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Cosmic Colors, Stellar Mysteries & the Intricacies of Light: A Q&A Episode · Space Nuts: Astronomy Insights & Cosmic Discoveries

• 0:00
  Speaker 1: All right, let's rock and roll. Welcome to another episode
• 0:04
  Speaker 1: of Space Nuts. I am your host, Heidi Compo today
• 0:08
  Speaker 1: filling in for Andrew Dunkley, and I'm here with Professor Watson,
• 0:12
  Speaker 1: Astronomer at Large, Professor Fred Watson. Actually it's just say
• 0:20
  Speaker 1: If I just say Watson, it makes it sound like
• 0:22
  Speaker 1: this is a mystery podcast and not a space podcast.
• 0:25
  Speaker 2: That's right, elementary, my dear Watson.
• 0:30
  Speaker 1: All right, well, speaking of mysteries, we have a lot
• 0:33
  Speaker 1: of really good questions with mysteries for you to solve today.
• 0:37
  Speaker 1: And our first question comes from Rusty from Donnie Brook.
• 0:44
  Speaker 3: Okay, Andrew and Fritt, it's Rusty and Donnie Brook. I'm
• 0:47
  Speaker 3: sitting out in a.
• 0:48
  Speaker 4: Beautiful clean knot and looking June north to see lastly,
• 0:55
  Speaker 4: and it's quite close to the Twins castor and products
• 0:59
  Speaker 4: the Gemini Twins.
• 1:01
  Speaker 5: It's closest to Pollucks, which is it's an orange giant
• 1:08
  Speaker 5: star and it looks redder. Pollux looks redder than Mars.
• 1:18
  Speaker 3: And if we look to the southwest from there we
• 1:22
  Speaker 3: can see beetle juiced part of oryon that one looks
• 1:25
  Speaker 3: radder again.
• 1:26
  Speaker 5: So my question is when you.
• 1:31
  Speaker 3: Take a picture through a very large telescope and you
• 1:34
  Speaker 3: can really see these colors close up?
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  Speaker 6: How colorful are they?
• 1:40
  Speaker 3: Is a red.
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  Speaker 5: Giant as red as a as.
• 1:45
  Speaker 3: A tomato or a pillar box? And what about the
• 1:51
  Speaker 3: blue stars? How blue do they get? Is it like
• 1:54
  Speaker 3: when we call them red and blue? Is that faired?
• 1:58
  Speaker 6: Income?
• 2:00
  Speaker 3: Anyway?
• 2:01
  Speaker 2: Have a good one, and so I can imagine so
• 2:04
  Speaker 2: rusty is one of our regular questions Donnybrook Donnybrook in
• 2:09
  Speaker 2: Western Australia and always asking intriguing questions. And I think
• 2:13
  Speaker 2: what he's thinking of here is if you set yourself
• 2:17
  Speaker 2: at the eyepiece, for example, of the biggest telescope in Australia,
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  Speaker 2: the one that I used to be astronomer in charge
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  Speaker 2: of up in Kunabarabon, with its three point nine meter
• 2:29
  Speaker 2: diameter mirror, and you looked through an eyepiece at some
• 2:35
  Speaker 2: of these objects, what would you see? Would you see
• 2:37
  Speaker 2: the colors more richly than we do with a small
• 2:41
  Speaker 2: instrument And the answer is a bit a little bit
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  Speaker 2: disappointing really, because the colors are still subtle looking through
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  Speaker 2: a very big telescope. And I've actually done it with
• 2:55
  Speaker 2: the Angle Australian telescope. It's quite hard to get an
• 2:57
  Speaker 2: eyepiece on the telescope like that, because it's festooned with
• 3:00
  Speaker 2: spectrographs and auto guiders and instruments of all different kinds
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  Speaker 2: that don't have an eyepiece on them. But when you
• 3:08
  Speaker 2: look through, yes, you do see the colors Mars looking red,
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  Speaker 2: serious looking, dazzlingly white, some blue stars, the dual Box,
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  Speaker 2: which is a cluster of stars in the constellation of
• 3:23
  Speaker 2: the Southern Cross, so name because it's got stars of
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  Speaker 2: different colors, including a particularly red one, which is a
• 3:31
  Speaker 2: sort of ruby colored stars. Those colors are exaggerated, but
• 3:35
  Speaker 2: perhaps not as much as you think.
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  Speaker 7: They would be.
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  Speaker 2: Rusty they you know, they don't go deep red or
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  Speaker 2: anything like that. The colors are still as supple as
• 3:46
  Speaker 2: you see them. But if I can put it this way,
• 3:48
  Speaker 2: it's just like sliding up the saturation button on your
• 3:51
  Speaker 2: color editor in whatever whatever photo editing system you use.
• 3:58
  Speaker 2: Slide up saturation a bit, and you get a bit
• 4:00
  Speaker 2: more color. Likewise, with the size of a telescope. What
• 4:04
  Speaker 2: you might be surprised at, though, is that the detail
• 4:09
  Speaker 2: that you see with a big telescope is not as
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  Speaker 2: fine as you'd expect. And that's all about the way
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  Speaker 2: the atmosphere behaves the atmosphere in terms of the way
• 4:22
  Speaker 2: turbulence in the atmosphere spoils the view through a telescope.
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  Speaker 2: It's actually far less forgiving of a big telescope than
• 4:28
  Speaker 2: is in a smaller one. A smaller one you might
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  Speaker 2: just see the object moving around, but you can see
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  Speaker 2: it quite sharply, whereas with a big telescope it just
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  Speaker 2: tends to blur it out.
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  Speaker 7: It still moves it.
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  Speaker 1: Whatever totally thought it was the other way around. I
• 4:41
  Speaker 1: would have thought those big telescopes were like hide four
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  Speaker 1: K perfect picture they are.
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  Speaker 2: With modern technology. These not really new, they've been around
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  Speaker 2: for thirty years, but it's only within the last decade
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  Speaker 2: that they've been perfected what we call adaptive optic systems,
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  Speaker 2: which actually it's all about the turbulence the mirror and
• 5:02
  Speaker 2: the telescopes themselves. If they were in space, they would
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  Speaker 2: reveal perfect images exactly like the web telescope or the
• 5:08
  Speaker 2: humble telescope do. But because they're at the bottom of
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  Speaker 2: an atmosphere with a lot of turbulence in the air,
• 5:15
  Speaker 2: even on top of mountains, it's turbulence that's what spoils
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  Speaker 2: the view. But modern technology lets you sense that turbulence.
• 5:23
  Speaker 2: It lets you see what is the distortion that the
• 5:27
  Speaker 2: atmosphere is providing, and then just like a pair of
• 5:30
  Speaker 2: noise canceling headphones, it cancels it out. It provides the
• 5:34
  Speaker 2: opposite signal, so it cancels out the turbulence. It's very
• 5:40
  Speaker 2: hard technology because you have to measure the star use
• 5:45
  Speaker 2: what's called a reference star, which is sometimes artificial. You've
• 5:50
  Speaker 2: got to measure that star a thousand times a second
• 5:53
  Speaker 2: for this process to work. So it needs very fast
• 5:56
  Speaker 2: readout sensors, much faster than what you find in for example,
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  Speaker 2: a mobile phone, but the same sort of thing, but
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  Speaker 2: they're reading out a thousand times a second at least,
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  Speaker 2: in fact, sometimes twice that.
• 6:08
  Speaker 1: That is so incredible. I just every day. I'm so
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  Speaker 1: proud of humanity for what we've come up with. It's
• 6:13
  Speaker 1: just fantastic to think. And if you know, if we
• 6:16
  Speaker 1: all just work together as a team, this would be
• 6:19
  Speaker 1: you know, we'd already have you know, gone past our
• 6:22
  Speaker 1: own solar system by now if we all worked as
• 6:24
  Speaker 1: a big team. That is so incredible just to think
• 6:26
  Speaker 1: of all the details of these technologies.
• 6:31
  Speaker 6: Let's take a little break from the show to tell
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  Speaker 6: the details. Of course, they are in our show notes.
• 9:03
  Speaker 6: Now back to the show. Okay, we take a.
• 9:07
  Speaker 1: Space nuts Well, our next question is from Dan from California,
• 9:13
  Speaker 1: Dan the Man. He says, I was reading about gamma
• 9:17
  Speaker 1: ray bursts and how devastating they can be should they
• 9:21
  Speaker 1: hit Earth. Can you explain why gamma ray bursts become
• 9:24
  Speaker 1: less lethal the further away they are because the majority
• 9:27
  Speaker 1: of space is avoid rather than dust. I assume the
• 9:31
  Speaker 1: same goes for radio waves, where over distance they get
• 9:34
  Speaker 1: weaker and weaker. Is this really due to dust and
• 9:38
  Speaker 1: gas that are weakening the signals?
• 9:40
  Speaker 4: Thanks?
• 9:44
  Speaker 2: Yes, it's actually nothing to do with dust and gas. Dan, Sorry,
• 9:49
  Speaker 2: wrong name, reading the wrong bit of the question. Dan.
• 9:54
  Speaker 2: The reason why things get weaker the further away you
• 9:58
  Speaker 2: get is because of a fundamental law of physics which
• 10:01
  Speaker 2: is called the inverse square law. And that is that
• 10:06
  Speaker 2: if you double the distance that you are from a
• 10:09
  Speaker 2: source of gamma rays or radio waves or whatever, you
• 10:12
  Speaker 2: double the distance, the signal drops by a factor of four.
• 10:16
  Speaker 2: It's the square of the distance. That's why it's called
• 10:18
  Speaker 2: the inverse square or so double the distance you get
• 10:23
  Speaker 2: you know, a quarter of the signal, and if you
• 10:26
  Speaker 2: then double the distance again, it goes down by an
• 10:30
  Speaker 2: equally large you know, it goes down by the square
• 10:33
  Speaker 2: of the new distance. A new distance is four, so
• 10:35
  Speaker 2: it goes down by sixteen, a factor of sixteen. And
• 10:38
  Speaker 2: that's why all these signals get weaker. Dust and gas
• 10:43
  Speaker 2: do impact on them. And for example, perhaps the best
• 10:48
  Speaker 2: example of that is the center of our Milky Way
• 10:51
  Speaker 2: galaxy at a distance of about twenty five thousand light years.
• 10:56
  Speaker 2: We can't see the center of that with visible light
• 10:58
  Speaker 2: telescopes because of the dust that blocks our view. It's
• 11:02
  Speaker 2: dusty in the Milky Way, and the center of our
• 11:04
  Speaker 2: galaxy is hidden. Infrared radiation penetrates the dust, and that's
• 11:09
  Speaker 2: why we can actually see it, see the center of
• 11:11
  Speaker 2: our galaxy in infrared, but not with visible light. So
• 11:15
  Speaker 2: dust certainly has an effect, but it's the distance that
• 11:18
  Speaker 2: is the real effect. This inverse square or means, you know,
• 11:21
  Speaker 2: it's the square of the distance by which it drops
• 11:25
  Speaker 2: every time you move away.
• 11:28
  Speaker 1: I wonder if that's everyone has that crazy friend that
• 11:31
  Speaker 1: always is just on speaker phone. They're like, oh, I
• 11:33
  Speaker 1: don't want to hold the phone up to my head.
• 11:35
  Speaker 1: I don't want the base to get me. You're going
• 11:38
  Speaker 1: to hold my phone you know, two feet away from
• 11:41
  Speaker 1: my face and I'm going to shout into it so
• 11:43
  Speaker 1: everybody can hear my conversation. The mouse maybe they may
• 11:46
  Speaker 1: be under something.
• 11:47
  Speaker 2: Well, you're right that sound waves also are affected by
• 11:51
  Speaker 2: the inverse squail or. So if you double the distance
• 11:56
  Speaker 2: from the person who's yelling into their phone, then it's
• 12:00
  Speaker 2: going to go down by a factor of four. So
• 12:02
  Speaker 2: that you you know, try try and try, you know,
• 12:06
  Speaker 2: doubling the distance twice and it'll drop by a fighter
• 12:08
  Speaker 2: of sixteen.
• 12:10
  Speaker 1: Yeah, I can't hear you, all right. Our next question
• 12:15
  Speaker 1: is from Mike from the UK.
• 12:18
  Speaker 7: It might keep it from the UK. Here a very
• 12:21
  Speaker 7: quick question, if I may. I have heard many, many
• 12:24
  Speaker 7: questions over the years into you guys about terrorforming Mars,
• 12:29
  Speaker 7: which is obviously something that is beyond our capability, but
• 12:33
  Speaker 7: a lot of people dream about what about terrorforming Venus.
• 12:38
  Speaker 7: It's not something I've heard a lot about. Now obviously
• 12:41
  Speaker 7: it's probably still beyond our capability. So let's just talk
• 12:46
  Speaker 7: sort of theoretical. But would it just be a case
• 12:49
  Speaker 7: of blocking out some of the Sun's rays to cool
• 12:53
  Speaker 7: the planet down and potentially reverse that runaway greenhouse effect
• 12:58
  Speaker 7: that's happened on Venus, So potentially, just thinking outside the box,
• 13:03
  Speaker 7: possibly collide to asteroids together and let the debris catch
• 13:10
  Speaker 7: in the orbit of Venus, blocking out some of the
• 13:12
  Speaker 7: Sun and then cooling it down, or potentially even sort
• 13:16
  Speaker 7: of build a structure to block some of the Sun's rays.
• 13:21
  Speaker 7: And the other question as well. And like I say,
• 13:23
  Speaker 7: I know this is probably beyond our capability. But if
• 13:26
  Speaker 7: we did manage to do that and cool the planet down,
• 13:31
  Speaker 7: if we could get the conditions on Venus to be
• 13:34
  Speaker 7: similar to what they are on Earth, which would probably
• 13:39
  Speaker 7: never happen anyway, but would it stabilize or would the
• 13:44
  Speaker 7: greenhouse run away effect happen? Again? Is it too close
• 13:50
  Speaker 7: to the Sun to hold a stable atmosphere and a
• 13:55
  Speaker 7: similar temperature to Earth? Well, the show is my favorite
• 13:59
  Speaker 7: podcasting in the world. I'll listen to it all the time.
• 14:02
  Speaker 7: I think I've listened to just about every episode. So
• 14:05
  Speaker 7: regardless of whether you answer my question or not, please
• 14:08
  Speaker 7: keep up the good work and thank you very much
• 14:10
  Speaker 7: for you Tim.
• 14:11
  Speaker 2: Yeah, that's a great question, Mike, terraforming Venus. Venus is
• 14:17
  Speaker 2: so different from the Earth in its natural environment that
• 14:23
  Speaker 2: it's hard to think of a more Well, you can
• 14:25
  Speaker 2: think of more different planets, because exoplanets are even wider
• 14:29
  Speaker 2: in range. But yes, here we've got a planet with
• 14:31
  Speaker 2: the surface temperature of about four hundred and sixty degrees celsius,
• 14:34
  Speaker 2: hot enough to melt lead, hot enough that the rocks
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  Speaker 2: probably glow a dull red as well because of that temperature,
• 14:43
  Speaker 2: and an atmosphere whose pressure is one hundred times the
• 14:46
  Speaker 2: pressure of the Earth's atmosphere, laden with carbon dioxide. And
• 14:50
  Speaker 2: just to add to that lovely benign picture, in the
• 14:54
  Speaker 2: upper atmosphere, a drizzles sulfuric acid. So you've really got
• 14:58
  Speaker 2: a hellish circumstance for anybody on Venus. How could you
• 15:05
  Speaker 2: terraform it? Well, you're right, that's the fact that Venus is.
• 15:11
  Speaker 2: You know, it's much nearer the Sun than we are
• 15:13
  Speaker 2: on Earth. That contributes and goes back to the question
• 15:16
  Speaker 2: we were just talking about. It's the inverse squall or
• 15:20
  Speaker 2: so you're actually getting far more radiation than you might
• 15:23
  Speaker 2: think just by being you know, a few million killing
• 15:26
  Speaker 2: of a few tens of millions of killing meters nearer to
• 15:29
  Speaker 2: the Sun. The idea of blocking the Sun's light is
• 15:34
  Speaker 2: something that has been suggested quite seriously on Earth in
• 15:40
  Speaker 2: order to reduce the carbon footprint that we're all making.
• 15:46
  Speaker 2: If you launch I'm trying to remember who suggested it.
• 15:49
  Speaker 2: At first, it's somebody I know, and I can't remember
• 15:51
  Speaker 2: who it was. But if you launch a swarm of
• 15:55
  Speaker 2: spacecraft and put them at what we call the L
• 15:58
  Speaker 2: two point, the second the Grange point, which is a
• 16:01
  Speaker 2: stable position between any planet and the Sun where the
• 16:05
  Speaker 2: gravity balance is out, you put this swarm of spacecraft.
• 16:08
  Speaker 2: This was suggested for the Earth, but it would equally
• 16:10
  Speaker 2: apply to Venus. You could do the same thing to
• 16:13
  Speaker 2: try and block down the Sun's light. I'm not convinced
• 16:17
  Speaker 2: that that would actually have any positive effect on the
• 16:23
  Speaker 2: atmosphere of Venus. It would certainly cool the radiation that
• 16:26
  Speaker 2: it feels from the.
• 16:27
  Speaker 7: Sun, that.
• 16:30
  Speaker 2: The carbon dioxide rich atmosphere would still act as a
• 16:35
  Speaker 2: as a runaway greenhouse atmosphere, so I think you would
• 16:39
  Speaker 2: still have these very high temperatures and I don't think
• 16:44
  Speaker 2: there is any technology we could imagine that would change that.
• 16:48
  Speaker 2: And if you were going to think about terraforming somewhere,
• 16:52
  Speaker 2: and I should say it's pretty well impossible, but if
• 16:55
  Speaker 2: you were going to think of it, Mars will be
• 16:57
  Speaker 2: a better bet. You'd have to keep on terraforming though,
• 17:00
  Speaker 2: because Mars doesn't have enough gravity to hang onto an
• 17:03
  Speaker 2: atmosphere like the Earth's. So I think you're right that
• 17:07
  Speaker 2: you would not. You would not lose the runaway greenhouse effect.
• 17:11
  Speaker 2: It would not it would not go away.
• 17:13
  Speaker 1: Basically, Yeah, Venus is really I'm sorry, Venus. It's a terrible,
• 17:18
  Speaker 1: terrible planet. It's really, I think, pretty pretty nasty as
• 17:24
  Speaker 1: far as everything that's going on in that planet. But
• 17:27
  Speaker 1: you know, we we did it. Historically, used to think
• 17:31
  Speaker 1: that that was going to be the most similar closest planet,
• 17:34
  Speaker 1: too was and then we flew some satellites by it
• 17:37
  Speaker 1: and we're like, oh, that's terrifying.
• 17:40
  Speaker 2: But yeah, you're right, I mean it is similar. It's
• 17:43
  Speaker 2: virtually the same size as Earth. There's some new research
• 17:47
  Speaker 2: just been released actually, which I nearly thought we might
• 17:50
  Speaker 2: talk about on Space Nuts, and it's about the crust
• 17:53
  Speaker 2: of Venus. The because like the Earth, Venus, we don't
• 18:01
  Speaker 2: know what said it's core. It doesn't have a magnetic field,
• 18:04
  Speaker 2: so it's probably not an iron core like ours, a mantle,
• 18:07
  Speaker 2: a sort of soft rock above that, and a crust.
• 18:10
  Speaker 2: And we live on the Earth's crust, for example, which
• 18:13
  Speaker 2: is not very thick. It's thirty or forty kilometers thick,
• 18:16
  Speaker 2: which is quite slender. But the thinking is that Venus
• 18:21
  Speaker 2: has a much thicker crust and that there is what
• 18:24
  Speaker 2: we call convection, this heat rising or material rising because
• 18:29
  Speaker 2: of heat convection taking place in the crust of Venus,
• 18:33
  Speaker 2: which may be why Venus has the largest number of
• 18:36
  Speaker 2: volcanoes of any object known in the Solar System. Now
• 18:40
  Speaker 2: we don't know if they're active or not. This is
• 18:42
  Speaker 2: just counting craters from radar measurements of its surface. It's
• 18:46
  Speaker 2: got the largest number of certainly volcanic structures. And the
• 18:51
  Speaker 2: thinking now is that comes from convection in the crust
• 18:54
  Speaker 2: rather than convection in the mantle, which is what we
• 18:56
  Speaker 2: have here on Earth. Just a little factoid about Venus
• 18:59
  Speaker 2: that I think a tribute this to its reputation as
• 19:03
  Speaker 2: an ugly system.
• 19:06
  Speaker 1: Well, that is such a fun fact. I never knew
• 19:09
  Speaker 1: that about Venus.
• 19:16
  Speaker 7: Space nuts.
• 19:18
  Speaker 1: Our very last question is from Todd is from Utah.
• 19:23
  Speaker 1: I am also from Utah, So Todd, thank you for
• 19:26
  Speaker 1: representing our little state. Hopefully you're winding up for some
• 19:31
  Speaker 1: good weather there and I'll springtime and Salt Lake's always
• 19:35
  Speaker 1: really beautiful. And I don't know if you're a skier,
• 19:38
  Speaker 1: if you've got some good skiing in the season. But
• 19:41
  Speaker 1: that's my little plug to a fella Utah. His question is, Hello, gentlemen,
• 19:47
  Speaker 1: I have a question about the double slit experiment. Well, truthfully,
• 19:52
  Speaker 1: I have many questions about it, but let's just focus
• 19:55
  Speaker 1: on one for now. I have seen that some have
• 19:59
  Speaker 1: done this experiment by shooting individual photons at the double slit,
• 20:04
  Speaker 1: one at a time, yet this still produces an inference pattern. This,
• 20:09
  Speaker 1: of course boggles my mind. I've read that I've read
• 20:12
  Speaker 1: that this is an example of quantum super superposition and
• 20:18
  Speaker 1: that somehow those photons are interacting with themselves. Can you
• 20:22
  Speaker 1: and Fred please elaborate on what exactly we understand is
• 20:26
  Speaker 1: happening here? Is this something silly along the lines of
• 20:29
  Speaker 1: photons not being bound by time? Speaking of time? Thank
• 20:33
  Speaker 1: you for yours. Finally, I have an observational joke for you.
• 20:38
  Speaker 1: In three thy and twenty five years from now, life
• 20:41
  Speaker 1: on Earth will either be really good or really bad.
• 20:45
  Speaker 1: It's fifty to fifty. That is from uh Todd from Utah, USA.
• 20:51
  Speaker 1: Thank you so much for the joke Todd and the
• 20:53
  Speaker 1: question I like the joke.
• 20:55
  Speaker 2: A lot, but nobody I've told it to so far.
• 20:57
  Speaker 4: That's it.
• 20:58
  Speaker 2: So I'm obviously lose something in the retelling there. It's
• 21:02
  Speaker 2: a good one, thank you.
• 21:06
  Speaker 1: They're not laughing at that there.
• 21:07
  Speaker 2: Maybe, So yeah, anyway, the question, Yeah, this is and
• 21:13
  Speaker 2: just to you know, sort of fill in the backstory.
• 21:16
  Speaker 2: What are we talking about with the double slit experiment.
• 21:19
  Speaker 2: If you pass beams of light through two slits under
• 21:24
  Speaker 2: the right circumstance, they will interfere with one another, and
• 21:28
  Speaker 2: that means we will see bright and dark patterns because
• 21:31
  Speaker 2: of the way the waves mix. So waves of light
• 21:36
  Speaker 2: basically can add together or can cancel out, and it's
• 21:39
  Speaker 2: where they add together and cancel out that we see
• 21:41
  Speaker 2: these bright and dark patterns. I was very keen on
• 21:45
  Speaker 2: interferometry the technique of doing that and making measurements by
• 21:49
  Speaker 2: it when I was a young student. But so that
• 21:53
  Speaker 2: is basically it was the proof of the fact that
• 21:57
  Speaker 2: light is a wave motion, because Newton thought it was particles.
• 22:02
  Speaker 2: But it was demonstrated not long after Newton's time that
• 22:05
  Speaker 2: it was a wave motion by virtue of this double
• 22:08
  Speaker 2: slit experiment. At the beginning of the nineteenth century. But
• 22:12
  Speaker 2: now we know that light is particles and waves, and
• 22:19
  Speaker 2: sometimes maybe the way to imagine it is as wave packets.
• 22:23
  Speaker 2: These photons, particles of light are sort of also a wave.
• 22:29
  Speaker 2: That was the way we kind of looked at things,
• 22:31
  Speaker 2: perhaps in the fifties and sixties, that photons were packets
• 22:34
  Speaker 2: of waves, because that would let you then use particles,
• 22:37
  Speaker 2: but that they would still do this interference trick so
• 22:40
  Speaker 2: that proved they had a wave motion. Along comes quantum
• 22:44
  Speaker 2: theory that says particles are basically made of waves. They're
• 22:49
  Speaker 2: not just packets of waves. They're made of waves in
• 22:51
  Speaker 2: a very odd way. And that experiment that Todd has
• 22:59
  Speaker 2: referred to is the one that tells you that there's
• 23:03
  Speaker 2: something really peculiar going on, because if you shoot photons,
• 23:08
  Speaker 2: single photons through this double slit experiment one at a time,
• 23:12
  Speaker 2: so that they never come together in a wave method,
• 23:17
  Speaker 2: you still get the interference pattern building up that proves
• 23:20
  Speaker 2: that they're waves. And I think you know Todd's comment
• 23:24
  Speaker 2: about is it something silly like photon's not being bound
• 23:29
  Speaker 2: by time in a way it is. I think it's
• 23:34
  Speaker 2: more about the mystery of quantum entanglement, that these particles
• 23:41
  Speaker 2: are entangled together, which means that they behave like a
• 23:44
  Speaker 2: single particle. So if you've got one going through one
• 23:47
  Speaker 2: side of the slit or one part of the slit
• 23:49
  Speaker 2: one going through another, they're still part of the same object,
• 23:53
  Speaker 2: even if they're going through at different times. So that's perhaps, yes,
• 23:59
  Speaker 2: that they're not bound by time in that sense, but
• 24:01
  Speaker 2: I think it's more to do with the phenomenon of
• 24:03
  Speaker 2: quantum entanglement that things behave as though they're a single
• 24:07
  Speaker 2: quantum object even though they're quite separate. They're separated sometimes
• 24:11
  Speaker 2: by very large distances, but they have common behavior between them,
• 24:17
  Speaker 2: and I think that's how the double slit experiment arises
• 24:20
  Speaker 2: when you use photons separate photons. I probably left you
• 24:25
  Speaker 2: completely called the ID.
• 24:28
  Speaker 6: I thought this.
• 24:29
  Speaker 1: Was fantastic and all wait, completely over my head.
• 24:33
  Speaker 2: Yeah, but it's one of the sort of fundamental experiments
• 24:38
  Speaker 2: of physics that tells you that light is both a
• 24:41
  Speaker 2: wave and a particle, but the two somehow mixed together
• 24:44
  Speaker 2: in a very mysterious way. I think that's the bottom line.
• 24:47
  Speaker 1: Okay, Well, I think I can understand that it's a mystery,
• 24:51
  Speaker 1: and they miss I understood those words.
• 24:54
  Speaker 6: Yeah, oh wow.
• 24:56
  Speaker 1: I mean, once again, thank you so much, Brad, for
• 24:58
  Speaker 1: you always take such such patience and care with answering
• 25:02
  Speaker 1: these questions and making making things make sense and just
• 25:06
  Speaker 1: making it fun and relatable and just and just exploring
• 25:10
  Speaker 1: and thinking together. So thank you so much for everything
• 25:14
  Speaker 1: that you provided us with today.
• 25:17
  Speaker 2: It's a pleasure, Canidie, thank you for being the kernel
• 25:20
  Speaker 2: of the of the show by keeping it going. I
• 25:22
  Speaker 2: mean K E R N E L rather than con.
• 25:28
  Speaker 1: Much language is good interesting. Well, thank you so much
• 25:31
  Speaker 1: everybody for listening in to today's episode. This today's question
• 25:36
  Speaker 1: and answer episode of Space Nuts, and we will catch
• 25:40
  Speaker 1: you next week. I will be back here again for
• 25:43
  Speaker 1: just a couple more weeks and then you'll get your
• 25:44
  Speaker 1: dear sweet and your bat. But until then you're stuck
• 25:47
  Speaker 1: with me. Thanks again to those of you. I heard
• 25:50
  Speaker 1: that a few of you wrote in with some kind
• 25:52
  Speaker 1: words about me, so thank you so much. If you
• 25:55
  Speaker 1: guys had compliments, I appreciate that. But until next time,
• 26:00
  Speaker 1: we all will be signing off.
• 26:02
  Speaker 2: Thank you so much, Thank you, Heidian. Thanks all so
• 26:05
  Speaker 2: to Hugh in the background back in the studio keeping
• 26:07
  Speaker 2: us all honest. We'll see you Next Time.
• 26:14
  Speaker 7: The Space Nuts podcast available at Apple Podcasts, Spotify, iHeart Radio,
• 26:21
  Speaker 7: or your favorite podcast player.
• 26:23
  Speaker 6: You can also stream on demand at bides dot com.
• 26:26
  Speaker 7: This has been another quality podcast production from nights dot com.