric, a.k.a. bowling ball on
430
00:25:30.609 --> 00:25:35.819
a trampoline. And I believe that's known as the rubber sheet, right? Sure, sure. Okay.
431
00:25:36.119 --> 00:25:36.339
So does.
432
00:25:36.480 --> 00:25:38.839
Don't have your bone ball be anything would put a
433
00:25:38.880 --> 00:25:41.240
depression in that sheet. Yeah.
434
00:25:41.720 --> 00:25:46.180
Does mass stretch our third spatial dimension into fourth or
435
00:25:46.259 --> 00:25:51.630
higher dimensions the same way as rubber fabric? If it does,
436
00:25:51.869 --> 00:25:56.210
is there still downward gravity in higher dimensions? Oh, yeah.
437
00:25:56.250 --> 00:25:58.549
Have some fun with that, Neil, because... Whoa.
438
00:25:59.009 --> 00:26:05.240
Whoa. I'm trying to understand it because... The it's not
439
00:26:05.420 --> 00:26:07.660
simply that you have a rubber sheet.
440
00:26:07.950 --> 00:26:08.750
Exactly.
441
00:26:09.509 --> 00:26:11.710
Because in a rubber sheet, the way we normally think
442
00:26:11.750 --> 00:26:14.170
about that, there's like some big source of gravity in
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the middle of that.
444
00:26:14.970 --> 00:26:15.250
Right.
445
00:26:15.349 --> 00:26:18.529
And you put a test roller thingy and it rolls
446
00:26:18.549 --> 00:26:19.890
around and it goes into orbit.
447
00:26:19.930 --> 00:26:25.380
Right. It's to illustrate that the smaller body is falling
448
00:26:25.539 --> 00:26:29.819
towards the larger body. That's that's what it's supposed to illustrate.
449
00:26:29.920 --> 00:26:32.509
Correct. Except what that misses is. is the fact that
450
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everything has distortions in its rubber sheet. So the ball
451
00:26:38.349 --> 00:26:42.170
that's rolling around the curved rubber sheet has its own
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00:26:42.950 --> 00:26:47.140
distorted rubber sheet related to it. And so the universe
453
00:26:47.279 --> 00:26:52.220
is this juxtaposition of deformed rubber sheets for everything that's
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in it. From particles out to full galaxies. So we
455
00:26:56.589 --> 00:27:02.079
can't think of the mass itself as having some special
456
00:27:02.180 --> 00:27:06.319
kind of action on the fabric of space-time. Right. It's not.
457
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It just has the same action that anything else does.
458
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Right.
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And it corresponds with its total mass.
460
00:27:13.740 --> 00:27:14.559
Excellent.
461
00:27:15.019 --> 00:27:15.720
Very cool, though.
462
00:27:15.779 --> 00:27:19.559
But it's good that you asked that, because I'm sure
463
00:27:19.619 --> 00:27:23.869
when people see that demonstration online, because if you can
464
00:27:23.900 --> 00:27:27.369
go on YouTube, many places show that, I'm sure that's the...
465
00:27:29.099 --> 00:27:34.690
intuitive deduction that everybody makes is what he just asked.
466
00:27:35.210 --> 00:27:38.289
And in fact, in the original Hayden Planetarium, in the exhibits,
467
00:27:38.690 --> 00:27:42.829
we had one of these deformed surfaces, but it wasn't rubber.
468
00:27:42.869 --> 00:27:47.279
It was just a rigid, deformed surface. And you would
469
00:27:47.319 --> 00:27:51.819
take a, it's funny, my memory serves, you can take
470
00:27:51.859 --> 00:27:56.150
a coin and launch it And it would roll on
471
00:27:56.190 --> 00:27:59.079
its edge around the surface. So you send the coin
472
00:27:59.190 --> 00:28:03.579
into orbit around this sort of black hole thingy in
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00:28:03.619 --> 00:28:06.380
the middle. And then we keep your money.
474
00:28:09.299 --> 00:28:10.440
That's funny.
475
00:28:10.480 --> 00:28:14.099
It was the black hole fundraising mechanism. The only point
476
00:28:14.140 --> 00:28:17.849
that I'm making there is in that exhibit, that deformed
477
00:28:17.970 --> 00:28:22.119
sheet was rigid. It was a rigid sheet. sheet a
478
00:28:22.160 --> 00:28:25.779
rigid surface and you weren't thinking that even the coin
479
00:28:25.839 --> 00:28:29.069
would have deformations in it as well so i can
480
00:28:29.089 --> 00:28:31.450
see it's easy to see why you would think that
481
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the mass would be something separate and apart from whatever
482
00:28:34.150 --> 00:28:35.710
made the deformation in the first.
483
00:28:35.549 --> 00:28:42.099
Place right on okay let's move on to rachel ambrose
484
00:28:42.119 --> 00:28:47.099
that says hello rachel here from austin texas neil right
485
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are you familiar with hoag's object How statistically improbable is that?
486
00:28:53.480 --> 00:28:56.789
From our line of sight here on Earth, we'd see
487
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a ring galaxy and then billions of light years behind it,
488
00:29:01.190 --> 00:29:04.710
another ring galaxy that appears inside the first one. Do
489
00:29:04.789 --> 00:29:08.849
you think it's more than a coincidence? Maybe some kind
490
00:29:08.910 --> 00:29:12.230
of gravitational lensing effect?
491
00:29:13.049 --> 00:29:15.890
Okay, I didn't know it had a name. Tell me
492
00:29:15.930 --> 00:29:17.759
the name of it again. I know this object, but
493
00:29:17.819 --> 00:29:20.079
I didn't know it was named. What are we giving it?
494
00:29:20.640 --> 00:29:23.680
She called it Hoag's Object.
495
00:29:24.200 --> 00:29:26.759
So let's go back in time. You look up in
496
00:29:26.779 --> 00:29:31.869
the night sky and you see stars. And you ask yourself,
497
00:29:32.890 --> 00:29:35.690
I wonder if two stars that are kind of near
498
00:29:35.750 --> 00:29:38.849
each other in the sky are related to each other
499
00:29:38.869 --> 00:29:43.119
or are they just a chance? juxtaposition in space to
500
00:29:43.160 --> 00:29:46.619
our line of sight? That's a perfectly natural question. One
501
00:29:46.660 --> 00:29:53.309
of the earliest applications of statistics in science, which by
502
00:29:53.349 --> 00:29:56.289
the way happened way later than whole other branches of
503
00:29:56.349 --> 00:30:00.380
math were invented. I've written about that in in the
504
00:30:01.960 --> 00:30:08.180
risk and reward chapter of the book Starry Messenger, Cosmic Perspectives.
505
00:30:08.579 --> 00:30:13.059
I lament the fact that statistics is one of the
506
00:30:13.140 --> 00:30:16.349
last branches of math to be invented, which should tell
507
00:30:16.400 --> 00:30:21.869
us something about how ill-equipped our brain wiring is to
508
00:30:21.930 --> 00:30:26.349
think statistically about the world. And entire industries exist to
509
00:30:26.410 --> 00:30:31.900
exploit that ignorance. And they're called casinos, all right, where people, oh,
510
00:30:31.940 --> 00:30:34.930
my role is due. Oh, yeah, I feel lucky today.
511
00:30:34.990 --> 00:30:39.069
It's like what the brain does to think it is
512
00:30:39.210 --> 00:30:46.779
influencing events that are purely probabilistic is sad and tragic, okay?
513
00:30:46.819 --> 00:30:50.279
It is. We have a president who actually bombed a
514
00:30:50.339 --> 00:30:53.640
nation based on that same principle. What?
515
00:30:54.539 --> 00:30:54.759
Yeah.
516
00:30:54.799 --> 00:30:57.319
He said he had a gut. He had a gut feeling.
517
00:30:57.339 --> 00:30:57.900
Just a feeling.
518
00:30:58.180 --> 00:31:00.279
He had a feeling. Yeah. Yeah.
519
00:31:00.299 --> 00:31:04.619
I don't like people's guts. I don't like people's guts.
520
00:31:04.960 --> 00:31:08.210
I like people's brains better than I like their guts. Nice.
521
00:31:08.630 --> 00:31:09.170
I like that.
522
00:31:09.369 --> 00:31:13.369
So, can we pose this question mathematically and then arrive
523
00:31:13.410 --> 00:31:16.730
at an answer? And yes. So, what you can do
524
00:31:16.789 --> 00:31:19.589
is you can say, let's take a thousand stars and
525
00:31:19.670 --> 00:31:22.420
scatter them randomly on the sky.
526
00:31:23.079 --> 00:31:23.279
Mm-hmm.
527
00:31:23.990 --> 00:31:28.359
If you do it randomly, what fraction of them will
528
00:31:28.400 --> 00:31:32.799
be within a certain angular distance from each other? There's
529
00:31:32.839 --> 00:31:35.859
a certain number you would expect if they went up randomly.
530
00:31:36.519 --> 00:31:39.210
And random doesn't mean that they're exactly evenly spaced.
531
00:31:39.410 --> 00:31:39.650
Yeah.
532
00:31:39.869 --> 00:31:40.789
That is not random.
533
00:31:40.990 --> 00:31:44.809
Even if they were random, you could still get a clumping. Yes.
534
00:31:44.869 --> 00:31:46.210
In fact, clumpings are expected.
535
00:31:46.670 --> 00:31:46.990
Right. Right.
536
00:31:47.460 --> 00:31:49.420
This was the problem when people said, oh, he's got
537
00:31:49.440 --> 00:31:52.160
a hot hand in a basketball court. Give him the ball.
538
00:31:52.720 --> 00:31:56.099
When whatever is your shooting average in a game, you
539
00:31:56.140 --> 00:31:58.940
would expect there to be multiple shots in a row
540
00:31:58.980 --> 00:32:01.920
that are made. That's normal. It's not that he has
541
00:32:01.960 --> 00:32:06.160
a hot hand. That's normal. It's statistically normal. But again,
542
00:32:06.259 --> 00:32:10.019
we can't– our brains don't allow us to think statistically.
543
00:32:10.279 --> 00:32:13.180
We think something magic is going on. We think special
544
00:32:13.200 --> 00:32:16.900
kind of luck is happening. So– You do this and
545
00:32:16.920 --> 00:32:18.740
you know what to expect. Then we looked at how
546
00:32:18.759 --> 00:32:22.140
many stars are actually on the sky to a certain
547
00:32:22.180 --> 00:32:25.190
telescopic depth. And then we looked at how many were
548
00:32:25.230 --> 00:32:30.150
close by and there was a statistically significant increase in
549
00:32:30.230 --> 00:32:32.950
stars that were close to each other on the sky
550
00:32:34.019 --> 00:32:37.240
relative to random. And that was one of the first
551
00:32:37.319 --> 00:32:42.420
applications of statistics to assert that we actually have double
552
00:32:42.460 --> 00:32:46.660
star systems in the universe. Stars can be born in pairs.
553
00:32:46.720 --> 00:32:49.240
And then we said, let's keep going. The stars are
554
00:32:49.259 --> 00:32:54.119
born in triplets and quadruplets. And that opened the floodgates
555
00:32:54.599 --> 00:32:58.079
to think not only statistically about where stars are in
556
00:32:58.099 --> 00:33:00.980
the night sky, but also gravitationally and how you form
557
00:33:01.019 --> 00:33:01.720
such objects.
558
00:33:02.200 --> 00:33:02.460
Okay.
559
00:33:02.859 --> 00:33:06.230
You can do the same thing for galaxies. The same thing.
560
00:33:07.450 --> 00:33:13.059
And there are billions of galaxies. on the sky. So
561
00:33:13.440 --> 00:33:18.359
when you have that many galaxies, things such as alignments
562
00:33:18.460 --> 00:33:22.809
of two galaxies, you come to expect them. You don't
563
00:33:22.849 --> 00:33:25.670
go straight to them and say, Oh, this is interesting.
564
00:33:25.750 --> 00:33:29.069
And what an anomaly, what an anomaly. No, no, no, no, no.
565
00:33:29.329 --> 00:33:32.049
Look at the statistical likelihood of it. And we good.
566
00:33:32.569 --> 00:33:37.329
We good. We're good here. And, and, By the way,
567
00:33:37.390 --> 00:33:40.390
we have to be careful because when you do observe subsojects,
568
00:33:40.690 --> 00:33:45.170
you don't know initially if they're separate or related. And
569
00:33:45.559 --> 00:33:51.259
because they're two coherent things, two rings, you say, well,
570
00:33:51.279 --> 00:33:52.839
if they were on top of each other, could they
571
00:33:52.880 --> 00:33:56.079
still maintain their coherence? Their gravity might disrupt their shape.
572
00:33:56.400 --> 00:34:00.269
You can ask other sets of questions. Point is, it's
573
00:34:00.329 --> 00:34:03.130
not always obvious whether they're connected or not, and you
574
00:34:03.609 --> 00:34:04.569
need to do other measurements.
575
00:34:05.450 --> 00:34:11.079
Cool. Cool. Wow. All right. Still a good question. Thank
576
00:34:11.099 --> 00:34:14.659
you for the curiosity there, Rachel. We're all the better
577
00:34:14.699 --> 00:34:16.889
for it. All right. Let's go to Roark.
578
00:34:17.449 --> 00:34:17.809
You know what?
579
00:34:18.090 --> 00:34:21.230
I'm going to call him Rory. His name is Rory now.
580
00:34:21.329 --> 00:34:25.690
Your name is Rory now. Rory Campbell. Your name is
581
00:34:25.710 --> 00:34:27.809
Rory because Chuck cannot pronounce your name.
582
00:34:28.969 --> 00:34:30.889
No, it's either Roark or Roark.
583
00:34:31.489 --> 00:34:35.880
And that's R-O-A-R-K. Okay, it's Rourke.
584
00:34:36.440 --> 00:34:40.039
Rourke, okay. I would say Rourke. Not Rourke, Rourke. Okay,
585
00:34:40.059 --> 00:34:40.820
he says, hello, Dr.
586
00:34:40.860 --> 00:34:41.159
Tyson.
587
00:34:41.199 --> 00:34:43.400
I wonder if the answers to all of our universal
588
00:34:43.440 --> 00:34:47.309
questions lay within our ability to see further into geometry
589
00:34:47.349 --> 00:34:51.630
and fractal geometry patterns. Beyond botanical spirals and other phenomena,
590
00:34:51.889 --> 00:34:55.130
what if seeing clearly into space isn't what we actually need?
591
00:34:55.409 --> 00:34:59.019
Maybe something that helps us see kaleidoscopically, if you will,
592
00:34:59.260 --> 00:35:03.139
to uncover those patterns we cannot otherwise see. What is
593
00:35:03.199 --> 00:35:07.539
your take on this? You are a gentleman and a scholar. Also, Chuck,
594
00:35:07.579 --> 00:35:11.280
if you're reading this, I love you. Oh, that was nice. Okay.
595
00:35:11.739 --> 00:35:12.940
So what do you think?
596
00:35:16.420 --> 00:35:20.739
Shout out to Chuck. Yeah. So here's my take on that.
597
00:35:21.380 --> 00:35:23.179
I don't want to speak for the whole field, but
598
00:35:23.219 --> 00:35:24.139
here's my take.
599
00:35:24.659 --> 00:35:25.110
All right.
600
00:35:25.139 --> 00:35:29.230
Was it back in the 70s, but going definitely into
601
00:35:29.250 --> 00:35:33.630
the 80s, people started thinking a lot about fractals. Fractals
602
00:35:33.949 --> 00:35:37.880
are patterns that you can generate or occasionally find them
603
00:35:37.909 --> 00:35:40.539
in nature where when you zoom in, if there's some
604
00:35:40.579 --> 00:35:43.880
pattern that you see in a larger view and then
605
00:35:43.900 --> 00:35:46.139
you zoom in, that exact pattern gets repeated.
606
00:35:46.159 --> 00:35:47.980
That same pattern. Yeah.
607
00:35:48.079 --> 00:35:50.849
And you zoom in some more, it repeats again. Oh,
608
00:35:50.869 --> 00:35:55.210
they're beautiful. They're beautiful. And you can make beautiful fractal patterns,
609
00:35:55.989 --> 00:35:58.269
especially on a computer because computers are good at that.
610
00:35:59.190 --> 00:36:03.590
Here's an example. It's a mild example, but many plants,
611
00:36:03.650 --> 00:36:04.949
I don't know if there's two for all plants. You
612
00:36:04.969 --> 00:36:07.010
have to check with a botanist on this. If you
613
00:36:07.050 --> 00:36:10.489
look at a tree and you look at the angle
614
00:36:10.610 --> 00:36:14.239
that a branch comes off from the tree and measure
615
00:36:14.280 --> 00:36:17.039
that angle, it's usually upwards a bit, maybe 30 to
616
00:36:17.039 --> 00:36:19.739
60 degree angle from the vertical.
617
00:36:20.280 --> 00:36:20.539
Okay.
618
00:36:21.099 --> 00:36:24.670
Now that branch will have branches. Correct. Of course they will.
619
00:36:25.050 --> 00:36:27.449
This is what I mean by trees branching out. So
620
00:36:27.510 --> 00:36:29.349
let's look at the angle that that makes. It's the
621
00:36:29.409 --> 00:36:30.010
same angle.
622
00:36:30.510 --> 00:36:30.730
Okay.
623
00:36:30.750 --> 00:36:32.530
It's the same angle. And look at if they make
624
00:36:32.570 --> 00:36:35.869
a branch, what's that? That's the same angle. So if
625
00:36:35.889 --> 00:36:39.289
you just zoom in to this tree, you're getting a
626
00:36:39.889 --> 00:36:43.739
smaller tree, even smaller, smaller. You're getting versions of the
627
00:36:43.780 --> 00:36:46.519
larger tree as you zoom in. That's just kind of
628
00:36:46.559 --> 00:36:49.780
fun to notice if you've never noticed that about plants.
629
00:36:49.820 --> 00:36:53.179
I think it's a broader truth for plants just in general.
630
00:36:53.659 --> 00:36:56.949
There may be important exceptions to it. But if you
631
00:36:56.989 --> 00:36:59.570
just look at several plants, you'll see this repeating. And
632
00:36:59.590 --> 00:37:02.269
it's fun to notice, by the way. Oh, I got
633
00:37:02.309 --> 00:37:03.949
to throw this out there because I only learned it
634
00:37:03.989 --> 00:37:07.150
very late in life. If you cut an apple horizontally
635
00:37:08.650 --> 00:37:11.429
and you cut into the core and you will see
636
00:37:11.710 --> 00:37:16.820
seeds that are radially around the axis of the apple.
637
00:37:17.409 --> 00:37:18.739
Okay. Okay.
638
00:37:19.480 --> 00:37:23.440
Do you know how many seed sections there are? No,
639
00:37:23.460 --> 00:37:23.699
I don't.
640
00:37:24.329 --> 00:37:24.489
No.
641
00:37:24.730 --> 00:37:28.409
Okay, neither do I. I don't remember. But it's the
642
00:37:28.530 --> 00:37:34.699
same number as the petals on the flower that preceded
643
00:37:34.760 --> 00:37:35.219
that fruit.
644
00:37:36.300 --> 00:37:36.559
What?
645
00:37:37.440 --> 00:37:38.639
I know. I thought that was pretty cool.
646
00:37:38.980 --> 00:37:39.880
That is cool, man.
647
00:37:40.480 --> 00:37:41.110
That's pretty cool.
648
00:37:41.510 --> 00:37:41.969
Yeah.
649
00:37:41.989 --> 00:37:45.849
All right. That was cool. Okay. I'm not a botanist,
650
00:37:45.869 --> 00:37:47.809
so I'm not here to analyze that. I'm just here
651
00:37:47.829 --> 00:37:53.309
to just share with you that observation. Okay. Anyhow. So, fractals...
652
00:37:54.110 --> 00:37:58.750
There was the suspicion that fractals might be something in
653
00:37:58.809 --> 00:38:02.710
nature that we would be able to uncover. What makes
654
00:38:02.789 --> 00:38:07.010
fractals work is that the same rules that applied on
655
00:38:07.130 --> 00:38:08.909
one scale are applying on another scale.
656
00:38:09.429 --> 00:38:09.869
Right.
657
00:38:10.429 --> 00:38:13.670
It gives you the same thing. Right. In the universe,
658
00:38:14.590 --> 00:38:19.969
that's not how it works, okay? There are large-scale forces
659
00:38:20.170 --> 00:38:26.030
that do not readily translate to small scale forces. Because
660
00:38:26.130 --> 00:38:29.070
as you go to smaller in scales, quantum physics kicks
661
00:38:29.130 --> 00:38:31.789
in and that's not the same as Newtonian physics.
662
00:38:31.869 --> 00:38:33.289
And none of the rules apply.
663
00:38:34.869 --> 00:38:36.909
All the rules are different. All the rules are different.
664
00:38:37.429 --> 00:38:42.230
So you're not getting the pattern you're looking for. We
665
00:38:42.269 --> 00:38:44.880
want to think of patterns because it's easier for us
666
00:38:44.889 --> 00:38:49.610
to understand. It's philosophically easier for us to accept. And
667
00:38:49.670 --> 00:38:55.250
our brains are pattern machines. Yes. Pattern recognizing machines like
668
00:38:55.289 --> 00:39:00.780
there's never been any. So we're good at finding patterns,
669
00:39:01.300 --> 00:39:04.349
even when there's no pattern to be discerned. That's how
670
00:39:04.409 --> 00:39:06.880
good we are at finding patterns. So true.
671
00:39:07.559 --> 00:39:10.139
So true. Which is why I have a pancake in
672
00:39:10.199 --> 00:39:13.559
my refrigerator right now because I don't want to eat Jesus.
673
00:39:14.960 --> 00:39:15.960
He's on the pancake.
674
00:39:16.760 --> 00:39:18.489
No, I don't think Jesus shows up on pancakes. He
675
00:39:18.510 --> 00:39:19.300
shows up on tortillas.
676
00:39:20.050 --> 00:39:20.389
Oh, really?
677
00:39:20.429 --> 00:39:23.489
I don't think on pancakes. No, no. Okay. So my
678
00:39:23.610 --> 00:39:29.510
point is fractals ended up being more entertaining than useful.
679
00:39:30.699 --> 00:39:34.519
in the sciences. That's my only point. They're entertaining and
680
00:39:34.539 --> 00:39:37.079
they're beautiful and you can make fun art. But if
681
00:39:37.099 --> 00:39:39.679
you try to use it as a tool to probe nature,
682
00:39:40.179 --> 00:39:44.550
it's just simply not as useful. And in fact, they
683
00:39:44.590 --> 00:39:51.050
tried to model forests using fractal patterns for trees. Okay. Okay.
684
00:39:51.380 --> 00:39:54.500
Model it and for weather and for, and it just
685
00:39:54.800 --> 00:39:58.480
didn't work because the trees are different from each other.
686
00:39:58.619 --> 00:40:01.599
Even if one tree, even if one species of tree
687
00:40:01.679 --> 00:40:08.889
could be. fractaled into place, that same fractal model does
688
00:40:08.929 --> 00:40:11.429
not apply to all species of tree. It'd have to
689
00:40:11.469 --> 00:40:13.440
be a different fractal model and how many kinds of,
690
00:40:13.449 --> 00:40:16.989
there's thousands or however many species of tree. So it
691
00:40:17.030 --> 00:40:19.989
just became messy and awkward. And so I have not
692
00:40:20.130 --> 00:40:25.489
seen much reference to fractals helping scientists decode nature in
693
00:40:25.550 --> 00:40:28.320
the last 20 years. Yeah, that's my take on it.
694
00:40:28.780 --> 00:40:31.230
If there's a take I've missed, I'd be curious to
695
00:40:31.269 --> 00:40:34.409
know how fractals are coming along. But otherwise, I don't
696
00:40:34.530 --> 00:40:38.190
see them mattering as much as we thought they might have.
697
00:40:39.170 --> 00:40:39.510
All right.
698
00:40:39.610 --> 00:40:45.130
Well, listen, Rourke, just go ahead and continue to admire
699
00:40:45.750 --> 00:40:49.679
Romanesco broccoli and know that it has– It has no
700
00:40:49.760 --> 00:40:51.519
bearing on the universe at all.
701
00:40:52.820 --> 00:40:54.699
Romanesco broccoli is fractal food.
702
00:40:55.179 --> 00:40:55.480
Yes.
703
00:40:56.199 --> 00:40:58.969
Look up a picture of Romanesco. Find a picture of
704
00:40:59.010 --> 00:41:01.869
it online or buy it. And I'll have you know
705
00:41:02.449 --> 00:41:06.050
that in Star Wars Force Awakens, in the bar scene,
706
00:41:06.550 --> 00:41:09.210
one of the servers is walking by with a tray
707
00:41:09.909 --> 00:41:13.090
of crudités. And one of the objects on that tray
708
00:41:13.289 --> 00:41:14.429
is Romanesco broccoli.
709
00:41:15.119 --> 00:41:15.679
Oh, cool.
710
00:41:16.260 --> 00:41:22.550
All right. Evidence that that exists in a galaxy far away.
711
00:41:22.570 --> 00:41:23.309
Far, far away.
712
00:41:23.329 --> 00:41:28.230
There you go.
713
00:41:28.550 --> 00:41:30.849
It's either that or there's one hell of an importer
714
00:41:30.929 --> 00:41:39.500
on that planet. All right, this is Travis Knopp. He says, hello, Dr.
715
00:41:39.519 --> 00:41:45.579
Tyson and esteemed funny guest, Travis from Richmond, Virginia, with
716
00:41:45.619 --> 00:41:48.139
a question inspired by my two-year-old.
717
00:41:48.159 --> 00:41:48.320
Love it.
718
00:41:49.559 --> 00:41:54.780
She experiences a year as half her lifetime, while for me,
719
00:41:55.320 --> 00:42:00.420
it's only about 140th. Could there be a cosmic analog?
720
00:42:01.289 --> 00:42:04.369
When we see red-shifted light from a distant galaxy, we
721
00:42:04.429 --> 00:42:07.610
assume the universe was smaller when that light was emitted.
722
00:42:10.570 --> 00:42:13.280
Could the same observation be explained by a universe in
723
00:42:13.360 --> 00:42:18.900
which time, and thus the speed of light, passed differently
724
00:42:19.119 --> 00:42:22.360
in the past? And is there an observable test that
725
00:42:22.420 --> 00:42:26.489
distinguishes expanding space from changing time? Ooh.
726
00:42:29.440 --> 00:42:30.679
Interesting.
727
00:42:31.929 --> 00:42:33.210
Love it. Okay.
728
00:42:33.449 --> 00:42:36.730
So, they are related to each other. Let me get
729
00:42:36.769 --> 00:42:41.130
back to time relative to your two-year-old. Of course, your
730
00:42:41.170 --> 00:42:46.619
brain is– your life experience is filled by however long
731
00:42:46.659 --> 00:42:50.280
you have been having life experience, right? Right. So, you
732
00:42:50.300 --> 00:42:53.469
would expect– one year to, let's not take a two-year-old
733
00:42:53.489 --> 00:42:55.309
because they don't know anything about anything yet, a five-year-old.
734
00:42:55.789 --> 00:43:00.050
One year to a five-year-old is surely bigger in their
735
00:43:00.139 --> 00:43:02.860
life experience than one year to a 40-year-old, obviously.
736
00:43:03.480 --> 00:43:06.800
I lived a hard life, man. A lot of people
737
00:43:06.840 --> 00:43:09.980
think a five-year-old wouldn't know the ways of the world.
738
00:43:10.539 --> 00:43:14.420
But first of all, I quit smoking two years ago.
739
00:43:14.440 --> 00:43:20.920
And I just paid down my mortgage. Right. Here's something.
740
00:43:20.940 --> 00:43:23.599
I tried to quit my job this week.
741
00:43:28.789 --> 00:43:32.650
Really mature five-year-old. Yeah, exactly. So let me back into
742
00:43:32.670 --> 00:43:36.329
the answer to that question. When I was 14, I
743
00:43:37.849 --> 00:43:42.440
was driven with some other people approximately my age from
744
00:43:42.519 --> 00:43:44.139
New York City to the Mojave Desert.
745
00:43:44.860 --> 00:43:45.159
Wow.
746
00:43:45.880 --> 00:43:49.639
To attend an astronomy camp. where I lived nocturnally for
747
00:43:49.659 --> 00:43:54.250
a month. Wow. The trip, we drove nonstop, and the
748
00:43:54.329 --> 00:43:58.389
trip took two days and five hours. I didn't correct
749
00:43:58.409 --> 00:44:05.110
for time zone change, so it's two days and one hour. Okay. Okay.
750
00:44:05.590 --> 00:44:07.190
Is that right, or is it the other way? However
751
00:44:07.210 --> 00:44:09.090
you correct that for time zone. The point is it
752
00:44:09.130 --> 00:44:17.860
took two days. When we arrived, it seemed like We
753
00:44:17.880 --> 00:44:21.260
had left New York a week earlier because those two
754
00:44:21.300 --> 00:44:26.300
days were so filled with, oh wow, that's the St.
755
00:44:26.340 --> 00:44:27.000
Louis Arch.
756
00:44:27.079 --> 00:44:30.059
Oh my gosh, we're crossing the Mississippi River. Oh, is
757
00:44:30.079 --> 00:44:35.139
this Tennessee? Oh, is this Texas? My life was just,
758
00:44:35.570 --> 00:44:40.829
my visual mental awareness of the world was so full
759
00:44:42.170 --> 00:44:46.500
that my brain wouldn't allow me to say, Oh, that
760
00:44:46.539 --> 00:44:51.199
all happened in the last 48 hours. My brain forced
761
00:44:51.260 --> 00:44:53.559
me to think that that was spread over many more
762
00:44:53.639 --> 00:44:58.070
days than it actually was because the density of life
763
00:44:58.110 --> 00:45:02.469
experience was so high, was higher than anything I'd experienced
764
00:45:02.489 --> 00:45:06.070
in my life. So that was my mind's attempt to
765
00:45:06.130 --> 00:45:09.409
make sense of how much, how action filled those two
766
00:45:09.469 --> 00:45:13.389
days were. Anyhow, That's purely psychological and you can know
767
00:45:13.429 --> 00:45:16.750
this because you can bring measuring devices, clocks and things.
768
00:45:17.210 --> 00:45:19.670
And no, it didn't take me a week to get
769
00:45:19.710 --> 00:45:21.909
to California. It did only take two days. All right.
770
00:45:22.989 --> 00:45:27.639
In the expanding universe, it does affect time. It does.
771
00:45:28.579 --> 00:45:31.920
And I am proud to say I am a co-author
772
00:45:32.900 --> 00:45:37.440
on the first paper, research paper, to establish that fact.
773
00:45:38.940 --> 00:45:39.119
Okay?
774
00:45:40.320 --> 00:45:42.880
I forgot, it might have been as many as eight
775
00:45:43.079 --> 00:45:46.949
or nine authors on this paper. And the lead author
776
00:45:47.409 --> 00:45:51.969
would later win the Nobel Prize for co-discovering dark energy
777
00:45:52.349 --> 00:45:55.409
in the universe. So the lead author on that paper,
778
00:45:55.489 --> 00:46:00.440
his name is Brian Schmidt, who studied the, as we say,
779
00:46:00.480 --> 00:46:04.579
high redshift supernovae. These are stars that explode in galaxies
780
00:46:04.719 --> 00:46:06.679
out to the edge of the universe. And if you
781
00:46:06.739 --> 00:46:11.750
do that, you can probe metrics of the universe because
782
00:46:11.769 --> 00:46:15.429
all the supernova have a certain common properties. So it's
783
00:46:15.469 --> 00:46:20.929
like a yardstick, a free yardstick throughout the universe. And
784
00:46:21.150 --> 00:46:23.889
so he would ultimately share the Nobel Prize with Adam
785
00:46:23.949 --> 00:46:28.550
Ries for this discovery. And both those groups, the high
786
00:46:28.570 --> 00:46:31.300
redshift supernova groups, one was on the East Coast, one
787
00:46:31.320 --> 00:46:34.340
was on the West Coast. Brian Schmidt is now, last
788
00:46:34.380 --> 00:46:39.000
I checked, he was like provost in Australia, Australia National University,
789
00:46:39.059 --> 00:46:42.460
I think it is. But anyhow, so I'm on a
790
00:46:42.519 --> 00:46:48.030
research paper that showed that if you know when a
791
00:46:48.070 --> 00:46:50.699
star blows up a supernova, it gets brighter and then
792
00:46:50.719 --> 00:46:54.719
it gets dimmer at a very predictable rate. We know this, okay?
793
00:46:54.860 --> 00:46:58.380
That's why they make good yardsticks, standard candles as we've
794
00:46:58.400 --> 00:47:04.559
called them. There was a high redshift supernova that didn't
795
00:47:04.739 --> 00:47:08.070
fit this light curve. We call it a light curve.
796
00:47:09.710 --> 00:47:12.889
And we said, hmm, is this a different kind of supernova?
797
00:47:14.199 --> 00:47:14.619
Or what?
798
00:47:15.119 --> 00:47:18.659
Because this supernova hails from when the universe was half
799
00:47:18.719 --> 00:47:22.630
its current size and the universe was expanding as it
800
00:47:22.690 --> 00:47:28.289
still is. So what's up with that? Turns out if
801
00:47:28.349 --> 00:47:34.449
you put in the time dilation expected for the expansion
802
00:47:34.469 --> 00:47:37.829
of the universe at the time of that galaxy's light,
803
00:47:39.510 --> 00:47:44.000
it stretches the light curve to be exactly on the
804
00:47:44.039 --> 00:47:50.940
curve we measure. Holy shit. It was a direct evidence
805
00:47:51.679 --> 00:47:55.760
of not only a shift in the expanding universe, but
806
00:47:55.800 --> 00:48:00.170
what effect that has on time because the light curve
807
00:48:00.230 --> 00:48:05.760
was stretched out. Right. We observing that light curve, it
808
00:48:05.800 --> 00:48:08.800
took longer for that light curve to execute its rise
809
00:48:08.840 --> 00:48:12.679
and fall than a nearby supernova at exactly the rate
810
00:48:13.239 --> 00:48:19.070
that you'd expect from the expanding universe. And so I'm
811
00:48:19.110 --> 00:48:21.389
proud to be on there. I'd supplied some data, some
812
00:48:21.469 --> 00:48:24.929
supernova data that he compiled to make the full paper.
813
00:48:25.449 --> 00:48:28.469
So it's his effort to come up with that result.
814
00:48:28.969 --> 00:48:31.780
I was a cog in a much larger wheel. to
815
00:48:31.820 --> 00:48:36.199
make that happen. So the point is, yes, time is affected.
816
00:48:36.280 --> 00:48:40.730
And we see that in phenomena in galaxies and other
817
00:48:40.789 --> 00:48:43.889
phenomena in those places. And at those times in the
818
00:48:43.969 --> 00:48:50.090
early universe, but the, the speed of light as you
819
00:48:50.130 --> 00:48:52.699
measure it is the same, no matter what, no matter what,
820
00:48:52.719 --> 00:48:53.699
that's not what changes here.
821
00:48:54.179 --> 00:48:54.579
Right. Okay.
822
00:48:55.039 --> 00:49:01.010
But the time, the timekeeping timekeeping is what changes. And
823
00:49:01.090 --> 00:49:01.719
so there you have it.
824
00:49:02.489 --> 00:49:02.929
That's wild.
825
00:49:02.949 --> 00:49:03.590
All right.
826
00:49:03.610 --> 00:49:07.559
This is Kyle Holman. Kyle says, hello, Dr.
827
00:49:07.599 --> 00:49:07.980
Tyson.
828
00:49:08.039 --> 00:49:11.139
Lord, nice Kyle from Fort Myers, Florida here.
829
00:49:11.159 --> 00:49:12.559
Hey, Fort Myers.
830
00:49:14.360 --> 00:49:17.090
First time Patreon member. Welcome aboard.
831
00:49:17.469 --> 00:49:19.690
Welcome to the Star Talkiverse.
832
00:49:20.719 --> 00:49:24.579
Nice. There we go. What might the night sky have
833
00:49:24.699 --> 00:49:29.780
looked like when the cosmic microwave background radiation was cosmic
834
00:49:30.239 --> 00:49:33.099
visible light background?
835
00:49:33.679 --> 00:49:38.400
Oh, okay. So the cosmic microwave background today is microwave.
836
00:49:38.760 --> 00:49:39.619
It's microwave, that's right.
837
00:49:40.150 --> 00:49:40.550
Microwaves.
838
00:49:40.710 --> 00:49:40.969
Okay.
839
00:49:41.030 --> 00:49:46.929
The microwave photon is like one centimeter long or less.
840
00:49:47.530 --> 00:49:50.900
A few millimeters up to a couple of centimeters. It's
841
00:49:50.940 --> 00:49:56.400
the length, the physical length of the wavelength of the photon. Okay.
842
00:49:57.239 --> 00:50:01.590
That has stretched in the expanding universe since the cosmic
843
00:50:01.630 --> 00:50:08.690
microwave was first formed. Okay. So we ask, What was
844
00:50:08.750 --> 00:50:14.409
the temperature of the universe when it first formed? Because today,
845
00:50:14.929 --> 00:50:18.670
the temperature that corresponds with microwaves is three degrees Kelvin,
846
00:50:18.929 --> 00:50:24.039
absolute Kelvin, okay? The temperature of the cosmic microwave background
847
00:50:24.119 --> 00:50:29.320
when it formed was about 3,000 degrees. It turns out
848
00:50:30.039 --> 00:50:33.539
that there's an exact one-to-one relationship between how much the
849
00:50:33.579 --> 00:50:36.320
wave has stretched and how much bigger the universe is.
850
00:50:38.119 --> 00:50:42.949
So in the early universe, when its temperature was 3000
851
00:50:42.949 --> 00:50:48.650
degrees relative to three degrees today, it means the universe
852
00:50:48.710 --> 00:50:54.480
was one one thousandth its current size. Because over those years,
853
00:50:54.559 --> 00:50:58.550
it's expanded a thousand fold going from the wavelength of.
854
00:51:00.070 --> 00:51:03.250
Light at 3,000 degrees to the wavelength of light at
855
00:51:03.250 --> 00:51:03.550
3 degrees.
856
00:51:03.570 --> 00:51:04.309
At 3 degrees.
857
00:51:04.889 --> 00:51:07.130
And what is the wavelength of light at 3,000 degrees?
858
00:51:07.170 --> 00:51:07.829
It's visible light.
859
00:51:08.610 --> 00:51:13.530
So at one point, the whole universe was just a beautiful, like,
860
00:51:13.710 --> 00:51:14.829
heavenly light.
861
00:51:15.590 --> 00:51:18.869
Yes, a heavenly glow. But it would be like the
862
00:51:18.929 --> 00:51:22.269
surface of the sun, but everywhere. And if you had
863
00:51:22.349 --> 00:51:25.409
good measuring devices, you can detect that some parts were
864
00:51:25.610 --> 00:51:29.630
slightly cooler and slightly warmer than others. And that you'd
865
00:51:29.650 --> 00:51:32.719
be immersed in that, filled with it. And you wouldn't
866
00:51:32.739 --> 00:51:36.219
need special telescopes to see it. So when you say
867
00:51:36.300 --> 00:51:39.019
night sky, people often think of stars, suns, moons, and planets.
868
00:51:39.059 --> 00:51:41.400
Of course, none of that had formed yet because the
869
00:51:41.460 --> 00:51:44.820
universe is still trying to get its act together from
870
00:51:44.860 --> 00:51:45.650
those early moments.
871
00:51:45.889 --> 00:51:50.369
Yeah. Oh, that's cool. That is really cool. Damn.
872
00:51:50.389 --> 00:51:51.010
Yeah, all right.
873
00:51:51.050 --> 00:51:53.530
So you would have seen that and just been like,
874
00:51:53.730 --> 00:51:55.110
somebody turn that down.
875
00:51:55.809 --> 00:52:02.139
Yes, exactly. There'd be no, you couldn't get away from it. Right.
876
00:52:02.460 --> 00:52:03.519
It'd be everywhere.
877
00:52:03.539 --> 00:52:07.659
It's omnipresent, just light. And let me tell you how
878
00:52:07.760 --> 00:52:11.230
bad it actually would be. If you said, oh, there's
879
00:52:11.250 --> 00:52:13.349
some shade over there and you go under the shade,
880
00:52:14.050 --> 00:52:16.849
all of that energy will heat the thing that's shading
881
00:52:16.889 --> 00:52:20.750
you And then it will glow the same temperature as
882
00:52:21.130 --> 00:52:21.650
the background.
883
00:52:22.170 --> 00:52:22.530
Wow.
884
00:52:23.550 --> 00:52:27.250
Okay. So you wouldn't, you, there it is.
885
00:52:27.530 --> 00:52:28.230
Inescapable.
886
00:52:28.949 --> 00:52:29.530
Inescapable.
887
00:52:30.090 --> 00:52:32.719
Wow. Very cool. Oh man, that was good, man.
888
00:52:33.079 --> 00:52:35.460
Here's a quick thing. I don't know if you've done this.
889
00:52:35.800 --> 00:52:37.519
Have you ever done pottery where you have a kiln?
890
00:52:37.539 --> 00:52:38.960
Have you ever done this?
891
00:52:40.340 --> 00:52:44.739
I wouldn't quite call it pottery. I mean, I took some,
892
00:52:45.380 --> 00:52:49.469
I took some clay. and some water and supposedly shaped
893
00:52:49.489 --> 00:52:51.570
it into something. And then we put it in a
894
00:52:51.610 --> 00:52:53.889
little oven. And then when it came out, I was like,
895
00:52:54.010 --> 00:52:55.170
throw that shit away.
896
00:52:55.929 --> 00:53:01.380
Okay. Okay. So a kiln.
897
00:53:02.280 --> 00:53:02.460
Right.
898
00:53:02.960 --> 00:53:06.679
You know, where you fire up the kiln and you,
899
00:53:07.059 --> 00:53:11.809
it sets your clay in the oven. Okay. That is
900
00:53:11.989 --> 00:53:13.050
glowing hot.
901
00:53:13.389 --> 00:53:14.030
Yes, it is.
902
00:53:14.789 --> 00:53:18.389
Okay. It is glowing hot. It's hotter than red hot,
903
00:53:18.690 --> 00:53:19.710
a little hotter than red hot.
904
00:53:19.730 --> 00:53:19.969
All right.
905
00:53:20.230 --> 00:53:23.210
So there it is. That's about 3,000, call it 3,000.
906
00:53:23.210 --> 00:53:25.300
It might be as low as 2,000 degrees, but let's
907
00:53:25.320 --> 00:53:27.800
call it 3,000 degrees for the moment in the kiln.
908
00:53:28.409 --> 00:53:31.210
There it is. If you look inside, it's just glowing.
909
00:53:31.989 --> 00:53:35.730
You can't see the edges of the walls of the
910
00:53:35.750 --> 00:53:37.230
kiln because it's all glowing at you.
911
00:53:37.289 --> 00:53:37.869
That's true.
912
00:53:38.050 --> 00:53:41.530
Now watch. Now you take your pottery, put it in there.
913
00:53:42.449 --> 00:53:44.269
What is the temperature when you put it in there?
914
00:53:45.659 --> 00:53:47.900
What does it do or what is it?
915
00:53:48.539 --> 00:53:50.579
What is the temperature of your pottery when you put
916
00:53:50.619 --> 00:53:50.820
it in?
917
00:53:51.340 --> 00:53:53.440
Oh, it's whatever the atmospheric temperature is.
918
00:53:54.000 --> 00:53:57.079
Room temperature. Okay. So now you put it in, close
919
00:53:57.119 --> 00:54:01.380
the thing. And that pottery gets hotter and hotter and hotter.
920
00:54:01.820 --> 00:54:02.039
Right.
921
00:54:03.460 --> 00:54:06.800
You can watch this happen. It gets hotter and hotter
922
00:54:06.889 --> 00:54:10.849
and hotter until it reaches the same temperature as the
923
00:54:10.949 --> 00:54:12.010
glowing walls.
924
00:54:12.409 --> 00:54:12.769
Okay.
925
00:54:13.789 --> 00:54:20.400
And then it disappears. Because it is the same glowing
926
00:54:20.599 --> 00:54:24.719
temperature surface as everything else. Maybe if you move your
927
00:54:24.760 --> 00:54:27.139
head a little bit, you can catch some edges of it.
928
00:54:27.519 --> 00:54:29.460
But compared to what it was when you first put
929
00:54:29.480 --> 00:54:33.420
it in, when it's a discrete object glowing at a
930
00:54:33.800 --> 00:54:36.639
room temperature rather than the temperature of the kiln itself.
931
00:54:37.059 --> 00:54:41.989
So it's how to make something disappear in the background.
932
00:54:43.670 --> 00:54:47.150
And one last example, completely obscure, but I got to
933
00:54:47.190 --> 00:54:49.809
put it out there. In the film, which I highly recommend,
934
00:54:50.130 --> 00:54:57.920
because it's masterfully crafted and very sexy and it's a caper,
935
00:54:58.400 --> 00:55:04.800
it was the remake of The Thomas Crown Affair. Okay? Okay.
936
00:55:05.519 --> 00:55:09.010
It's a heist in the Metropolitan Museum of Art, except
937
00:55:09.329 --> 00:55:12.230
they didn't agree to get their name mentioned in the credits,
938
00:55:12.750 --> 00:55:19.469
I think. Okay. They don't want people heisting their paintings. Anyhow, anyhow,
939
00:55:19.969 --> 00:55:23.000
the thieves waited for the hottest day of the year.
940
00:55:23.019 --> 00:55:24.679
Okay.
941
00:55:25.920 --> 00:55:32.840
Then cut the air conditioning to the rooms so that
942
00:55:32.880 --> 00:55:40.289
the air got up to the temperature of the walls.
943
00:55:44.030 --> 00:55:49.429
And so the cameras, they have infrared cameras. When that happened,
944
00:55:50.090 --> 00:55:55.300
the infrared camera could not detect the paintings from the walls,
945
00:55:55.380 --> 00:55:59.500
from the air in front of it. And the whole
946
00:55:59.559 --> 00:56:05.860
scene went, not blank, the whole scene went uniform. And yeah,
947
00:56:06.039 --> 00:56:07.800
because all glowing at the same temperature.
948
00:56:08.320 --> 00:56:12.280
That's pretty cool. If you put the pottery in the
949
00:56:12.400 --> 00:56:17.179
kiln and look in the window, when it disappears, if
950
00:56:17.219 --> 00:56:24.210
you listen very, very closely, you can hear the pottery saying, I.
951
00:56:32.000 --> 00:56:39.150
Was referring only to the light waves, not the sound waves.
952
00:56:39.269 --> 00:56:40.750
That's a different conversation.
953
00:56:40.849 --> 00:56:44.889
Oh, another thing.
954
00:56:44.929 --> 00:56:47.119
By the way, If the temperature in the rooms go
955
00:56:47.179 --> 00:56:49.539
up to like 100 degrees, because it's like the hottest
956
00:56:49.579 --> 00:56:51.980
day of the year, and the walls go to 100 degrees,
957
00:56:52.239 --> 00:56:53.239
what's your body temperature?
958
00:56:53.239 --> 00:56:55.260
98 point whatever.
959
00:56:55.780 --> 00:56:58.260
Yeah, so that's near 100 degrees. So all of this
960
00:56:58.340 --> 00:57:03.030
just blends. It turns out. We have a higher density
961
00:57:03.389 --> 00:57:05.969
of infrared light coming off of us than the air does,
962
00:57:06.829 --> 00:57:09.889
but it still makes it much harder to figure out
963
00:57:09.909 --> 00:57:11.929
what's going on when everything is glowing to you at
964
00:57:11.969 --> 00:57:14.639
the same temperature. That's all. So that's a lot of
965
00:57:14.719 --> 00:57:18.900
obscure everyday references to something that started as a cosmological,
966
00:57:18.920 --> 00:57:22.960
a brilliant cosmological question about the cosmic microwave background.
967
00:57:23.860 --> 00:57:25.539
Nice. Well, thanks, Kyle.
968
00:57:25.559 --> 00:57:27.380
You got it. Yeah, I think that's all the time
969
00:57:27.400 --> 00:57:27.699
we have.
970
00:57:29.030 --> 00:57:29.659
Oh, well, this was fun.
971
00:57:29.670 --> 00:57:33.110
All right. Another installment of Cosmic Queries. Grab bag.
972
00:57:33.510 --> 00:57:37.010
Yeah. Gumbo. All of your bag.
973
00:57:37.070 --> 00:57:37.650
Gumbo.
974
00:57:37.690 --> 00:57:40.289
That I don't want to see no. See grab bag
975
00:57:40.309 --> 00:57:44.679
no now. And we glad when we come back. Guarantee.
976
00:57:46.340 --> 00:57:52.340
Whatever the hell you just said. Chuck, for those seeing
977
00:57:52.360 --> 00:57:55.039
this on video, I see on your back screen, it
978
00:57:55.099 --> 00:57:58.130
comes and goes, but you're Your Just Smart Enough video
979
00:57:58.210 --> 00:57:59.369
is still up on YouTube.
980
00:58:00.010 --> 00:58:01.469
That's correct. On our YouTube channel.
981
00:58:01.630 --> 00:58:03.710
Oh, thank you. On StarTalk's YouTube channel.
982
00:58:04.050 --> 00:58:04.389
That's right.
983
00:58:04.530 --> 00:58:07.250
And you recorded that and posted it New Year's Eve
984
00:58:07.309 --> 00:58:07.989
or New Year's Day?
985
00:58:08.340 --> 00:58:09.519
New Year's Day.
986
00:58:09.840 --> 00:58:14.320
New Year's Day. That's right. So it's you just telling
987
00:58:14.360 --> 00:58:15.400
it like you see it.
988
00:58:15.420 --> 00:58:18.139
Chuck and I's Just Smart Enough on the StarTalk YouTube channel.
989
00:58:18.239 --> 00:58:20.619
Go and download it and share it with your friends.
990
00:58:20.780 --> 00:58:21.320
It's free.
991
00:58:21.340 --> 00:58:24.010
Oh, got it. That's all the time we have, Chuck. Oh, man.
992
00:58:24.030 --> 00:58:24.469
This was good.
993
00:58:25.230 --> 00:58:29.099
I am Neil deGrasse Tyson, your personal astrophysicist. Keep looking up.
994
00:58:32.369 --> 00:58:32.969
Space fact.
995
00:58:34.010 --> 00:58:37.199
So life doesn't simply require the sun. It requires a
996
00:58:37.860 --> 00:58:41.219
source of energy. One source of energy is Earth itself
997
00:58:41.920 --> 00:58:45.440
in the form of hydrothermal vents. Places at the bottom
998
00:58:45.460 --> 00:58:49.159
of the ocean where heat is coming out. And there
999
00:58:49.199 --> 00:58:52.610
we find life forms as alien as anyone has ever
1000
00:58:52.639 --> 00:58:59.809
dreamt of. Thriving on geochemical energy from the depths of
1001
00:58:59.849 --> 00:59:53.800
the Earth. Thank you. Thank you. Thank you.