WEBVTT - Artificial Gravity: Cosmic Wheels and Hurtling Towers 0:00:03.040 --> 0:00:05.840 Welcome to Stuff to Blow your Mind from how Stuff 0:00:05.880 --> 0:00:14.239 Works dot com. Hey you welcome to Stuff to Blow 0:00:14.280 --> 0:00:16.520 your mind. My name is Robert Lamb and I'm Joe 0:00:16.600 --> 0:00:19.880 McCormick and Robert. I know that many times you must 0:00:19.880 --> 0:00:24.880 have imagined what life is like in a zero gravity environment, right, Oh? Yeah, 0:00:24.880 --> 0:00:27.760 I mean you can't help you. You You can't help thinking 0:00:27.760 --> 0:00:31.520 about it as you read about space exploration and engage 0:00:31.560 --> 0:00:34.400 with with various science fiction scenarios. What what would it 0:00:34.440 --> 0:00:38.480 be like to to float free, uh, inside of a capsule? Yeah? 0:00:38.520 --> 0:00:42.760 And people obviously imagine the very simple stuff, right, you know, 0:00:42.800 --> 0:00:44.640 floating from one end of the room to the other, 0:00:44.800 --> 0:00:47.360 not being able to walk normally, maybe fear that you 0:00:47.360 --> 0:00:50.640 would experience some motion sickness. You know, many, many people 0:00:50.680 --> 0:00:53.120 who go to space I think at least half I 0:00:53.159 --> 0:00:56.240 think is the number, experience some kind of space adaptation 0:00:56.920 --> 0:01:00.240 problems space sickness once they arrive. That might go way 0:01:00.240 --> 0:01:02.960 after some time. Yeah, Or you tend to focus on 0:01:03.280 --> 0:01:07.640 the amazing and the horrible ideas, like you know, for instance, 0:01:07.640 --> 0:01:10.640 how fun it would be to drink orange juice and 0:01:10.760 --> 0:01:14.039 space by chasing the globs around the capsule, or the 0:01:14.080 --> 0:01:18.040 more you know, they're definitely horrible or or almost horrible 0:01:18.080 --> 0:01:21.759 scenarios such as, of course, uh you know, the bone 0:01:21.760 --> 0:01:25.840 mass density loss, as well as the problem of trying 0:01:25.880 --> 0:01:27.800 to poop in a toilet. Right, I thought you were 0:01:27.800 --> 0:01:30.240 going to immediately go to using the bathroom. I was 0:01:30.319 --> 0:01:31.920 immediately going to go to the bathroom, And then I 0:01:31.920 --> 0:01:35.200 thought I should I should reference like the really pivotal 0:01:35.200 --> 0:01:39.240 problem here as opposed to just the one that is difficult. No, 0:01:39.319 --> 0:01:41.720 I mean, going to the bathroom isn't necessarily a big problem. 0:01:41.760 --> 0:01:44.400 You know, you it might not sound all that appealing 0:01:44.440 --> 0:01:47.840 to essentially poop into a vacuum cleaner but or bag. 0:01:48.160 --> 0:01:50.520 You know a lot of people maybe that's something they've 0:01:50.520 --> 0:01:54.240 always wanted to try out. It's not necessarily a horrible idea, 0:01:54.560 --> 0:01:57.360 but it will definitely be horrible. I don't know if 0:01:57.400 --> 0:01:59.920 you make a mistake in this process. Right, That's where 0:01:59.920 --> 0:02:02.960 the horror stories kick in, is when the the the 0:02:03.040 --> 0:02:07.080 super expensive space toilet malfunctions. The same thing, of course 0:02:07.200 --> 0:02:09.880 is true, well not exactly the same thing. A similar 0:02:09.919 --> 0:02:13.919 thing is true of you mentioned chasing orange juice globules 0:02:13.919 --> 0:02:17.600 with your mouth to hunt them down, but eating in space, 0:02:18.040 --> 0:02:20.800 I mean, we depend on gravity so much for a 0:02:20.800 --> 0:02:24.519 lot of our eating activity. Keeping food in a container. 0:02:24.800 --> 0:02:28.280 I mean, you just can't compose dishes in space. You've 0:02:28.280 --> 0:02:30.720 gotta again kind of like you poop into a bag. 0:02:30.760 --> 0:02:33.520 You've got to eat out of a bag um, or 0:02:33.600 --> 0:02:36.679 have something that's relatively solid and doesn't have crumbs that 0:02:36.720 --> 0:02:38.520 are going to get everywhere. I mean, can you think 0:02:38.520 --> 0:02:41.760 about trying to salt your food in space? You sort 0:02:41.800 --> 0:02:44.000 of need to like salt into a bag and shake 0:02:44.040 --> 0:02:45.960 it up or something. Yeah, or just have like a 0:02:46.000 --> 0:02:48.359 hot sauce packet that you you add into your own 0:02:48.440 --> 0:02:50.639 mouth afterwards. I feel like I could get buying a 0:02:50.760 --> 0:02:54.160 number of like bagged curries and whatnot. Yeah. Now, of course, 0:02:54.200 --> 0:02:57.800 another thing astronaut's report about zero gravity environments is that 0:02:57.919 --> 0:03:01.040 your sense of taste is all jam up, Like you 0:03:01.120 --> 0:03:03.839 can't taste things the way you normally would. And part 0:03:03.840 --> 0:03:06.400 of this probably has to do with the fluid redistribution 0:03:06.480 --> 0:03:09.000 in your body that leads your head and upper body 0:03:09.040 --> 0:03:12.520 to swell because you don't have the normal gravity pulling 0:03:12.520 --> 0:03:14.600 all the fluids in your body towards your feet, which 0:03:14.600 --> 0:03:19.520 your body is naturally trying to overcompensate for another gravity 0:03:19.560 --> 0:03:22.600 tidbit that that I always find fascinating is that I 0:03:22.600 --> 0:03:25.040 believe Mary Roach pointed this out in their book Packing 0:03:25.080 --> 0:03:29.519 from Mars. If you're in a microgravity zero gravity environment, 0:03:29.840 --> 0:03:33.440 your bladder doesn't fill up from the bottom up. It 0:03:33.480 --> 0:03:36.040 feels like in the center, right, It fills like all 0:03:36.080 --> 0:03:38.240 around towards the very center. So you don't realize that 0:03:38.320 --> 0:03:42.480 you need a urinate, uh, typically until you're absolutely about 0:03:42.560 --> 0:03:46.320 to burst, because because we have evolved to sense the 0:03:46.440 --> 0:03:49.600 to detect that the need for our own urination on 0:03:49.680 --> 0:03:52.240 a gravity invite, in a gravity environment, on a on 0:03:52.280 --> 0:03:55.080 a world with gravity, we are creatures of gravity. It 0:03:55.120 --> 0:03:57.960 reminds me of a piece of terminology I haven't really 0:03:58.000 --> 0:04:01.040 thought of since elementary school, but back and there would 0:04:01.040 --> 0:04:03.680 be a thing that would be like a p quote emergency. 0:04:04.360 --> 0:04:07.240 Remember the emergency. Yeah, well, I mean I guess if 0:04:07.240 --> 0:04:09.560 you have kids, there's such a thing as an emergency. Yeah. 0:04:09.560 --> 0:04:12.640 I have a five year old son, and so he 0:04:12.760 --> 0:04:16.160 has these where it's like suddenly it's super dire, like 0:04:16.279 --> 0:04:19.039 you have he has to run outside of the front 0:04:19.040 --> 0:04:21.800 doors closer to him, uh, you know, grabbing himself the 0:04:21.800 --> 0:04:24.240 whole time and going I gotta go pee and the 0:04:24.360 --> 0:04:27.360 immediately paying Um, this is the kind of thing adults 0:04:27.400 --> 0:04:32.039 tend not to experience unless perhaps you go into space. Right, 0:04:32.440 --> 0:04:36.160 So those are the the less dire things now you 0:04:36.200 --> 0:04:39.800 already alluded to. Of course, the deterioration of body tissues, 0:04:40.640 --> 0:04:44.279 loss of bone density, loss of muscle mass, and and 0:04:44.279 --> 0:04:47.560 and all the different negative consequences that happened to the 0:04:47.600 --> 0:04:52.080 body under zero gravity or microgravity conditions. These things can 0:04:52.080 --> 0:04:55.880 really stack up. And it's not a trivial effect. Astronauts 0:04:55.960 --> 0:04:59.599 have to exercise constantly when they're in microgravity environments. They've 0:04:59.600 --> 0:05:02.320 got a spend hours a day working out in these 0:05:02.360 --> 0:05:05.560 weird machines just to try to offset some of the 0:05:05.640 --> 0:05:08.279 damage that's being done to their bodies by the lack 0:05:08.480 --> 0:05:12.360 of gravity in their environment. And it's still not enough, 0:05:12.560 --> 0:05:14.600 all right, I mean, they still come back to back 0:05:14.640 --> 0:05:18.040 to Earth messed up, and they need time to really reacclimate. 0:05:18.080 --> 0:05:20.880 Hopefully they will eventually come back to something like full health. 0:05:21.400 --> 0:05:23.919 But but it's not good for you. Yeah, And and 0:05:23.960 --> 0:05:27.080 of course one of the problems is that uh, astronauts 0:05:27.040 --> 0:05:29.800 want to go back to space, so they're not necessarily 0:05:29.839 --> 0:05:33.520 going to be as forthcoming about the about how they're 0:05:33.520 --> 0:05:35.880 exactly feeling. Yeah, I guess that is a thing to 0:05:35.920 --> 0:05:38.960 worry about. You'd hope that they'd be accurately reporting how 0:05:39.000 --> 0:05:41.520 bad it is, but maybe they just they want to 0:05:41.520 --> 0:05:43.600 get back up there. Yeah, I mean that, that's that's 0:05:43.640 --> 0:05:46.280 what what I've I've heard is that generally speaking, and 0:05:46.360 --> 0:05:48.520 you don't go to space then and you're like, oh, 0:05:48.680 --> 0:05:51.720 that's enough of that. I'm good an astronaut. A person's 0:05:51.720 --> 0:05:54.760 worth their whole life to do this for not even 0:05:54.800 --> 0:05:56.479 just to do this, but for the chance of doing this. 0:05:56.600 --> 0:05:58.279 Of course they're gonna want to go back. So my 0:05:58.440 --> 0:06:01.479 question is, why don't the people who run the I 0:06:01.760 --> 0:06:03.640 S S. I don't know whoever they are, NASA, I 0:06:03.640 --> 0:06:08.480 guess maybe not NASA space agencies around the world. Why 0:06:08.520 --> 0:06:11.520 don't the people who run our space stations just take 0:06:11.560 --> 0:06:14.799 advantage of the Holtzman effect and put some gravity plating 0:06:14.839 --> 0:06:16.680 in there so that you can walk around like a 0:06:16.760 --> 0:06:19.440 normal Earth humans. A. Yeah, so yeah, you're so you're 0:06:19.480 --> 0:06:23.240 drawing in both Star Trek and Dune here, but they're 0:06:23.279 --> 0:06:26.440 they're both prime examples because they're straight into the blender. 0:06:28.240 --> 0:06:30.800 Because this is uh, this is one of the key 0:06:30.839 --> 0:06:34.880 aspects of our science fiction when it comes to gravity 0:06:34.960 --> 0:06:37.760 or lack of gravity and space, they're basically three models. 0:06:38.120 --> 0:06:40.680 Either you're gonna you're gonna try and go hard science 0:06:41.000 --> 0:06:44.040 and have some sort of an artificial gravity scenario like 0:06:44.080 --> 0:06:46.000 some of the realistic scenarios we're going to discuss in 0:06:46.040 --> 0:06:49.919 this podcast. You're gonna just go you know, micro gravity 0:06:50.040 --> 0:06:52.400 zero G and have people floating around, which of course 0:06:52.640 --> 0:06:55.600 can be difficult from a special effects standpoint. Or you're 0:06:55.600 --> 0:06:58.360 gonna go space wizards. Yeah, you're just gonna go magic 0:06:58.480 --> 0:07:02.599 artificial gravity and just say hey, we let's star trek. 0:07:02.680 --> 0:07:07.159 We have gravity plates in the floor. Of course there's gravity. Uh, 0:07:07.400 --> 0:07:09.960 it's the and in in in Dune you have the 0:07:10.200 --> 0:07:13.920 the Holtzman effect generated by the Holtzmann field generator, and 0:07:14.080 --> 0:07:17.280 Herbert never explain exactly what it was or how it worked, 0:07:17.560 --> 0:07:20.160 but it allowed for the generation of anti gravity faster 0:07:20.240 --> 0:07:24.520 than light travel, personal shields, artificial gravity on ships, you know, 0:07:24.560 --> 0:07:26.440 all the things you need to sort of go ahead 0:07:26.440 --> 0:07:31.560 and establish your interstellar uh empire, and then tell the 0:07:31.560 --> 0:07:33.360 stories you want to tell. You know, I'm okay with 0:07:33.400 --> 0:07:37.120 that because in lots of science fiction stories, essentially they're 0:07:37.120 --> 0:07:40.160 trying to tell a character drama or it's a fantasy 0:07:40.240 --> 0:07:43.520 story set in space. I don't need all science fiction 0:07:43.560 --> 0:07:46.560 to be hard science fiction, but I really do appreciate 0:07:46.600 --> 0:07:49.280 hard science fiction that tries to take the physics that 0:07:49.320 --> 0:07:52.960 we know seriously. This does not. But that's okay, you know, 0:07:53.000 --> 0:07:55.200 that's doing its own thing. Yeah. I mean, Herbert had 0:07:55.240 --> 0:07:57.080 areas that he was definitely going to focus in on, 0:07:57.160 --> 0:08:02.720 such as ecological issues, philosophical, religious, cultural issues, and of 0:08:02.760 --> 0:08:06.240 course this the drama that is especially seen in the 0:08:06.280 --> 0:08:09.480 first book. So I kind of some slack. I'm fine 0:08:09.480 --> 0:08:12.680 with some magic anti gravity. Now, in terms of sci 0:08:12.720 --> 0:08:15.400 fi properties that do take it really seriously. What are 0:08:15.440 --> 0:08:17.120 What are a few films that come to mind? Well, 0:08:17.160 --> 0:08:19.760 of course you you immediately think of two thousands, one 0:08:19.760 --> 0:08:23.480 of Space Odyssey. Now that's got multiple spacecraft. There's a 0:08:23.520 --> 0:08:26.640 space station and there's a spacecraft that both use something 0:08:26.720 --> 0:08:29.960 we're going to talk about later in the episode rotational 0:08:30.720 --> 0:08:35.559 UH structures for centripetal force driven or centrifical, centrifugal or 0:08:35.600 --> 0:08:40.240 centripetal force driven artificial gravity scenarios. Also, there is a 0:08:40.400 --> 0:08:44.120 good artificial gravity ship in the Martian UH, and I 0:08:44.120 --> 0:08:46.439 remember I think there's one in a space station and 0:08:46.520 --> 0:08:49.600 Interstellar isn't there. Yes, I do believe I remember the 0:08:49.800 --> 0:08:53.679 spinning situation. And I also want to point out James S. A. 0:08:53.800 --> 0:08:57.680 Corey's Expanse series, both the books and the sci fi 0:08:57.720 --> 0:09:01.160 TV show, which which does I think a really good 0:09:01.240 --> 0:09:07.520 job of going after from near future interplanetary culture and technology. 0:09:07.840 --> 0:09:11.640 And it's also the only sci fi property that I 0:09:11.679 --> 0:09:15.360 can think of that that actually explores one of the 0:09:15.480 --> 0:09:18.280 anti gravity schemes we're gonna we're gonna be discussing today 0:09:18.400 --> 0:09:22.400 linear acceleration. Well, linear acceleration. I can see why that's 0:09:22.440 --> 0:09:25.679 limited because it has sort of limited applicability if you're 0:09:25.679 --> 0:09:28.520 going to try to be real about like it only 0:09:28.520 --> 0:09:31.480 works in certain types of ships doing certain types of 0:09:31.520 --> 0:09:34.520 things to a certain extent. We can we can chat 0:09:34.559 --> 0:09:37.840 about this, this this later. Okay, we'll correct me. Well, 0:09:37.840 --> 0:09:39.760 I don't know, but it's not really correction. But I 0:09:39.760 --> 0:09:43.280 think one of the problems is that linear acceleration model 0:09:43.920 --> 0:09:49.400 calls for a spaceship that is not a seagoing vessel 0:09:49.520 --> 0:09:53.880 transported into space, because, as I said before the program, 0:09:53.920 --> 0:09:55.320 I think a lot of our science fiction and our 0:09:55.360 --> 0:09:58.839 sci fi ships are essentially seagoing vessels and tales of 0:09:58.880 --> 0:10:02.240 seagoing vessels and sea and Captain's uh taken from Earth 0:10:02.280 --> 0:10:05.320 and transposed into space. I mean that was basically Gene 0:10:05.360 --> 0:10:08.760 Roddenberry's a whole deal with Star Trek. That was m 0:10:09.160 --> 0:10:11.319 was the Master and Commander books that he wasn't No, 0:10:11.480 --> 0:10:15.280 it was a different one. Um. I can't remember that 0:10:15.360 --> 0:10:18.160 the series offhand. But anyway, he was inspired by by 0:10:18.160 --> 0:10:25.319 literary tales of of of adventurous humans at sea. Uh No, well, 0:10:25.320 --> 0:10:26.800 maybe I don't know. Well, I guess the Wrath of 0:10:26.840 --> 0:10:30.120 con is yeah, from Hell's Haired I staff at the right. 0:10:30.840 --> 0:10:33.200 But it's it's more difficult with linear acceleration because you 0:10:33.200 --> 0:10:35.280 have to you have to take that concept of an 0:10:35.280 --> 0:10:38.200 Earth vessel and you really have to literally turn it 0:10:38.200 --> 0:10:40.400 on its side. You have to think instead of a 0:10:40.400 --> 0:10:42.800 ship going from port to port and stopping, you have 0:10:42.840 --> 0:10:46.160 to think about long, continuous journeys. But we'll get into 0:10:46.200 --> 0:10:48.440 all that in a bit. Okay, Well, I guess we 0:10:48.440 --> 0:10:50.880 should first just take a real quick look at what 0:10:51.080 --> 0:10:55.200 is the problem with artificial gravity, with generating gravity and space. 0:10:55.200 --> 0:10:58.679 Why can't you just do it? Well, I mean, so 0:10:58.720 --> 0:11:01.800 gravity is something that is a field generated by generally 0:11:01.800 --> 0:11:04.680 we think of it as mass. It's generated by the 0:11:04.720 --> 0:11:07.840 stuff in the universe, energy and mass, you know, much 0:11:07.880 --> 0:11:10.920 more by matter that has mass. So we all know 0:11:11.000 --> 0:11:14.160 that objects that have mass have a mutual attractive force. 0:11:14.240 --> 0:11:16.880 They tend to attract one another. And you know, we've 0:11:16.920 --> 0:11:19.280 known this for a long time. It was the laws 0:11:19.280 --> 0:11:22.520 of gravitation were to a certain extent well explained by 0:11:22.600 --> 0:11:25.880 Newton in the seventeenth century, and he basically described the 0:11:25.920 --> 0:11:28.520 laws of gravitation in a way that that makes sense 0:11:28.559 --> 0:11:30.559 for most of the stuff we're going to be looking at, 0:11:30.920 --> 0:11:34.000 for planets, for spaceships, for things like that. Now. Of course, 0:11:34.559 --> 0:11:38.640 later Albert Einstein revolutionized our understanding of what gravity is 0:11:38.720 --> 0:11:41.400 by telling us that gravity is the curvature of space time, 0:11:41.920 --> 0:11:45.400 and that sort of matter tells spacetime how to curve, 0:11:45.920 --> 0:11:48.880 and that the curvature of spacetime tells matter how to move. 0:11:50.200 --> 0:11:52.599 So let's start with masks, and I think that's the 0:11:52.760 --> 0:11:55.840 that's that's the essential part. That's that's a pretty easy 0:11:55.840 --> 0:11:59.640 to understand here. So everything with mass, from a dust 0:11:59.679 --> 0:12:02.840 mote to a star, exerts a gravitational pull. The strength 0:12:02.880 --> 0:12:05.840 of the poll, however, increases with mass. And proximity to 0:12:05.880 --> 0:12:09.240 the object. So a smaller object can only attract another 0:12:09.360 --> 0:12:11.880 small object of it's nearby, but a large object can 0:12:11.880 --> 0:12:14.920 pull in objects from across the vast distance. And this 0:12:15.000 --> 0:12:18.400 is kind of this is key to the structure much 0:12:18.440 --> 0:12:20.160 of the structure of our of our universe. I mean, 0:12:20.160 --> 0:12:23.800 this is how accretion occurs, with little specks of space 0:12:23.920 --> 0:12:29.520 dust and gas forming together and snowballing into larger cosmic bodies. Yeah, 0:12:29.520 --> 0:12:31.960 I mean, this is how our solar system was created. 0:12:32.160 --> 0:12:35.560 Was the coalescing of objects by the force of gravity. 0:12:35.640 --> 0:12:39.640 Things are attracted to each other, eventually becoming stars, planets, 0:12:40.000 --> 0:12:43.520 all that. Yeah. And then Albert Einstein's general theory of 0:12:43.520 --> 0:12:45.960 relativity comes along and propose that the gravity is a 0:12:46.000 --> 0:12:48.959 curve in the fourth dimension of space time. And there's 0:12:48.960 --> 0:12:51.800 proof to back him up. Given sufficient mass, an object 0:12:51.800 --> 0:12:54.520 can cause an otherwise straight beam of light to curve. 0:12:55.040 --> 0:12:59.400 Astronomers called this effect gravitational lensing. Yeah, this was shown experimentally. 0:12:59.440 --> 0:13:02.319 It was one of the fir speak experimental proofs of 0:13:02.720 --> 0:13:06.080 Einstein's theory of relativity is that you could see light 0:13:06.160 --> 0:13:10.120 from stars passing behind the Sun bending as it came 0:13:10.320 --> 0:13:12.920 right around the Sun. So you know, if you could 0:13:13.160 --> 0:13:15.760 have a solar eclipse and shield out the light from 0:13:15.800 --> 0:13:18.199 the Sun, you could see stars in the background being 0:13:18.320 --> 0:13:20.719 warped by the Sun's gravity as the beams of light 0:13:20.760 --> 0:13:24.360 passed close to our Sun. Yeah, and similarly, the less 0:13:24.360 --> 0:13:26.960 gravity there is, the slower time passes. And this is 0:13:26.960 --> 0:13:31.080 a phenomenon is gravitational time dilation, and this is this 0:13:31.120 --> 0:13:32.680 is the less key to what we're talking about. But 0:13:32.720 --> 0:13:35.840 it just drives home like the place of gravity, uh 0:13:35.880 --> 0:13:38.520 in our universe. Yeah, it sounds this is one of 0:13:38.559 --> 0:13:41.000 those things that sounds like fantasy, but it's absolutely true. 0:13:41.040 --> 0:13:43.559 And you saw that We mentioned the movie Interstellar earlier. 0:13:43.600 --> 0:13:46.000 There's actually, Uh, there are a couple of great scenes 0:13:46.040 --> 0:13:48.360 and the demonstrate this where they go down to a 0:13:48.400 --> 0:13:52.920 planet with an incredibly high gravitational pull and uh, while 0:13:52.960 --> 0:13:55.680 they're down there on the planet, much less time passes 0:13:55.720 --> 0:13:57.840 for the people on the planet than passes for people 0:13:57.920 --> 0:14:02.040 in orbit farther away. Yeah. As a physicist Paul Davies 0:14:02.120 --> 0:14:04.880 points out, time runs a little bit faster in space 0:14:04.880 --> 0:14:06.680 than it does down on Earth. It runs a little 0:14:06.720 --> 0:14:08.800 faster on the roof than it does in the basement, 0:14:09.160 --> 0:14:12.480 and that's a measurable effect. Then's the basics on gravity. 0:14:13.400 --> 0:14:17.040 But then there's also this additional area of quantum gravitation 0:14:17.600 --> 0:14:20.720 and the idea that that there is a there's a 0:14:20.800 --> 0:14:25.240 hypothetical particle, the graviton, which in theory could cause optics 0:14:25.240 --> 0:14:27.520 to be attracted to one another. Yeah, and this would 0:14:27.520 --> 0:14:30.760 be the mediating particle of the force of gravity, in 0:14:30.760 --> 0:14:33.600 the same way you've got like the electromagnetic force, the 0:14:33.680 --> 0:14:37.760 mediating particle there is the photon. Hypothetically you'd have some 0:14:37.920 --> 0:14:41.880 mediating particle delivering the force of gravity. But we've never 0:14:41.880 --> 0:14:44.560 seen gravitons in the universe. Right. This is the this 0:14:44.640 --> 0:14:48.680 whole hypothesis comes together because quantum theory, to refresh, addresses 0:14:48.760 --> 0:14:51.960 how the universe works at the smallest subotonic levels, and 0:14:52.000 --> 0:14:57.360 the resulting model here does not explain gravity. So gravitons 0:14:57.720 --> 0:15:00.640 and the theory of quantum gravity isn't a attempt to 0:15:00.840 --> 0:15:05.120 reconcile general relativity with quantum theory. It's a basically an 0:15:05.160 --> 0:15:08.160 attempt to patch up a hole in the standard model 0:15:08.240 --> 0:15:11.880 of particle physics, which cannot explain gravity. Now, the last 0:15:11.920 --> 0:15:14.960 time I read seriously about gravitons was a few years ago. 0:15:15.000 --> 0:15:18.600 I wonder if any recent experiments in our particle colliders 0:15:18.640 --> 0:15:21.240 have have shed any light on that. I mean, our 0:15:21.720 --> 0:15:25.680 physicists now thinking gravitons are more likely or less likely. 0:15:26.440 --> 0:15:28.560 So well, we certainly don't have any definitive proof on 0:15:28.600 --> 0:15:30.520 the matter yet. But I guess for the purposes of 0:15:30.560 --> 0:15:34.680 our discussion here, since we don't have proof of gravitons, 0:15:34.840 --> 0:15:37.600 we can't really come up with a scheme to employ 0:15:37.680 --> 0:15:40.400 them or manipulate them in some way that would give 0:15:40.480 --> 0:15:42.920 us artificial gravity. Yeah, so, I guess are the point 0:15:42.920 --> 0:15:45.000 of our bringing up gravitons is that you can't just 0:15:45.080 --> 0:15:48.400 wave a magic wand and say, ah ha, gravitons will 0:15:48.440 --> 0:15:51.440 be the thing we use to create artificial gravity in space. 0:15:52.040 --> 0:15:54.000 I mean, we don't know if they exist. If they 0:15:54.000 --> 0:15:56.840 do exist, I'm not sure anybody has a coherent idea 0:15:56.840 --> 0:16:01.320 of how they could be harnessed to provide artificial gravity 0:16:01.360 --> 0:16:03.960 in space. It just seems like I don't know what 0:16:04.120 --> 0:16:06.160 is So if they're generated by mass, would you not 0:16:06.240 --> 0:16:08.920 need mass to generate them? Yeah, I could. I looked 0:16:08.920 --> 0:16:11.160 around in my research and I couldn't find any, like, 0:16:11.760 --> 0:16:15.600 any real theories about how gravitons. If the exists might 0:16:15.600 --> 0:16:18.240 be utilized in this fashion, and I'm not I'm not 0:16:18.280 --> 0:16:21.280 aware of any science fiction that explores the possibility, but 0:16:21.320 --> 0:16:23.520 I would love to know about it. I think when 0:16:23.560 --> 0:16:25.960 it does, it's more just the kind of it's the 0:16:26.000 --> 0:16:29.320 hand waving magic. Right. So we come back to mass, 0:16:29.360 --> 0:16:32.520 then yeah, you could I guess, have a spaceship that's 0:16:32.520 --> 0:16:35.000 as massive as the Earth, and then that would have 0:16:35.560 --> 0:16:38.640 that would give you the gravitational pool you'd need. That's 0:16:38.680 --> 0:16:41.840 not exactly a terrible idea, and it's not unexplored. I 0:16:41.840 --> 0:16:44.480 mean there have been these ideas, for example, in you know, 0:16:44.520 --> 0:16:48.080 stellar engineering projects that say, hey, so let's say we 0:16:48.080 --> 0:16:51.080 want to travel to another solar system, wouldn't it be 0:16:51.200 --> 0:16:53.800 easier instead of trying to build an arc ship to 0:16:53.920 --> 0:16:56.480 take us there, to see if we can build a 0:16:56.560 --> 0:16:59.320 structure around the Sun that will reflect some of its 0:16:59.400 --> 0:17:02.040 radiation in and allow us to steer the movement of 0:17:02.080 --> 0:17:04.760 the entire Solar system. Oh yeah, yeah, I just move 0:17:04.840 --> 0:17:08.440 the Solar system. Yeah, so like the Solar system becomes 0:17:08.440 --> 0:17:11.920 our spaceship. You can build these things called a hypothetical 0:17:11.920 --> 0:17:15.399 structure called a scatterw thruster. Essentially, it would just drive 0:17:15.520 --> 0:17:19.159 the Sun Yeah. That actually features into No Surprise and 0:17:19.320 --> 0:17:21.600 Eda in Banks book, but I'm not going to say 0:17:21.600 --> 0:17:25.200 which one because it's kind of it's kind of a spoiler, Okay, 0:17:25.440 --> 0:17:27.960 but it's one of them. Leave it, leave it there. Yeah, 0:17:28.000 --> 0:17:30.560 So that is one idea though, if you wanted to 0:17:30.600 --> 0:17:33.320 travel through space on an object that has Earth gravity, 0:17:33.359 --> 0:17:35.840 you could just take Earth with you. Of course, it 0:17:35.880 --> 0:17:37.840 wouldn't really make sense to say, well, I want to 0:17:37.840 --> 0:17:41.960 build a spaceship that generates Earth gravity through natural mass 0:17:42.040 --> 0:17:45.800 generating effects, because then you would just be building a 0:17:45.840 --> 0:17:48.600 spaceship the massive Earth. Right. And if you can do that, 0:17:50.240 --> 0:17:54.600 then I mean you're already You're already a pretty powerful civilization. 0:17:54.640 --> 0:17:56.959 I'm not sure where you would rank on the Kardashian scale, 0:17:56.960 --> 0:18:01.440 but you'd be you'd be potent. Definitely a cardas chief one, 0:18:01.520 --> 0:18:04.720 maybe a cardas chief two. Alright, So we've talked about 0:18:04.760 --> 0:18:09.199 these scenarios involving natural gravity and and the idea of 0:18:09.240 --> 0:18:14.359 manipulating natural gravitational forces. Luckily we're not, we're not forced 0:18:14.440 --> 0:18:17.280 to contend only with those. We can also deal with 0:18:17.480 --> 0:18:20.720 artificial gravity, not in a magic sense, but in a 0:18:20.760 --> 0:18:24.160 but in a real sense. Yeah, and in this way, 0:18:24.720 --> 0:18:27.600 there are ways to generate artificial gravity that are not 0:18:28.240 --> 0:18:32.320 hypothetical or speculative at all. I mean, this is totally easy, 0:18:32.440 --> 0:18:35.960 standard settled physics, because one of the insights of modern 0:18:36.000 --> 0:18:40.400 physics is that gravity is in fact indistinguishable from acceleration. 0:18:41.040 --> 0:18:44.600 When you're being pulled toward a planet's center and the 0:18:44.640 --> 0:18:47.560 planet has a mass such that it generates a surface 0:18:47.560 --> 0:18:50.560 gravity of nine point eight meters per second per second, 0:18:50.600 --> 0:18:55.280 which is what Earth's surface gravity is, right, or whether 0:18:55.320 --> 0:18:59.120 you're accelerating through space at an acceleration rate of nine 0:18:59.119 --> 0:19:02.000 point eight meters per second per second, the effect you 0:19:02.080 --> 0:19:05.480 experience is exactly the same. You can't tell the difference 0:19:05.520 --> 0:19:09.840 between these two situations. And so knowing this, we couldn't 0:19:09.880 --> 0:19:13.760 turn the idea of acceleration to our advantage. And that's 0:19:13.760 --> 0:19:15.600 where our first model comes into play. But first we're 0:19:15.600 --> 0:19:23.479 gonna take a quick break. All right, we're back. So 0:19:23.520 --> 0:19:25.960 the first model of artificial gravity we're going to discuss 0:19:26.000 --> 0:19:28.080 here is the one that I alluded to earlier and 0:19:28.119 --> 0:19:31.840 discussing the expanse, and one that I think, by and large, 0:19:32.320 --> 0:19:36.280 I cannot think of another single science fiction property that 0:19:36.400 --> 0:19:40.640 employs this as their artificial gravity. On a spaceship. But yeah, 0:19:40.760 --> 0:19:44.959 linear acceleration, I can't really think of many that do. 0:19:45.119 --> 0:19:48.120 But so, what's the basic idea here, Robert? All Right, So, 0:19:48.520 --> 0:19:50.840 if you've ever written on a roller coaster and felt 0:19:50.840 --> 0:19:53.280 yourself plastered to the back of the seat, then you've 0:19:53.320 --> 0:19:55.560 experienced some of the power here. If you were in 0:19:55.560 --> 0:19:58.239 a fighter jet and you were, you know, traveling at 0:19:58.320 --> 0:20:01.920 a sufficient speed to pull you multiple g's, you're you're 0:20:01.920 --> 0:20:05.960 also experiencing this as you're pushed back into the chair. Right, So, 0:20:06.119 --> 0:20:08.919 if you can imagine being in that fighter jet and 0:20:08.960 --> 0:20:13.400 you're being pulled back into your chair, except instead of 0:20:13.480 --> 0:20:15.840 going back into your chair, you put your feet on 0:20:15.880 --> 0:20:18.879 the chair, put your head in the direction that the 0:20:18.880 --> 0:20:22.320 fighter jet is going, and the acceleration rate of that 0:20:22.440 --> 0:20:25.119 fighter jet is nine point eight meters per second per second, 0:20:25.560 --> 0:20:28.119 it would suddenly feel a lot like it feels to 0:20:28.200 --> 0:20:31.720 stand on the ground. Right. Imagine a skyscraper as a 0:20:31.840 --> 0:20:35.000 rocket ship. Imagine it blasting through space at such a 0:20:35.000 --> 0:20:38.280 speed that the G force uh equaled the pull of 0:20:38.320 --> 0:20:41.679 Earth's gravity on the internal environment. I'm actually gonna read 0:20:41.680 --> 0:20:44.480 a couple of quick quotes from James S. A. Corey's 0:20:44.600 --> 0:20:48.600 UH first Expanse novel, because I believe that these really 0:20:48.600 --> 0:20:51.720 capture what we're talking about. So he's describing the Donager 0:20:52.080 --> 0:20:56.439 space ship here quote. Like all long flight spacecraft, it 0:20:56.560 --> 0:21:00.240 was built in the office tower configuration. Each deck one 0:21:00.320 --> 0:21:03.440 floor of the building. Ladders are elevators running down the axis. 0:21:03.720 --> 0:21:07.280 Constant thrust took the place of gravity. Now, there's also 0:21:07.359 --> 0:21:11.320 a Mormon generation ship in the book that uses both 0:21:11.400 --> 0:21:15.000 linear thrust and a rotating wheel, which we'll get into, 0:21:15.359 --> 0:21:18.040 and this is the description for it. Each compartment within 0:21:18.119 --> 0:21:20.600 the massive rings was built on a swivel system that 0:21:20.680 --> 0:21:23.960 allowed the chambers to reorient to thrust gravity when the 0:21:24.040 --> 0:21:27.080 ring stopped spinning and the station flew to its next 0:21:27.240 --> 0:21:31.960 work location. Okay, so by describing these ships with floors 0:21:32.000 --> 0:21:34.560 like an office building, what you what you should really 0:21:34.560 --> 0:21:37.360 picture is like you've got a skyscraper and it's flying 0:21:37.480 --> 0:21:40.479 through space with the top of the skyscraper as the 0:21:40.520 --> 0:21:43.760 front the nose of the ship, and all of the 0:21:43.840 --> 0:21:46.480 floors are where your feet would be towards the back 0:21:46.560 --> 0:21:48.479 of the ship and your head would be facing the 0:21:48.520 --> 0:21:51.600