By popular demand, planetary scientist Grant Donoghue is back, and we continue our thoughts on the whole big wide spacey stuff. In this episode, we talk about living in space, and the limits of technology, and whether or not there are aliens out there.
00:00:00.320Hello and welcome to Brokernomics. Now by popular demand, planetary scientist Grant Donoghue is back and we're going to continue our thoughts on the whole big wide spacey stuff. So Grant, thank you for coming back.
00:00:13.780Very pleased that I'm apparently in, let's see more expression, by unpopular demand I have returned.
00:00:20.400Yes, well if our audience like it then very good. You know, we've got to look after the audience, haven't we? Because I mean they pay the bills and everything. They pay my bills anyway.
00:00:30.000Well in fact they don't pay my bills, they mainly pay Carl's bills. But I'm sure you and I are getting something out of it somewhere, yes.
00:00:38.160There is that. I've managed to do this one in the studio as well, which is nice.
00:01:04.300Yes. And then in the second one, we thought, well, what are the aliens out there? And we had a long chat and I think the conclusion was no bloody idea.
00:01:10.900Could be zero, could be many. I think if I had to bet on any number, I'd probably bet on zero.
00:01:16.620Maybe a few microbes in the odd alien plants or something, but who the hell knows.
00:01:23.600And in this one, we thought we might talk about living in space and a few other topics around that as well.
00:01:32.180But I seem to remember we were going to start with sort of the limits of technology, because you made a sort of interesting point when we were communicating about doing this one,
00:01:41.980that a lot of the technology just basically hasn't got a shuffle on.
00:01:48.140You know, jet engines of the 1950s are not fundamentally that different than jet engines of today.
00:01:54.860Well, there's a popular conception of engineering as downstream from physics.
00:02:01.000And in many cases, that's true. You know, it's you discover physical principles and then engineering is the way to exploit them.
00:02:07.000But the problem is that engineering predates physics by a long way and that in practice, that's really not how it works.
00:02:13.020You don't have physicists who are hired on who are explaining the universe to engineers.
00:02:18.080What's more, you have rules of thumb, you know, series of rules of thumb.
00:02:21.260So, and then you, and you, your physicists will let you develop and refine them and make them more precise.
00:02:26.740But all of that is, I'm so sorry. I think I just struck the microphone.
00:02:30.740All of that is, it is all dependent upon the ability for the universe to offer us things.
00:02:40.620I don't like to say exploit. I feel like I'm always defaulting to video game logic, but physical principles, which we can, which we can chase down and we can, we can turn to use.
00:02:49.980So, you know, for example, the fact that water is incredibly common, but it also expands many, many times when you heat it.
00:02:56.380And so that allowed us to develop the steam engine.
00:03:01.280But you gave the example of jet engines.
00:03:05.960The way that technological progress usually works in this respect with regards to engineering is that you have revolutionary and evolutionary phases.
00:03:12.880And you can use the example of firearms, right?
00:03:17.020Where you have muskets that got, they became, they were introduced as handguns, you know, in Europe in the, in the 15th century, handguns or however you want to pronounce it.
00:03:27.700But if you look at a musket from the 16th century, like a milket, you know, a Swiss milket or a brown bess from the 18th century, they're not actually that fundamentally different.
00:03:38.500And the brown bess isn't that much fundamentally better.
00:03:41.700It's, it's, there's, you have this revolutionary development and then marginal, marginal, marginal.
00:03:45.620And jet engines are a really good example because they show how a jet engine was revolutionary over a piston engine in that there was a period where there was parity and then the jet engines just took off.
00:03:58.120But then you ended up investing more and more and more for smaller and smaller returns because you're converging.
00:04:03.540And this is why, you know, early aircraft looked so different to each other, but modern aircraft all look so, so similar because you're converging on one, you know, on not, not an ideal,
00:04:12.080but on as ideal as possible, you can an exploitation of that physical principle.
00:04:16.620And the question is, is the universe going to keep giving us those forever?
00:04:20.060So, so throw in a bit of economics here.
00:04:22.240There is, there is a principle called Wright's law, which covers this.
00:04:26.180And it basically says in any sort of industrial process, each cumulative doubling of production, you get a certain percentage increase in efficiency.
00:04:37.420So, I mean, I looked at this in cars because it was part of my analysis when I was making my investment into Tesla.
00:04:44.440Basically, if you want to get a 15% cost reduction in making cars or efficiency or, you know, 15% improvement, roughly, you need to, you need a cumulative doubling.
00:04:54.600Now, at this point, that means producing something like 6 billion cars in order to get the next 15%.
00:05:00.360And so the thinking with my investment in Tesla is, okay, is electric cars, are they going to be on the same Wright's curve as normal cars, or are they going to get their own?
00:05:11.280Because if it's their own, doubling the number of electric cars is actually quite easy in the early days because there wasn't very many of them.
00:05:21.620So, I can imagine that this applies, whether it's 15%, it just happens to be that in cars, this applies to most technologies, that each cumulative doubling gives a percentage increase.
00:05:31.620But at some point, and probably only a few years into it for a mass-produced thing, you're having to churn through a hell of a lot of these things to get the next small increment.
00:06:46.780You can use special alloys and special principles to squeeze out little bits of efficiency in almost any engineering principle.
00:06:57.220I think it was Carl Goldsdorf who said, you can't save a ton on a locomotive, but you can save a kilogram in a thousand places.
00:07:06.740You can squeeze the efficiency out of a design, but that means hiring engineers to look at every little bit and find out where can I shave a half a meter?
00:07:16.700The Starship, at least as I understand the design philosophy, and I'm not an expert on propulsion, but as I understand the design philosophy, it's an attempt to do the opposite.
00:07:27.240You're relaxing those design constraints such that you can get something which is more tolerant of mismanufacturing or the stresses of being dropped in and out of the atmosphere of heating and cooling.
00:07:46.060Because if our broader topic is living in space, what does that tell us?
00:07:50.980I suppose what it tells us is the thing that we touched on in the first of our discussions, which is getting stuff up out of Earth is ridiculously expensive.
00:08:05.560And yes, we can expect improvements, but ultimately, it's probably only going to go so far.
00:08:13.020So if you are going to start living in space, well, basically, you're going to have to start making everything there as well.
00:08:27.580Let's say that you had a stairwell that you could you could, you know, build the Tower of Babel and and carry things up a stairwell to space.
00:08:34.340That's still actually quite a lot of energy compared to the cost of just making the things in orbit.
00:08:41.580And so so long as we are limited to doing something as expensive as rocket science to move something as simple as cargo from the surface of a body to the low orbit of a body,
00:08:50.900there's always going to be massive economic incentive to find some alternative method.
00:08:59.820So if people are if people are going to live in space, they're going to need to.
00:09:03.820So what we what we're going to need to do is.
00:09:08.780You know, let's let's let's move on to, you know, some of the megastructures as to how people might do this in the future.
00:09:14.080We're going to be heavily reliant on scaling up our industrial output, possibly starting at quite a basic level because you simply don't have the choice to do anything else.
00:09:29.120So so if OK, let's OK, let's come on to that.
00:09:32.880But we should probably skim by something like what are restricting principles for space living.
00:10:08.760And therefore, a future might look much more like an incredibly heavily populated solar system with possibly many times the population of something like the Federation in Star Trek or Star Wars or something like that.
00:10:25.400But all clustered around a single system, but not what you typically see in star sci fi, which is a huge number of planets with moderate populations, at least in the short term.
00:10:57.400But when I say short term, I mean in the scales of time that makes sense to history rather than thinking in geological or astronomical terms, in the sense that, you know, human beings will generate a concept and then we will propagate that concept outwards and lots of other human beings will interact with that concept.
00:11:14.480It's like you drop a stone into a pond and that reflects off of the edges of the pond in the sense that, you know, you and I can take actions and have discussions and have conceptions on that time scale before everything is lost to the noise of our stones being dropped in the pond.
00:11:29.520That is the sort of time frame where you would say, yeah, we're probably still going to be clustered around a star system or the star systems that we could reach in 20 or 30 years.
00:11:37.320But if FDL is out, then colonizing even the local stars is, what, tens of thousands of years?
00:11:48.160It depends how willing you are to play at the bounds of what is safe and sane.
00:13:50.920So megastructures, when we come to megastructures, so actually define for the audience, what are we talking about when we say megastructures?
00:14:00.860Megastructure is a term, like many speculative terms that refer to things we haven't, to classes of things we haven't built yet.
00:14:06.740No one can really quite agree on it or agree how seriously we should take the concept or where the boundaries should be.
00:14:11.100But broadly, megastructures refer to engineering projects, which represent an attempt to achieve some relatively simple objective, build a habitation sphere, or reduce something on the scale of geoengineering, which uses material in space that's orbitally significant.
00:14:31.680Where you can start considering the body as having the political and economic significance of a body like Mars or Earth.
00:14:43.480It's super large space stations, which rotate with sufficient, can make force to generate gravity, permanent habitation, or something as simple as that blasted idea of putting a sunshade between the Earth and the sun at the Lagrange point to try and fight climate change.
00:14:59.480It's the attempt to use engineering on a really quite grand scale.
00:15:02.620It kind of reminds me of what the Soviet Union tried to do and ended up drawing up a small sea.
00:15:07.480It's this wonderful dance between human ingenuity, human ambition, and human arrogance.
00:15:21.400Of the megastructures, I've got to say my favourite is definitely the O'Neill cylinder, because I can just see in the next couple of centuries most people living in one.
00:15:29.560So I would like to spend some time on that.
00:15:31.500But maybe the editor can throw up on screen what I mean by that.
00:15:34.840It's basically a large cylinder in which you can fit a large city or two, or possibly loads of farming space or leisure.
00:15:47.080It gives you plenty of space for a couple of hundred thousand people if you want it, however you decide to spice it up.
00:15:52.940But before we can get to that, coming back to our original thing that we talked about, you've got to build up your industrial capacity to get there, because you are most certainly not going to be launching a million tons of building material from Earth.
00:16:22.100And the reason the moon is the best candidate is just because it lets us get good at practicing things in space at relatively low stakes and relatively low costs.
00:17:30.500And by the time you've got something sufficiently outputted from that, well, then you can skip planets and you can go straight to megastructures such as the O'Neill cylinders.
00:17:38.860And once you have those, why do you need planets?
00:17:41.120I mean, this is something I asked you in a previous episode.
00:17:44.040It's like, why bother with planets at all?
00:17:47.200Do you know if you've got an answer for that?
00:17:51.060The problem, I think, with social planners in general is that they believe that they can reduce societies and people into writs of requirements in the same way that alchemists and somewhat unpleasant atheists can reduce people to what's a human being?
00:18:09.660Well, it's a certain amount of carbon, a certain amount of oxygen, and you can give a recipe.
00:18:14.540And, you know, in some literal sense, that's true.
00:18:16.760But I don't think you can reduce human beings to a life support requirement.
00:18:21.880Not without removing that thing which makes life worth living.
00:18:27.440How is this satisfied by Mars but not a cylinder?
00:18:31.880Because fundamentally, one is something like the pyramids, right?
00:18:37.540If you're building an O'Neill cylinder, that requires that there is a single person with a dream or an entity or all that idea.
00:18:43.800And you're building essentially to a pre-planned thing because you can't just have everyone doing whatever the heck they like.
00:18:49.080It is a coordinated engineering system.
00:18:51.140It has to be a closed loop because you can't waste your water into space.
00:18:56.360You don't have a local source of material.
00:18:58.260I mean, now there are there's conceptions of a beehive where you would build an O'Neill cylinder into a non-rubble pile asteroid and then you would have some local production.
00:19:06.640But nevertheless, you have to have something pretty close to a closed loop.
00:19:09.860And the whole thing is dependent on keeping a pressurized atmosphere.
00:19:13.300Well, you can live there, but you don't necessarily need to work there.
00:19:15.460So you can set these things up circling the Moon, Mars and Venus.
00:19:19.200So let's say, OK, we're going to we're going to go down the planet.
00:19:22.340We're going to have a we're going to have a base on Mars.
00:19:24.220OK, every time I go outside, I'm going to die of radiation or explosive decompression.
00:19:29.840If I go to Venus, my cloud city, as we started off talking about, because I did that.
00:19:34.040I think you got in touch after I did an episode with Bone, which he was arguing for Virgin Mars and I was arguing for Chad Venus.
00:19:40.100Venus is lovely and you're going to have your beautiful floating cloud city and something close to Earth gravity.
00:19:47.960But if you fall off, you know, it's it's not fun.
00:19:50.720You go outside on a bad day and there's a cloud of sulfuric acid.
00:19:53.820Yes. And your face just gets washed off.
00:19:57.760But if I have an O'Neill cylinder, I can I can spin it to produce whatever gravity I like.
00:20:03.820So I can, you know, when I'm in my 20s, I could be living on a on a one point two Earth gravity one and I'll get nice and muscly.
00:20:11.840And then in my old age, I'll move to a point six one.
00:20:14.520You can you can set your day cycle to whatever you want.
00:20:17.920So I'll be I'll be going for something between 26 and 28 hours because that way I get a couple more hours in bed every day and I get more done.