WEBVTT - What is an impossible color? 0:00:07.480 --> 0:00:10.200 Hey, Orgy. As an artist, do you have a favorite 0:00:10.320 --> 0:00:14.360 color that you use for scientific cartoons or some colors 0:00:14.400 --> 0:00:15.640 more sciency than others. 0:00:16.320 --> 0:00:18.560 Well, it depends on the science. I mean some science 0:00:18.600 --> 0:00:20.280 it's just more colorful than others. 0:00:20.760 --> 0:00:22.600 So then what's the color of physics? 0:00:23.320 --> 0:00:25.880 It kind of depends on the topic too. If it's 0:00:25.880 --> 0:00:28.400 about lasers, I might use red, or if it's about 0:00:28.400 --> 0:00:31.320 the sun, I might use a yellow. I've used cian 0:00:31.480 --> 0:00:32.519 for particle physics. 0:00:34.159 --> 0:00:36.080 What makes particle physics cian? 0:00:37.159 --> 0:00:40.040 I don't know. That just kind of would seem like 0:00:40.240 --> 0:00:41.840 fit to the topic at the time. 0:00:42.040 --> 0:00:43.599 It just gives you the blues. 0:00:43.440 --> 0:00:45.080 Yeah, Or if it's a red hot topic, I might 0:00:45.120 --> 0:00:48.760 go for a nice intense red. But for our books 0:00:48.760 --> 0:00:49.880 they usually go with purple. 0:00:49.960 --> 0:00:51.840 Yeah, what's purple about our curiosity? 0:00:52.280 --> 0:00:55.480 It's more about the process, you know. It's kind of 0:00:55.480 --> 0:00:59.000 mentally bruising, I mean mentally enlightening. 0:00:59.320 --> 0:01:01.520 I think it's position of both of those. 0:01:01.800 --> 0:01:20.280 It's both blue and red, which makes purple. There you go. Hi, 0:01:20.280 --> 0:01:22.720 I'm Hoorham Mack, cartoonas and the author of Oliver's Great 0:01:22.720 --> 0:01:23.440 Big Universe. 0:01:23.800 --> 0:01:26.680 Hi, I'm Daniel. I'm a particle physicist and a professor 0:01:26.760 --> 0:01:29.600 at U see irvine, and my daughter tells me I 0:01:29.640 --> 0:01:30.479 can't see mad. 0:01:30.840 --> 0:01:33.759 WHOA, wait, does that mean that you can't get mad 0:01:34.200 --> 0:01:36.280 or that you don't see the color red? 0:01:37.720 --> 0:01:39.960 Yes, As a parent of a stubborn toddler, I never 0:01:40.080 --> 0:01:44.360 once got mad. Absolutely kept my cool every single moment. 0:01:45.120 --> 0:01:45.160 No. 0:01:45.319 --> 0:01:47.280 She and I disagree a lot about what to call 0:01:47.360 --> 0:01:50.320 various colors, and she's convinced I'm partially colorblind. 0:01:50.760 --> 0:01:53.040 WHOA have you ever had it checked? Maybe it's true. 0:01:53.440 --> 0:01:55.400 What does that mean? You can't tell colors apart? Or 0:01:55.440 --> 0:01:57.400 you can't seek certain colors? But how do you know 0:01:57.440 --> 0:01:58.120 you can't see them? 0:01:58.320 --> 0:02:00.960 You can do these tests where you to see numbers 0:02:01.000 --> 0:02:03.760 out of dots. But she just likes showing me lots 0:02:03.800 --> 0:02:06.080 of different shades and asking me to come up with 0:02:06.160 --> 0:02:07.640 names of them. And I'm always like, I don't know 0:02:07.760 --> 0:02:10.919 wild Mountain raspberry, and she's like, that's not red, it's 0:02:10.919 --> 0:02:11.880 purple or something. 0:02:13.600 --> 0:02:15.320 Sounds like she just likes to disagree with you. 0:02:15.840 --> 0:02:18.400 Yeah, I think I raised her right. 0:02:19.200 --> 0:02:23.600 Yeah, you raised her to make you read all the time. 0:02:24.200 --> 0:02:26.560 But anyways, welcome to our podcast. Daniel and Jorge Explain 0:02:26.639 --> 0:02:28.800 the Universe, a production of iHeartRadio, in. 0:02:28.800 --> 0:02:31.959 Which we try to pencil in an explanation for how 0:02:32.000 --> 0:02:35.040 the universe works. We try to color inside the lines 0:02:35.080 --> 0:02:39.520 and help you understand how this incredible, glittering, beautiful, bizarre 0:02:39.600 --> 0:02:43.800 and crazy cosmos actually works, how all those quantum mechanical 0:02:43.880 --> 0:02:47.839 little particles come together to emerge into this incredible experience 0:02:47.919 --> 0:02:48.840 that we all enjoy. 0:02:49.080 --> 0:02:50.960 That's right. We try to paint a picture for you 0:02:51.000 --> 0:02:53.560 of our amazing and beautiful universe, using all of the 0:02:53.639 --> 0:02:56.520 hues of the rainbow to try to communicate to you 0:02:56.600 --> 0:03:00.120 all the feelings and impressions that the universe has in 0:03:00.240 --> 0:03:01.239 us as a human race. 0:03:01.440 --> 0:03:03.400 And in the end, science is trying to build a 0:03:03.440 --> 0:03:07.600 bridge between our visceral experience what you actually feel is 0:03:07.639 --> 0:03:10.680 a conscious entity, and our mental picture of what's out 0:03:10.720 --> 0:03:13.280 there in the universe, the mental model we're all putting 0:03:13.320 --> 0:03:16.720 together trying to explain how the universe itself, absent from 0:03:16.720 --> 0:03:19.440 our humanity, actually works. But in the end, we never 0:03:19.520 --> 0:03:22.960 probe that deep reality independent of our senses. We're only 0:03:23.040 --> 0:03:26.600 limited to understanding how it works as filtered by our 0:03:26.639 --> 0:03:29.080 eyes and ears and fingertips and everything else. 0:03:29.440 --> 0:03:31.320 Yeah, and as we look at the universe and filter 0:03:31.760 --> 0:03:34.280 it through our eye. Sometimes it makes us red with 0:03:34.440 --> 0:03:37.000 anger about the things we don't understand, or blue about 0:03:37.000 --> 0:03:40.000 the things we may never understand, and sometimes maybe even 0:03:40.080 --> 0:03:42.880 green and envy of maybe possible aliens out there that 0:03:42.920 --> 0:03:48.360 have figured it out. Did it miss a color? Orange? 0:03:48.880 --> 0:03:51.080 Mass orange? For a nice glass of orange? 0:03:51.640 --> 0:03:53.160 Aren't you glad you made that pun? 0:03:53.440 --> 0:03:53.880 Nice? 0:03:54.080 --> 0:03:57.000 All these things are part of our experience. The color 0:03:57.040 --> 0:03:59.680 purple in your mind is not actually part of the universe, 0:03:59.760 --> 0:04:03.080 is just part of your experience of the universe. Somehow, 0:04:03.120 --> 0:04:06.040 over the centuries and millennia, we have been able to 0:04:06.080 --> 0:04:08.560 piece together a picture of how the universe out there 0:04:08.680 --> 0:04:12.360 might actually work, perhaps independent of our senses, though of 0:04:12.360 --> 0:04:15.240 course we won't know until those aliens come and talk 0:04:15.280 --> 0:04:18.160 to us about the colors they see in the universe. 0:04:18.800 --> 0:04:21.240 Do you think they're a colored line too? Like Daniel, 0:04:21.600 --> 0:04:25.000 we think the answer to the universe is a light 0:04:25.040 --> 0:04:29.080 shade of lavender summer breeze. And then we would end 0:04:29.160 --> 0:04:30.440 up disagreeing about what that means. 0:04:30.640 --> 0:04:32.840 Yeah, I think whatever answer they have, my daughter will 0:04:32.839 --> 0:04:34.840 disagree with him. That's how I raised her. 0:04:36.000 --> 0:04:38.360 Let's not put her in the greeting committee. 0:04:38.440 --> 0:04:40.279 I think we agree on that Oh my gosh. Yes, 0:04:40.480 --> 0:04:42.720 let's not send Daniel's children to meet the aliens. 0:04:43.839 --> 0:04:47.120 Yeah, unless they start an intergalactic war. 0:04:49.200 --> 0:04:51.240 Maybe the colors are sacred to them, and if Hazel 0:04:51.279 --> 0:04:54.160 disagrees about what's purple and what's red, she's going to 0:04:54.200 --> 0:04:55.039 really piss them off. 0:04:55.400 --> 0:04:58.520 Yeah, or they might disagree about the color hazel itself. 0:04:59.160 --> 0:05:02.080 That's right. Yeah, exactly why are. 0:05:02.000 --> 0:05:04.040 You called hazel if you're not the color of a 0:05:04.080 --> 0:05:07.560 hazel nut. That's it. Forget this human race. It doesn't 0:05:07.560 --> 0:05:08.080 make any sense. 0:05:08.080 --> 0:05:09.720 It doesn't make any sense. You know, we named it 0:05:09.720 --> 0:05:11.680 her hazel before we knew her. But she does turn 0:05:11.680 --> 0:05:14.560 out to light the color hazel and hazel nuts, so 0:05:15.120 --> 0:05:15.640 there's a win. 0:05:15.880 --> 0:05:17.479 Yeah, but how do you know she's actually seen the 0:05:17.480 --> 0:05:21.200 color Hazel's hazel blind? 0:05:21.320 --> 0:05:22.480 M hazel blind. 0:05:22.520 --> 0:05:26.840 Wow, it's all hazey to her, it is. 0:05:27.160 --> 0:05:30.240 But we are fascinated by this concept of color, not 0:05:30.320 --> 0:05:32.720 just because it's such a visceral part of our experience, 0:05:33.160 --> 0:05:35.680 but because it's deeply connected to the physics of what's 0:05:35.680 --> 0:05:38.200 happening out there in the universe. It tells us something 0:05:38.200 --> 0:05:41.480 about how photons are wiggling, or how neutrinos are flying 0:05:41.520 --> 0:05:44.000 through the universe if you're willing to apply red and 0:05:44.040 --> 0:05:47.039 blue shifts to them as well. So this concept of color, 0:05:47.120 --> 0:05:49.279 what we see, what's out there in the universe, it's 0:05:49.440 --> 0:05:52.799 very confusing but also very illuminating about how the universe 0:05:52.880 --> 0:05:53.680 actually works. 0:05:54.160 --> 0:05:56.039 Yeah, there's a lot of physics in light and in 0:05:56.120 --> 0:05:58.680 all the colors. But then, as you said, it gets 0:05:58.680 --> 0:06:01.440 filtered through our eyes and our brains, and sometimes what 0:06:01.480 --> 0:06:04.599 we see is not quite what's out there, and maybe 0:06:05.160 --> 0:06:07.920 there might be things out there that are maybe impossible 0:06:08.040 --> 0:06:09.600 for us to experience. 0:06:09.800 --> 0:06:11.919 Well, that's right. We know that there are frequencies of 0:06:12.040 --> 0:06:15.200 light the humans can never experience, but are there also 0:06:15.480 --> 0:06:17.680 colors that are impossible to see? 0:06:17.839 --> 0:06:20.000 So to the end podcast, we'll be tackling the question 0:06:25.200 --> 0:06:27.600 what is an impossible color? 0:06:28.160 --> 0:06:29.919 It sounds like a job for Tom Cruise. 0:06:30.279 --> 0:06:32.200 Dunt dunt dan da dunt dun. 0:06:34.080 --> 0:06:36.400 This color will self destruct after you view it. 0:06:36.520 --> 0:06:42.400 We need a movie in which Tom Cruise is a physicist. Yeah, 0:06:42.400 --> 0:06:43.719 I mean he'd have to wear a lot of like 0:06:43.760 --> 0:06:46.760 wigs and prosthetics. Of course, he can't look like Tom Cruise. 0:06:47.960 --> 0:06:49.839 Yeah, he's too sexy to be a physicist. Is that 0:06:49.839 --> 0:06:53.280 what you're saying? I didn't say that he violates some 0:06:53.400 --> 0:06:54.200 physical law. 0:06:55.200 --> 0:06:56.000 He's too orange. 0:06:56.440 --> 0:06:58.960 He's definitely very physical, even if he's not a physicist, 0:06:59.120 --> 0:07:00.320 Right he doesn't. 0:07:00.480 --> 0:07:02.719 Yeah, that's right. Yeah. I wonder if he would do 0:07:02.800 --> 0:07:05.200 his own stunts in a physics movie, Like would you 0:07:05.240 --> 0:07:07.839 actually sit on the couch all day? I mean, that's 0:07:08.440 --> 0:07:10.400 it's probably more dangerous and jumping off a cliff. 0:07:10.600 --> 0:07:13.640 Then you put all those professional nap stunters out of work. 0:07:13.880 --> 0:07:16.320 You can just take naps on film as a wait. 0:07:16.320 --> 0:07:18.280 Wait, wait, that's a career. I can be a stunt 0:07:18.360 --> 0:07:19.760 napper exactly. 0:07:20.360 --> 0:07:21.800 Oh man, there's a career for everything. 0:07:21.800 --> 0:07:23.560 They're doing it all this time for free. Daniel. 0:07:23.920 --> 0:07:28.040 You know that the sign of an advanced civilization is specialization, right, 0:07:28.600 --> 0:07:31.600 And I think once we've achieved stunt napping, we've reached 0:07:31.640 --> 0:07:34.640 the pinnacle of civilizations. The aliens will be impressed. 0:07:35.000 --> 0:07:39.720 Oh, they might even hire us to nap for them. 0:07:39.840 --> 0:07:40.320 Well there's a. 0:07:40.320 --> 0:07:42.440 Twist ending, but yeah, this is an interesting question, the 0:07:42.480 --> 0:07:44.680 idea that there might be colors out there that are 0:07:44.800 --> 0:07:49.720 impossible to create, to experience, to see, to generate what 0:07:49.800 --> 0:07:51.280 side of the color spectrum. 0:07:50.880 --> 0:07:54.480 Are we Yeah, it's a complicated question. Because color is 0:07:54.520 --> 0:07:57.840 intimately connected with frequency, and we think about it as 0:07:57.880 --> 0:08:01.320 controlled by light, but really it's something inside our minds, 0:08:01.720 --> 0:08:04.960 it's something generated by our brain. It's an experience, and 0:08:05.000 --> 0:08:07.000 the colors you experience in the end come from the 0:08:07.040 --> 0:08:10.320 signals that travel up the optic nerve, which are not physical. 0:08:10.360 --> 0:08:13.800 They're just interpreted by your brain. And so it's interesting 0:08:13.800 --> 0:08:16.160 to think about whether there are colors that cannot be 0:08:16.200 --> 0:08:17.960 described by those signals. 0:08:18.200 --> 0:08:20.920 Oh boy, is this going to get into philosophy, Daniel, Like, 0:08:21.000 --> 0:08:22.560 what colors can a bat see? 0:08:24.760 --> 0:08:26.800 That's actually a great idea for paper. I'm gonna write 0:08:26.800 --> 0:08:28.040 that when we're done with this episode. 0:08:28.480 --> 0:08:30.000 Yeah, what color is your bad wing? 0:08:30.280 --> 0:08:33.439 Everything in the end is philosophy if you care about 0:08:33.440 --> 0:08:35.839 what it means. Right, So if you're going to answer 0:08:35.840 --> 0:08:38.760 the question what does that mean anyway? Then yeah, you're 0:08:38.760 --> 0:08:40.120 getting into philosophy. 0:08:40.360 --> 0:08:43.240 That sounds like a philosophical statement in itself, Daniel. 0:08:43.240 --> 0:08:44.920 The philosophy of philosophy. 0:08:45.200 --> 0:08:50.199 Yeah, you can get a phphphd in recursive philosophy in 0:08:50.200 --> 0:08:53.880 computer science philosophical puzzles well, as usually. We were wondering 0:08:53.880 --> 0:08:56.040 how many people had thought about this question of what 0:08:56.160 --> 0:08:58.920 is an impossible color, and so as usual, Daniel went 0:08:58.960 --> 0:09:01.560 out there to the Internet to ask people this question. 0:09:02.040 --> 0:09:04.480 Thanks very much to everybody who answers these questions for 0:09:04.520 --> 0:09:06.640 the podcast. If you would like to hear your voice 0:09:06.679 --> 0:09:09.760 on future episodes, please write to me two questions at 0:09:09.800 --> 0:09:11.320 danielan Jorge dot com. 0:09:11.480 --> 0:09:13.240 So think about it for a second. What do you 0:09:13.320 --> 0:09:16.880 think is an impossible color? Here's what people had to say. 0:09:17.520 --> 0:09:20.439 So, color is just a construct of our brain decoding 0:09:20.440 --> 0:09:25.280 the frequency of electiation. If you think about it and 0:09:25.440 --> 0:09:28.679 imagine our rods and cones were tuned a little wider 0:09:28.800 --> 0:09:32.920 and we could actually see an infrared and ultraviolet, and 0:09:33.040 --> 0:09:36.520 colors we can't see would be associated with those frequencies. 0:09:37.280 --> 0:09:40.480 So I guess every color associated with low frequency radio 0:09:41.200 --> 0:09:44.079 all the way to gamma rays would be impossible colors. 0:09:44.880 --> 0:09:48.080 If color is just how we perceive different wavelengths of light, 0:09:48.200 --> 0:09:51.040 and light can be in a huge range of wavelengths. 0:09:51.960 --> 0:09:54.280 It has something to do with the limits of the 0:09:54.320 --> 0:09:59.640 wavelength approaching either zero or infinity, where suddenly color doesn't 0:09:59.679 --> 0:10:01.000 make any sense anymore. 0:10:02.280 --> 0:10:08.160 An impossible color all very interesting. I'm going to say 0:10:08.480 --> 0:10:14.720 some sort of combination of spectral outputs that are that 0:10:14.880 --> 0:10:19.040 is a different spectral resolution than what our the receptors 0:10:19.040 --> 0:10:22.440 of our eyes are able to something to do with 0:10:22.640 --> 0:10:23.640 color metamerism. 0:10:25.120 --> 0:10:28.439 The interesting answers. I feel like nobody pitched the idea 0:10:28.480 --> 0:10:31.959 that maybe it's a color that's made out of plant based. 0:10:32.040 --> 0:10:34.800 Proteins vegan colors. 0:10:34.880 --> 0:10:40.960 Wow, yes, No, no animals or creatures were harmed in 0:10:41.000 --> 0:10:41.920 the making of this color. 0:10:44.240 --> 0:10:46.880 I can't even imagine a way you might harm an 0:10:46.960 --> 0:10:49.160 animal to make a color you're talking about, like, oh, 0:10:49.200 --> 0:10:51.320 let's see red, We're going to spill something's blood. Like 0:10:51.360 --> 0:10:54.040 it seems pretty unnecessary. 0:10:53.800 --> 0:10:57.560 I think, Daniel, you just don't have this strong enough imagination. 0:10:59.760 --> 0:11:02.280 But there are colors that are based on or traditionally 0:11:02.280 --> 0:11:05.000 there are dyes that are based on like insects, like 0:11:05.840 --> 0:11:06.680 insect juice. 0:11:07.080 --> 0:11:09.120 Oh yeah, okay, interesting, But. 0:11:09.080 --> 0:11:11.640 I don't know how vegans draw that line. 0:11:11.720 --> 0:11:13.199 You know, we're gonna have to have some of them 0:11:13.200 --> 0:11:14.520 on the podcast to answer the question. 0:11:15.080 --> 0:11:18.360 Yeah, sounds like good question for Katie. All right, well, 0:11:18.400 --> 0:11:21.800 let's dig into this question of what an impossible color is. 0:11:21.960 --> 0:11:24.760 Whether it means we can't see it, we can't make it, 0:11:24.760 --> 0:11:27.400 it can't exist in the universe. Let's figure it out. 0:11:27.640 --> 0:11:30.240 So you know, what are the basics of light and color? 0:11:30.480 --> 0:11:33.120 Yeah, so let's start outside the human brain before we 0:11:33.120 --> 0:11:35.960 get into like signal processing and all that stuff, and 0:11:36.080 --> 0:11:39.200 just begin with light. Right, Light we know is made 0:11:39.240 --> 0:11:42.920 of electromagnetic fields. There are ripples in electromagnetic fields, So 0:11:43.200 --> 0:11:44.880 we have electrical fields that can be made by like 0:11:44.920 --> 0:11:48.120 electrons and magnetic fields that have made my magnets. And 0:11:48.320 --> 0:11:50.720 light is a coupling of the electric fields and the 0:11:50.760 --> 0:11:55.000 magnetic fields together. Electric fields can induce magnetic fields, magnetic 0:11:55.000 --> 0:11:57.760 fields can induce electric fields. Light is like this perfect 0:11:57.800 --> 0:12:00.600 little packet where it's slashing back and forth between electric 0:12:00.600 --> 0:12:04.079 fields and magnetic fields in amazing harmony, and they can 0:12:04.080 --> 0:12:07.320 propagate through the universe, this little oscillation of the fields. 0:12:07.720 --> 0:12:10.640 And these oscillations have frequencies that have a wavelength, they 0:12:10.679 --> 0:12:14.280 have a frequency that relates to their energy. So if 0:12:14.280 --> 0:12:16.040 you have a beam of light, for example, coming out 0:12:16.040 --> 0:12:18.800 of a flashlight, it's actually made out of little photons, 0:12:18.800 --> 0:12:21.880 and each photon has a specific energy which has a 0:12:21.920 --> 0:12:26.280 specific wavelength and a specific frequency. So that's what light is, right, 0:12:26.440 --> 0:12:27.839 these packets of photons. 0:12:27.880 --> 0:12:29.840 So I have this laser and I'm shooting it, and 0:12:29.880 --> 0:12:32.360 there are photons coming out of it, and each photon 0:12:32.600 --> 0:12:35.400 is like a wiggle in the electromagnetic field. Is that 0:12:35.440 --> 0:12:35.840 what it is? 0:12:36.000 --> 0:12:39.040 Yeah, each photon is a wiggle in the electromagnetic field. 0:12:39.120 --> 0:12:41.319 But it's not a wiggle that's like propagating, like if 0:12:41.320 --> 0:12:44.120 I throw a pebble in a pond. It's not spreading 0:12:44.160 --> 0:12:46.280 out there like that, right, Like in a laser. These 0:12:46.280 --> 0:12:47.680 things are going in a straight line. 0:12:47.800 --> 0:12:49.760 These things are going in a straight line. And we 0:12:49.880 --> 0:12:53.120 just did a really fun but very confusing episode about 0:12:53.160 --> 0:12:54.720 how long is the photon? And if you didn't listen 0:12:54.760 --> 0:12:55.400 to that one, I. 0:12:55.360 --> 0:12:57.040 Was going to listen to it, but it's a little long. 0:13:00.000 --> 0:13:00.840 I'm not a light topic. 0:13:01.760 --> 0:13:04.079 And that tells you that real photons out there in 0:13:04.120 --> 0:13:06.920 the universe are a little packets. They have a length 0:13:07.040 --> 0:13:09.839 that's determined by the spread of the frequency. So in 0:13:09.920 --> 0:13:12.600 a sort of idealized sense, you can imagine every photon 0:13:12.640 --> 0:13:15.400 has exactly one frequency. It's like a pure little packet 0:13:15.440 --> 0:13:19.160 of one energy, one wavelength, one frequency. But that's actually 0:13:19.200 --> 0:13:21.760 mathematically very confusing because if it was like that, it 0:13:21.800 --> 0:13:24.480 would be everywhere in the universe. And so to build 0:13:24.559 --> 0:13:26.920 up a little packet that actually moves through the universe 0:13:26.920 --> 0:13:30.280 a little blob that stays together and flies through space. 0:13:30.520 --> 0:13:32.720 You have to have a little bundle of frequencies, so 0:13:33.160 --> 0:13:35.480 you know, blue photon is like a little spread of 0:13:35.600 --> 0:13:38.320 various blue frequencies, and a red photon is a little 0:13:38.360 --> 0:13:42.240 packet of a handful of differently red frequencies. 0:13:42.320 --> 0:13:44.199 And they're all going at the same speed, which is 0:13:44.240 --> 0:13:44.839 the speed of light. 0:13:45.160 --> 0:13:47.520 Yes, exactly, they all got the same speed even though 0:13:47.559 --> 0:13:50.040 they have a different wavelength and a different frequency, and 0:13:50.080 --> 0:13:52.320 the speed of light is the same across the spectrum. 0:13:52.559 --> 0:13:54.760 That's at least in our current theory. There are theories 0:13:54.760 --> 0:13:58.440 of physics like rainbow gravity, where different frequencies travel at 0:13:58.440 --> 0:14:01.120 different speeds and you get like effects around the edges 0:14:01.120 --> 0:14:03.000 of black holes, but are in their current theory physics, 0:14:03.040 --> 0:14:05.800 And according to all of our measurements, every photon travels 0:14:05.840 --> 0:14:06.560 at the same. 0:14:06.320 --> 0:14:10.600 Speed, and the spectrum of frequencies that light can have, 0:14:10.720 --> 0:14:14.200 it's basically one dimensional, right, Like there's only one knob 0:14:15.280 --> 0:14:16.440 for the frequency of light. 0:14:16.720 --> 0:14:18.560 Yeah, if you're going to think about a photon. 0:14:18.360 --> 0:14:21.080 From zero to infinity, hmm, But it's just a line, 0:14:21.160 --> 0:14:22.800 and if you were to draw a plot of it. 0:14:23.040 --> 0:14:25.200 Yes, exactly, it's one dimensional. It's a great way to 0:14:25.200 --> 0:14:28.200 think about it. And it is infinitely dense, right, there's 0:14:28.240 --> 0:14:31.400 an infinite number of frequencies there. We think of these 0:14:31.400 --> 0:14:33.920 things as like, oh, they're quantum mechanical, so it must 0:14:34.000 --> 0:14:37.200 be discrete, must be broken up into chunks, right, But 0:14:37.240 --> 0:14:40.400 the reality is that free objects, even free electrons, are 0:14:40.440 --> 0:14:43.800 not quantized in their energy levels. They're quantized in the 0:14:43.960 --> 0:14:46.560 number of photons. Like you can't have one point seven 0:14:46.600 --> 0:14:49.720 photons or two point two seven photons. You can have 0:14:49.760 --> 0:14:53.200 one or two or nineteen. But each photon can have 0:14:53.320 --> 0:14:56.440 any energy. There's no limitation, there's no quantitization, there's no 0:14:56.520 --> 0:14:59.560 descritization of the energy spectrum. But yes, it is one 0:14:59.600 --> 0:15:00.400 dimension all. 0:15:00.840 --> 0:15:03.240 That you know of though, right, Like, is it possible 0:15:03.240 --> 0:15:05.240 that maybe frequency is quantized as well. 0:15:05.600 --> 0:15:08.120 Yeah, in our current theory that's the case. There are 0:15:08.280 --> 0:15:11.760 theories of quantum gravity in which like space is pixelated, 0:15:11.960 --> 0:15:14.600 which would make like a minimum wavelength, and in that 0:15:14.760 --> 0:15:18.000 case every distance is quantized. In our current theories, there's 0:15:18.000 --> 0:15:20.960 no minimum frequency, but that doesn't actually really make sense 0:15:21.200 --> 0:15:24.280 below like the plank length, where every photon would like 0:15:24.320 --> 0:15:27.280 collapse into a black hole anyway, So it only really 0:15:27.320 --> 0:15:30.280 applies up to a very very high energy, but much 0:15:30.320 --> 0:15:31.760 higher than we could probe today. 0:15:32.040 --> 0:15:33.960 All right, So that's the physics of it. Now let's 0:15:33.960 --> 0:15:37.320 get into the biology of it. So when these photons 0:15:37.360 --> 0:15:41.000 hit our eyes, they create and experience in our brains. 0:15:41.280 --> 0:15:44.880 Yeah, I think there's one step before that, which is reflection. Like, 0:15:45.080 --> 0:15:48.000 let's imagine we're looking at a banana, right, why do 0:15:48.040 --> 0:15:50.800 we see the banana as yellow? We see the banana 0:15:50.840 --> 0:15:54.120 as yellow because white light hits the banana from the sun, 0:15:54.520 --> 0:15:56.560 and then some of it is absorbed and some of 0:15:56.600 --> 0:15:59.280 it is reflected. You start with almost every frequency of 0:15:59.360 --> 0:16:01.920 light you can see the banana, But then the banana 0:16:01.960 --> 0:16:04.640 has chemicals in it and atoms, and those atoms prefer 0:16:04.720 --> 0:16:07.720 to absorb some colors and not absorb other colors. And 0:16:07.760 --> 0:16:11.040 so when you see yellow as banana, that means that 0:16:11.080 --> 0:16:14.040 the wavelength of light that is being reflected is a 0:16:14.080 --> 0:16:16.720 specific band in this case, like between five hundred and 0:16:16.760 --> 0:16:20.120 seventy and five hundred and eighty nanometers. So you see 0:16:20.160 --> 0:16:22.560 something as red, it's not because it's like absorbing the 0:16:22.640 --> 0:16:25.440 red light, right, It's because it's reflecting the red light 0:16:25.480 --> 0:16:29.000 and absorbing everything else. But then yeah, it hits your eyeball, 0:16:29.000 --> 0:16:31.480 and those photons with a certain frequency are now going 0:16:31.520 --> 0:16:33.880 to be interacted with by your eye, which is like 0:16:33.960 --> 0:16:35.760 basically little observational device. 0:16:36.160 --> 0:16:39.560 But wait, the banana, So the banana absorbs all frequencies 0:16:39.680 --> 0:16:42.760 except maybe the kinds that are my brain will interpret 0:16:42.800 --> 0:16:43.360 as yellow. 0:16:44.000 --> 0:16:47.200 Yeah, not all frequencies, but all visible ones. Right, banana 0:16:47.200 --> 0:16:50.840 can't necessarily absorb all X rays and gamma rays or infrared, 0:16:51.080 --> 0:16:54.000 but in the visible spectrum and again, and not even 0:16:54.040 --> 0:16:55.960 all of that, right, Like you see it yellow because 0:16:56.000 --> 0:16:58.880 it's dominant in the yellow. It's never like intense and 0:16:58.960 --> 0:17:02.200 yellow and zero in every other frequency. You know, it just. 0:17:02.160 --> 0:17:04.639 Peaks unless it's like a perfect banana. Like, is it 0:17:04.680 --> 0:17:07.679 possible to create a perfect banana that only reflects like 0:17:07.840 --> 0:17:09.600 one frequency of yellow. 0:17:09.960 --> 0:17:12.520 If you make a shade which only reflects one frequency 0:17:12.520 --> 0:17:15.160 of yellow, I think Hazel would call that perfect banana. 0:17:15.280 --> 0:17:16.719 That is a nice name for a yellow. 0:17:18.640 --> 0:17:20.040 Exact banana, yes. 0:17:20.440 --> 0:17:22.560 Exact scientific banana. 0:17:22.680 --> 0:17:25.080 Okay, So there's a reflection and also I mean there's 0:17:25.080 --> 0:17:29.120 filtering too. But while we're talking about it, like it right, 0:17:29.160 --> 0:17:31.560 like if I have rose colored glasses, the world looks 0:17:31.640 --> 0:17:34.879 rose to me. Because it's filtering out all frequencies except 0:17:34.920 --> 0:17:36.760 the ones that I see is rose. 0:17:36.960 --> 0:17:40.200 Yeah, exactly, it's filtering. There's a reflection. All this affects 0:17:40.280 --> 0:17:43.119 the frequencies that actually hit your eyeball. But I hear 0:17:43.160 --> 0:17:44.840 a lot of confusion out there and the questions I 0:17:44.840 --> 0:17:47.520 get from listeners about what makes something a color, whether 0:17:47.520 --> 0:17:50.320 it's absorbing it or reflecting it, And so it's important 0:17:50.320 --> 0:17:52.680 to remember that the color is something that's in your 0:17:52.760 --> 0:17:55.200 eye depends on the light that hits your eyeball. You 0:17:55.200 --> 0:17:58.280 can only see something if it hits your eyeball. For example, 0:17:58.280 --> 0:18:00.520 if a photon was flying in front of you your face, 0:18:00.640 --> 0:18:03.199 you couldn't see it right. If it just flies past you, 0:18:03.200 --> 0:18:06.000 you don't see like a little glowing blob going through 0:18:06.040 --> 0:18:09.399 the universe. You imagine your visual perception is giving you 0:18:09.440 --> 0:18:12.480 an accurate description of everything that's out there in the universe, 0:18:12.760 --> 0:18:14.800 but you only see things that hit your eyeball. Photon 0:18:14.800 --> 0:18:17.640 that passes in front of you doesn't send any signals 0:18:17.680 --> 0:18:19.320 to you, so you don't see it right. 0:18:19.359 --> 0:18:21.040 Like if someone to my right shoots a laser to 0:18:21.080 --> 0:18:22.760 my left, I won't see it. It has to be 0:18:22.880 --> 0:18:24.879 they have to be shooting into my eye for me 0:18:24.960 --> 0:18:25.359 to see the. 0:18:25.359 --> 0:18:28.240 Laser, yeah, or it has to hit dust particles along 0:18:28.240 --> 0:18:31.159 the way or air and ionize that and make a 0:18:31.200 --> 0:18:33.920 glow or a reflection. Right, But a perfect laser in 0:18:34.000 --> 0:18:36.320 a vacuum you will not see until it slices your 0:18:36.320 --> 0:18:36.760 head open. 0:18:37.760 --> 0:18:41.320 The photons, ever, split into other photons. 0:18:41.440 --> 0:18:45.480 Photons can convert into electron positron pairs, which can then 0:18:45.520 --> 0:18:48.800 interact with other stuff, like including other photons, and do 0:18:48.920 --> 0:18:52.080 crazy stuff that differently could happen, and those could create 0:18:52.119 --> 0:18:54.760 other photons, So that can happen, but it's quantum mechanically 0:18:54.760 --> 0:18:57.399 pretty rare. If you pass a photon through a special 0:18:57.480 --> 0:19:00.520 kind of non linear crystal, it can split into two 0:19:00.640 --> 0:19:03.639 other photons. They use that for important experiments to like 0:19:03.800 --> 0:19:07.560