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Become an Explorer and seek out unforgettable places 0:01:48.400 --> 0:01:51.840 while enjoying rewards everywhere you travel. Cards issued by JP 0:01:51.920 --> 0:01:55.920 Morgan Chase Bank NA Member FDIC subject to credit approval Offer, 0:01:56.000 --> 0:01:57.800 subject to change terms apply. 0:02:05.560 --> 0:02:08.320 Hey Ortay, As an artist, do you have a favorite 0:02:08.440 --> 0:02:12.480 color that you use for scientific cartoons or some colors 0:02:12.520 --> 0:02:13.760 more science y than others? 0:02:14.440 --> 0:02:16.680 Well, it depends on the science. I mean some science 0:02:16.680 --> 0:02:18.400 it's just more colorful than others. 0:02:18.919 --> 0:02:20.720 So then what's the color of physics. 0:02:21.440 --> 0:02:24.000 It kind of depends on the topic too. If it's 0:02:24.000 --> 0:02:26.520 about lasers, I might use red, or if it's about 0:02:26.520 --> 0:02:29.440 the sun, I might use a yellow. I've used Cian 0:02:29.600 --> 0:02:30.600 for particle physics. 0:02:32.280 --> 0:02:34.200 What makes particle of physics cian? 0:02:35.280 --> 0:02:38.160 I don't know that just kind of would seem like 0:02:38.360 --> 0:02:40.680 fit to the topic at the time. It just gives 0:02:40.720 --> 0:02:42.840 you the blues, yeah, Or if it's a red hot topic, 0:02:42.880 --> 0:02:46.400 I might go for a nice intense red. But for 0:02:46.440 --> 0:02:48.000 our books they usually go with purple. 0:02:48.080 --> 0:02:49.959 Yeah, what's purple about our curiosity? 0:02:50.360 --> 0:02:53.600 It's more about the process, you know. It's kind of 0:02:53.600 --> 0:02:57.120 mentally bruising, I mean mentally enlightening. 0:02:57.440 --> 0:02:59.560 I think it's a supervision of both of those. 0:03:00.000 --> 0:03:18.360 It's both blue and red, which makes purple. There you go. Hi, 0:03:18.400 --> 0:03:20.800 I'm Hoorham Mack, cartoonas and the author of Oliver's Great 0:03:20.840 --> 0:03:21.560 Big Universe. 0:03:21.919 --> 0:03:24.760 Hi, I'm Daniel. I'm a particle physicist and a professor 0:03:24.880 --> 0:03:27.720 at U See Irvine. And my daughter tells me I 0:03:27.760 --> 0:03:28.600 can't see mad. 0:03:28.919 --> 0:03:31.880 WHOA wait? Does that mean that you can't get mad 0:03:32.320 --> 0:03:34.400 or that you don't see the color red? 0:03:35.840 --> 0:03:38.080 Yes. As a parent of a stubborn toddler, I never 0:03:38.200 --> 0:03:43.280 once got mad, absolutely kept my cool every single moment. No, 0:03:43.440 --> 0:03:45.400 she and I disagree a lot about what to call 0:03:45.480 --> 0:03:48.400 various colors. And she's convinced I'm partially colorblind. 0:03:48.880 --> 0:03:51.280 WHOA have you ever had it checked? Maybe it's true. 0:03:51.560 --> 0:03:53.520 What does that mean? You can't tell colors apart or 0:03:53.560 --> 0:03:55.520 you can't seek certain colors? But how do you know 0:03:55.560 --> 0:03:56.240 you can't see them? 0:03:56.440 --> 0:03:58.560 You can do these tests where you're supposed to see 0:03:58.640 --> 0:04:01.640 numbers out of dots. But she just likes showing me 0:04:01.720 --> 0:04:04.120 lots of different shades and asking me to come up 0:04:04.120 --> 0:04:05.640 with names of them. And I'm always like, I don't 0:04:05.680 --> 0:04:08.840 know wild Mountain raspberry, and she's like, that's not red, 0:04:08.880 --> 0:04:10.000 it's purple or something. 0:04:11.720 --> 0:04:13.440 Sounds like she just likes to disagree with you. 0:04:13.960 --> 0:04:19.240 Yeah, I think I raised her right, Yeah, you raised 0:04:19.240 --> 0:04:21.719 her to make you read all the time. 0:04:22.320 --> 0:04:24.680 But anyways, Welcome to our podcast Daniel and Jorge Explain 0:04:24.760 --> 0:04:26.919 the Universe, a production of iHeartRadio in. 0:04:26.920 --> 0:04:30.080 Which we try to pencil in an explanation for how 0:04:30.120 --> 0:04:33.120 the universe works. We try to color inside the lines 0:04:33.160 --> 0:04:37.640 and help you understand how this incredible, glittering, beautiful, bizarre 0:04:37.720 --> 0:04:41.960 and crazy cosmos actually works. How all those quantum mechanical 0:04:42.000 --> 0:04:45.880 little particles come together to emerge into this incredible experience 0:04:46.040 --> 0:04:46.960 that we all enjoy. 0:04:47.200 --> 0:04:49.080 That's right. We try to paint a picture for you 0:04:49.120 --> 0:04:51.640 of our amazing and beautiful universe using all of the 0:04:51.760 --> 0:04:54.640 hues of the rainbow to try to communicate to you 0:04:54.720 --> 0:04:58.280 all the feelings and impressions that the universe has given 0:04:58.360 --> 0:04:59.360 us as a human race. 0:05:00.120 --> 0:05:02.719 In science is trying to build a bridge between our 0:05:02.839 --> 0:05:06.640 visceral experience, what you actually feel as a conscious entity, 0:05:07.040 --> 0:05:09.760 and our mental picture of what's out there in the universe, 0:05:09.800 --> 0:05:12.520 the mental model we're all putting together trying to explain 0:05:12.880 --> 0:05:16.400 how the universe itself, absent from our humanity, actually works. 0:05:16.720 --> 0:05:18.920 But in the end, we never probe that deep reality 0:05:18.960 --> 0:05:22.680 independent of our senses. We're only limited to understanding how 0:05:22.720 --> 0:05:25.760 it works as filtered by our eyes and ears and 0:05:25.760 --> 0:05:27.159 fingertips and everything else. 0:05:27.560 --> 0:05:29.440 Yeah, and as we look at the universe and filter 0:05:29.880 --> 0:05:32.359 it through our eye, sometimes it makes us red with 0:05:32.560 --> 0:05:35.120 anger about the things we don't understand, or blue about 0:05:35.120 --> 0:05:38.119 the things we may never understand, and sometimes maybe even 0:05:38.200 --> 0:05:41.000 green and envy of maybe possible aliens out there that 0:05:41.040 --> 0:05:46.480 have figured it out. Did it miss a color? Orange? 0:05:47.000 --> 0:05:49.360 Mass orange for a nice glass of orange trees? 0:05:49.760 --> 0:05:51.279 Aren't you glad you made that pun? 0:05:51.560 --> 0:05:52.000 Nice? 0:05:52.200 --> 0:05:55.119 All these things are part of our experience. The color 0:05:55.160 --> 0:05:57.839 purple in your mind is not actually part of the universe, 0:05:57.920 --> 0:06:01.200 is just part of your experience of the universe. Somehow, 0:06:01.200 --> 0:06:04.159 over the centuries and millennia, we have been able to 0:06:04.200 --> 0:06:06.680 piece together a picture of how the universe out there 0:06:06.800 --> 0:06:10.480 might actually work, perhaps independent of our senses, though of 0:06:10.480 --> 0:06:13.360 course we won't know until those aliens come and talk 0:06:13.400 --> 0:06:16.279 to us about the colors they see in the universe. 0:06:16.920 --> 0:06:19.360 Do you think they're a colored line too? Like Daniel, 0:06:19.720 --> 0:06:23.080 we think the answer to the universe is a light 0:06:23.160 --> 0:06:27.320 shade of lavender summer breeze. And then we end up 0:06:27.360 --> 0:06:28.560 disagreeing about what that means. 0:06:28.720 --> 0:06:30.960 Yeah. I think whatever answer they have, my daughter will 0:06:30.960 --> 0:06:32.920 disagree with him. That's how I raised her. 0:06:34.120 --> 0:06:36.480 Let's not put her in the greeting committee. 0:06:36.560 --> 0:06:38.479 I think we agree on that. Oh my gosh. Yes, 0:06:38.600 --> 0:06:40.840 let's not send Daniel's children to meet the aliens. 0:06:41.960 --> 0:06:45.200 Yeah, unless they start an intergalactic war. 0:06:47.279 --> 0:06:49.360 Maybe the colors are sacred to them. And if Hazel 0:06:49.400 --> 0:06:52.280 disagrees about what's purple and what's red, she's going to 0:06:52.320 --> 0:06:53.159 really piss them off. 0:06:53.480 --> 0:06:56.599 Yeah, or they might disagree about the color hazel itself. 0:06:57.279 --> 0:07:00.200 That's right. Yeah, exactly are. 0:07:00.160 --> 0:07:02.160 You called hazel if you're not the color of a 0:07:02.200 --> 0:07:05.640 hazel nut. That's it. Forget this human race. It doesn't 0:07:05.680 --> 0:07:06.200 make any sense. 0:07:06.200 --> 0:07:07.880 It doesn't make any sense. You know, we named her 0:07:07.920 --> 0:07:10.000 hazel before we knew her. But she does turn out 0:07:10.040 --> 0:07:13.440 to like the color hazel and hazel nuts, so there's 0:07:13.480 --> 0:07:13.760 a win. 0:07:14.000 --> 0:07:15.600 Yeah, but how do you know she's actually seen the 0:07:15.600 --> 0:07:19.320 color Hazel's hazel blind? 0:07:19.440 --> 0:07:20.560 M hazel blind. 0:07:20.640 --> 0:07:24.960 Wow, it's all hazy to her, it is. 0:07:25.280 --> 0:07:28.360 But we are fascinated by this concept of color, not 0:07:28.440 --> 0:07:30.840 just because it's such a visceral part of our experience, 0:07:31.280 --> 0:07:33.800 but because it's deeply connected to the physics of what's 0:07:33.800 --> 0:07:36.320 happening out there in the universe. It tells us something 0:07:36.320 --> 0:07:39.600 about how photons are wiggling, or how neutrinos are flying 0:07:39.600 --> 0:07:42.120 through the universe, if you're willing to apply red and 0:07:42.160 --> 0:07:45.160 blue shifts to them as well. So this concept of color, 0:07:45.240 --> 0:07:47.400 what we see what's out there in the universe. It's 0:07:47.560 --> 0:07:50.920 very confusing but also very illuminating about how the universe 0:07:51.000 --> 0:07:51.800 actually works. 0:07:52.280 --> 0:07:54.160 Yeah, there's a lot of physics in light and in 0:07:54.240 --> 0:07:56.800 all the colors. But then, as you said, it gets 0:07:56.800 --> 0:07:59.560 filtered through our eyes and our brains, and sometimes what 0:07:59.600 --> 0:08:02.720 we see is not quite what's out there, and maybe 0:08:03.280 --> 0:08:06.040 there might be things out there that are maybe impossible 0:08:06.160 --> 0:08:07.720 for us to experience. 0:08:07.920 --> 0:08:10.040 Well, that's right. We know that there are frequencies of 0:08:10.160 --> 0:08:13.320 light the humans can never experience, but are there also 0:08:13.600 --> 0:08:15.800 colors that are impossible to see? 0:08:15.960 --> 0:08:18.120 So to the end podcasts, we'll be tackling the question 0:08:23.320 --> 0:08:25.720 what is an impossible color? 0:08:26.280 --> 0:08:28.040 It sounds like a job for Tom Cruise. 0:08:28.400 --> 0:08:30.400 Dunt dunt du du dunt stunt. 0:08:32.200 --> 0:08:34.520 This color will self destruct after you view it. 0:08:34.640 --> 0:08:40.520 We need a movie in which Tom Cruise is a physicist. Yeah, 0:08:40.520 --> 0:08:41.840 I mean he'd have to wear a lot of like 0:08:41.880 --> 0:08:44.880 wigs and prosthetics. Of course, he can't look like Tom Cruise. 0:08:46.080 --> 0:08:47.920 Yeah, he's too sexy to be a physicist. Is that 0:08:47.960 --> 0:08:51.400 what you're saying. I didn't say that he violates some 0:08:51.520 --> 0:08:52.280 physical law. 0:08:53.320 --> 0:08:54.120 He's to orange. 0:08:54.559 --> 0:08:57.400 He's definitely very physical, even if he's not a physicist. Right, 0:08:57.480 --> 0:08:58.520 he does his own stunts. 0:08:58.600 --> 0:09:00.840 Yeah, that's right. Yeah, I wonder if he would do 0:09:00.920 --> 0:09:03.319 his own stunts in a physics movie. Like, would you 0:09:03.360 --> 0:09:05.959 actually sit on the couch all day? I mean, that's 0:09:06.559 --> 0:09:08.520 it's probably more dangerous and jumping off a cliff. 0:09:08.720 --> 0:09:11.480 Then you put all those professional nap stunters out of 0:09:11.520 --> 0:09:14.360 work and you can just take naps on film as. 0:09:14.200 --> 0:09:15.880 A Wait wait, wait, that's a career. I can be 0:09:15.920 --> 0:09:17.880 a stunt napper exactly. 0:09:18.480 --> 0:09:19.920 Oh man, there's a career for everything. 0:09:19.920 --> 0:09:21.200 They're doing it all this time for free. 0:09:21.280 --> 0:09:24.280 Daniel, you know that the sign of an advanced civilization 0:09:24.559 --> 0:09:29.200 is specialization, right, And I think once we've achieved stunt napping, 0:09:29.240 --> 0:09:32.760 we've reached the pinnacle of civilizations. The aliens will be impressed. 0:09:33.120 --> 0:09:37.840 Oh they might even hire us to nap for them. 0:09:37.960 --> 0:09:38.480 Well there's a. 0:09:38.400 --> 0:09:40.520 Twist ending, but yeah, this is an interesting question, the 0:09:40.600 --> 0:09:42.760 idea that there might be colors out there that are 0:09:42.880 --> 0:09:47.800 impossible to create, to experience, to see, to generate what 0:09:47.920 --> 0:09:49.439 side of the color spectrum. 0:09:49.000 --> 0:09:52.600 Are we Yeah, it's a complicated question because color is 0:09:52.640 --> 0:09:55.960 intimately connected with frequency, and we think about it as 0:09:56.000 --> 0:09:59.960 controlled by light, but really it's something inside our minds, 0:10:00.120 --> 0:10:03.200 something generated by our brain. It's an experience, and the 0:10:03.240 --> 0:10:05.600 colors you experience in the end come from the signals 0:10:05.600 --> 0:10:08.480 that travel up the optic nerve, which are not physical, 0:10:08.480 --> 0:10:11.880 they're just interpreted by your brain, and so it's interesting 0:10:11.920 --> 0:10:14.280 to think about whether there are colors that cannot be 0:10:14.320 --> 0:10:16.079 described by those signals. 0:10:16.320 --> 0:10:19.040 Oh boy, is this going to get into philosophy, Daniel, Like, 0:10:19.120 --> 0:10:20.680 what colors can a bat see? 0:10:22.880 --> 0:10:24.679 That's actually a great idea for paper. I'm going to 0:10:24.720 --> 0:10:26.120 write that when we're done with this episode. 0:10:26.600 --> 0:10:28.120 Yeah, what color is your bad wing? 0:10:28.400 --> 0:10:31.520 Everything in the end is philosophy if you care about 0:10:31.559 --> 0:10:33.920 what it means. Right, So if you're going to answer 0:10:33.960 --> 0:10:36.880 the question what does that mean anyway, then yeah, you're 0:10:36.880 --> 0:10:38.240 getting into philosophy. 0:10:38.480 --> 0:10:41.280 That sounds like a philosophical statement in itself, Daniel. 0:10:41.320 --> 0:10:43.040 The philosophy of philosophy. 0:10:43.280 --> 0:10:46.680 Yeah, you can get a phphphd. 0:10:45.800 --> 0:10:49.600 In recursive philosophy. 0:10:48.160 --> 0:10:51.760 In computer science philosophical puzzles. Well, as usually, we were 0:10:51.760 --> 0:10:53.959 wondering how many people had thought about this question of 0:10:54.000 --> 0:10:56.920 what is an impossible color? And so, as usual, Daniel 0:10:56.920 --> 0:10:59.680 went out there to the internet to ask people this question. 0:11:00.160 --> 0:11:02.599 Thanks very much to everybody who answers these questions for 0:11:02.640 --> 0:11:04.760 the podcast. If you would like to hear your voice 0:11:04.800 --> 0:11:07.840 on future episodes, please write to me two questions at 0:11:07.920 --> 0:11:09.440 danielan Jorge dot com. 0:11:09.600 --> 0:11:11.360 So think about it for a second. What do you 0:11:11.400 --> 0:11:15.000 think is an impossible color? Here's what people had to say. 0:11:15.640 --> 0:11:18.559 So color is just a construct of our brain decoding 0:11:18.559 --> 0:11:23.400 the frequency of electradiation. If you think about it and 0:11:23.559 --> 0:11:26.760 imagine our rods and cones were tuned a little wider 0:11:26.920 --> 0:11:31.040 and we could actually see an infrared and ultraviolet, and 0:11:31.160 --> 0:11:34.640 colors we can't see would be associated with those frequencies. 0:11:35.400 --> 0:11:38.600 So I guess every color associated with low frequency radio 0:11:39.320 --> 0:11:42.200 all the way to gamma rays would be impossible colors. 0:11:43.000 --> 0:11:46.200 If color is just how we perceive different wavelengths of light, 0:11:46.320 --> 0:11:49.160 and light can be in a huge range of wavelengths, 0:11:50.080 --> 0:11:52.400 it has something to do with the limits of the 0:11:52.440 --> 0:11:57.800 wavelength approaching either zero or infinity, where suddenly color doesn't 0:11:57.840 --> 0:11:59.120 make any sense anymore. 0:12:00.760 --> 0:12:06.280 An impossible color, oh, very interesting. I'm going to say 0:12:06.600 --> 0:12:12.840 some sort of combination of spectral outputs that are that 0:12:13.000 --> 0:12:17.160 is a different spectral resolution than what our the receptors 0:12:17.160 --> 0:12:20.560 of our eyes are able to something to do with 0:12:20.760 --> 0:12:21.760 color metamerism. 0:12:23.240 --> 0:12:26.559 The interesting answers. I feel like nobody pitched the idea 0:12:26.600 --> 0:12:30.000 that maybe it's a color that's made out of plant based. 0:12:30.160 --> 0:12:32.920 Proteins vegan colors. 0:12:33.000 --> 0:12:39.080 Wow, yes, No, no animals or creatures were harmed in 0:12:39.080 --> 0:12:40.040 the making of this color. 0:12:42.360 --> 0:12:45.000 I can't even imagine a way you might harm an 0:12:45.080 --> 0:12:47.240 animal to make a color you're talking about, like, oh, 0:12:47.320 --> 0:12:49.440 let's see red, We're going to spill something's blood. Like 0:12:49.440 --> 0:12:51.960 it seems pretty unnecessary. 0:12:51.920 --> 0:12:57.840 I think, Daniel, you just don't have this strong enough imagination. No, 0:12:57.920 --> 0:13:00.400 but there are colors that are based on or additionally, 0:13:00.440 --> 0:13:03.080 there are dyes that are based on like insects, like 0:13:03.960 --> 0:13:04.800 insect juice. 0:13:05.200 --> 0:13:07.280 Oh yeah, okay, interesting, But. 0:13:07.200 --> 0:13:09.760 I don't know how vegans draw that line. 0:13:09.840 --> 0:13:11.319 You know, we're gonna have to have some of them 0:13:11.320 --> 0:13:12.640 on the podcast to answer the question. 0:13:13.160 --> 0:13:16.480 Yeah, sounds like good question for Katie. All right, well, 0:13:16.520 --> 0:13:19.920 let's dig into this question of what an impossible color is. 0:13:20.080 --> 0:13:22.880 Whether it means we can't see it, we can't make it, 0:13:22.880 --> 0:13:26.120 it can't exist in the universe. Let's figure it out. So, yeah, 0:13:26.120 --> 0:13:28.360 you know, what are the basics of light and color? 0:13:28.600 --> 0:13:31.199 Yeah, so let's start outside the human brain before we 0:13:31.240 --> 0:13:34.080 get into like signal processing and all that stuff, and 0:13:34.200 --> 0:13:37.320 just begin with light. Right, light we know is made 0:13:37.360 --> 0:13:41.000 of electromagnetic fields. There are ripples in electromagnetic fields. So 0:13:41.320 --> 0:13:43.599 we have electrical fields that can be made by like electrons, 0:13:43.600 --> 0:13:46.640 and magnetic fields that are made by magnets. And light 0:13:46.760 --> 0:13:49.320 is a coupling of the electric fields and the magnetic 0:13:49.320 --> 0:13:53.360 fields together. Electric fields can induce magnetic fields, magnetic fields 0:13:53.400 --> 0:13:56.160 can induce electric fields. Light is like this perfect little 0:13:56.160 --> 0:13:59.000 packet where it's slashing back and forth between electric fields 0:13:59.000 --> 0:14:02.680 and magnetic fields in amazing harmony, and it can propagate 0:14:02.679 --> 0:14:05.880 through the universe, this little oscillation of the fields. And 0:14:05.960 --> 0:14:08.840 these oscillations have frequencies that have a wavelength, they have 0:14:08.880 --> 0:14:12.480 a frequency that relates to their energy. So if you 0:14:12.480 --> 0:14:14.199 have a beam of light, for example, coming out of 0:14:14.200 --> 0:14:17.000 a flashlight, it's actually made out of little photons, and 0:14:17.080 --> 0:14:20.520 each photon has a specific energy which has a specific 0:14:20.560 --> 0:14:24.400 wavelength and a specific frequency. So that's what light is, right, 0:14:24.560 --> 0:14:25.960 these packets of photons. 0:14:26.000 --> 0:14:27.960 So I have this laser and I'm shooting it and 0:14:28.000 --> 0:14:30.440 there are photons coming out of it, and each photon 0:14:30.720 --> 0:14:33.520 is like a wiggle in the electromagnetic field. Is that 0:14:33.560 --> 0:14:33.960 what it is? 0:14:34.120 --> 0:14:37.160 Yeah, each photon is a wiggle in the electromagnetic field, 0:14:37.240 --> 0:14:37.680 but it's. 0:14:37.520 --> 0:14:39.760 Not a wiggle that's like propagating like if I throw 0:14:39.800 --> 0:14:42.680 a pebble in a pond, it's not spreading out there 0:14:42.800 --> 0:14:44.720 like that, right, Like in a laser, these things are 0:14:44.720 --> 0:14:45.800 going in a straight line. 0:14:45.880 --> 0:14:47.880 These things are going in a straight line. And we 0:14:48.000 --> 0:14:51.240 just did a really fun but very confusing episode about 0:14:51.280 --> 0:14:52.840 how long is the photon? And if you didn't listen 0:14:52.840 --> 0:14:53.440 to that one. 0:14:53.360 --> 0:14:54.600 I was going to listen to it. But it's a 0:14:54.640 --> 0:14:58.960 little long. It was not a light topic. 0:15:00.000 --> 0:15:02.200 And that tells you that real photons out there in 0:15:02.240 --> 0:15:04.920 the universe are a little packets. They have a length 0:15:05.160 --> 0:15:07.960 that's determined by the spread of the frequency. So in 0:15:08.040 --> 0:15:10.680 a sort of idealized sense, you can imagine every photon 0:15:10.760 --> 0:15:13.520 has exactly one frequency. It's like a pure little packet 0:15:13.560 --> 0:15:17.280 of one energy, one wavelength, one frequency. But that's actually 0:15:17.320 --> 0:15:19.880 mathematically very confusing because if it was like that, it 0:15:19.920 --> 0:15:22.600 would be everywhere in the universe. And so to build 0:15:22.680 --> 0:15:25.040 up a little packet that actually moves through the universe, 0:15:25.040 --> 0:15:28.400 a little blob that stays together and flies through space, 0:15:28.640 --> 0:15:30.840 you have to have a little bundle of frequencies. So 0:15:31.280 --> 0:15:33.600 you know, blue photon is like a little spread of 0:15:33.720 --> 0:15:36.440 various blue frequencies, and a red photon is a little 0:15:36.480 --> 0:15:40.360 packet of a handful of differently red frequencies. 0:15:40.440 --> 0:15:42.320 And they're all going at the same speed, which is 0:15:42.360 --> 0:15:42.960 the speed of light. 0:15:43.280 --> 0:15:45.640 Yes, exactly, they all go the same speed even though 0:15:45.680 --> 0:15:48.160 they have a different wavelength and a different frequency, and 0:15:48.200 --> 0:15:50.440 the speed of light is the same across the spectrum. 0:15:50.680 --> 0:15:52.880 That's at least in our current theory. There are theories 0:15:52.880 --> 0:15:56.520 of physics like rainbow gravity, where different frequencies travel at 0:15:56.560 --> 0:15:58.920 different speeds and you get like weird effects around the 0:15:59.000 --> 0:16:01.160 edges of black holes are in their current theory physics, 0:16:01.160 --> 0:16:03.960 and according to all of our measurements, every photon travels 0:16:03.960 --> 0:16:05.080 at the same speed. 0:16:05.800 --> 0:16:09.200 And the spectrum of frequencies that light can have. It's 0:16:09.480 --> 0:16:13.480 basically one dimensional, right, Like there's only one knob for 0:16:13.560 --> 0:16:14.560 the frequency of light. 0:16:14.800 --> 0:16:16.680 Yeah, if you're going to think about a photon. 0:16:16.480 --> 0:16:19.200 From zero to infinity, hmm, But it's just a line, 0:16:19.280 --> 0:16:20.800 and if you were to draw a plot of. 0:16:20.760 --> 0:16:23.240 It, Yes, exactly, it's one dimensional. It's a great way 0:16:23.240 --> 0:16:26.080 to think about it. And it is infinitely dense, right, 0:16:26.120 --> 0:16:29.320 there's an infinite number of frequencies there. We think of 0:16:29.360 --> 0:16:31.800 these things as like, oh, they're quantum mechanical, so it 0:16:31.880 --> 0:16:35.200 must be discrete. Must be broken up into chunks, right, 0:16:35.200 --> 0:16:38.080 But the reality is that free objects, even free electrons, 0:16:38.360 --> 0:16:41.800 are not quantized in their energy levels. They're quantized in 0:16:41.840 --> 0:16:44.360 the number of photons. Like you can't have one point 0:16:44.400 --> 0:16:47.680 seven photons or two point two seven photons. You can 0:16:47.760 --> 0:16:51.160 have one or two or nineteen. But each photon can 0:16:51.200 --> 0:16:54.440 have any energy. There's no limitation, there's no quantitization, there's 0:16:54.480 --> 0:16:57.480 no descritization of the energy spectrum. But yes, it is 0:16:57.520 --> 0:16:59.040 one dimensional that. 0:16:59.360 --> 0:17:01.400 You know of the right, Like, is it possible that 0:17:01.520 --> 0:17:03.320 maybe frequency is quantized as well. 0:17:03.720 --> 0:17:06.240 Yeah, in our current theory, that's the case. There are 0:17:06.400 --> 0:17:09.880 theories of quantum gravity in which like space is pixelated, 0:17:10.080 --> 0:17:12.720 which would make like a minimum wavelength, and in that 0:17:12.840 --> 0:17:16.120 case every distance is quantized. In our current theories, there's 0:17:16.119 --> 0:17:19.080 no minimum frequency, but that doesn't actually really make sense 0:17:19.320 --> 0:17:22.399 below like the plank length, where every photon would like 0:17:22.440 --> 0:17:25.400 collapse into a black hole anyway, So it only really 0:17:25.440 --> 0:17:28.400 applies up to a very very high energy, but much 0:17:28.440 --> 0:17:29.879 higher than we could probe today. 0:17:30.160 --> 0:17:32.080 All right, So that's the physics of it. Now let's 0:17:32.080 --> 0:17:35.440 get into the biology of it. So when these photons 0:17:35.480 --> 0:17:39.120 hit our eyes, they create and experience in our brains. 0:17:39.400 --> 0:17:43.000 Yeah, I think there's one step before that, which is reflection. Like, 0:17:43.200 --> 0:17:46.119 let's imagine we're looking at a banana, right, why do 0:17:46.160 --> 0:17:48.919 we see the banana as yellow. We see the banana 0:17:48.960 --> 0:17:52.200 as yellow because white light hits the banana from the sun, 0:17:52.640 --> 0:17:54.679 and then some of it is absorbed and some of 0:17:54.720 --> 0:17:57.439 it is reflected. You start with almost every frequency of 0:17:57.480 --> 0:17:59.480 light you can see hitting the banana, but then the 0:17:59.520 --> 0:18:02.280 banana has chemicals in it and atoms, and those atoms 0:18:02.440 --> 0:18:05.360 prefer to absorb some colors and not absorb other colors. 0:18:05.720 --> 0:18:08.760 And so when you see yellow as banana, that means 0:18:08.960 --> 0:18:12.080 that the wavelength of light that is being reflected is 0:18:12.080 --> 0:18:14.760 a specific band in this case, like between five hundred 0:18:14.800 --> 0:18:17.960 and seventy and five hundred and eighty nanometers. So you 0:18:18.000 --> 0:18:20.560 see something as red, it's not because it's like absorbing 0:18:20.600 --> 0:18:23.360 the red light, right, It's because it's reflecting the red 0:18:23.400 --> 0:18:26.640 light and absorbing everything else. But then, yeah, it hits 0:18:26.640 --> 0:18:29.240 your eyeball, and those photons with a certain frequency are 0:18:29.280 --> 0:18:31.760 now going to be interacted with by your eye, which 0:18:31.800 --> 0:18:33.879 is like basically little observational device. 0:18:34.240 --> 0:18:37.680 But wait, the banana, So the banana absorbs all frequencies 0:18:37.800 --> 0:18:40.879 except maybe the kinds that are my brain will interpret 0:18:40.920 --> 0:18:41.479 as yellow. 0:18:42.119 --> 0:18:45.320 Yeah, not all frequencies, but all visible ones. Right, banana 0:18:45.320 --> 0:18:48.959 can't necessarily absorb all X rays and gamma rays or infrared, 0:18:49.200 --> 0:18:52.120 but in the visible spectrum. And again and not even 0:18:52.160 --> 0:18:54.080 all of that, right, Like you see it yellow because 0:18:54.119 --> 0:18:57.000 it's dominant in the yellow. It's never like intense and 0:18:57.080 --> 0:18:59.280 yellow and zero in every other frequency. 0:19:00.040 --> 0:19:02.399 It just peaks unless it's like a perfect banana, Like, 0:19:02.600 --> 0:19:05.080 is it possible to create a perfect banana that only 0:19:05.119 --> 0:19:07.719 reflects like one frequency of yellow. 0:19:08.040 --> 0:19:10.600 If you make a shade which only reflects one frequency 0:19:10.600 --> 0:19:13.280 of yellow, I think Hazel would call that perfect banana. 0:19:13.400 --> 0:19:14.760 That is a nice name for a yellow. 0:19:15.920 --> 0:19:18.080 Yeah, exact banana, yes. 0:19:18.560 --> 0:19:20.680 Exact scientific banana. 0:19:20.760 --> 0:19:23.200 Okay, So there's a reflection. And also I mean there's 0:19:23.200 --> 0:19:27.240 filtering too. But while we're talking about it, like it right, 0:19:27.280 --> 0:19:29.680