Inward Bound: How Should We Colonize the Earth?


Hello everyone, in this article we’ll discuss atlas towers (a specific version of which is known as a Karmen tower), “terrariums” (which is to say, the asteroidal space habitats from Kim Stanly Robinson’s 2312), space hotels, and futuristic cities that could be built here on the Earth, and in a slight tangent we’ll even talk a little bit about what alien civilizations would look like during a future time period in the universe called the black hole era.

Admittedly, this article is far from complete because we don’t cover nearly enough about the kind of arcologies that could be built on this planet or some other world; we do, however, discuss some interesting ones like the Ocean Spiral (an underwater oceanic city) and also a sea steading city that could be built on the surface of the sea. As you might have guessed from the title of this article, the discussion that we have in this article will represent the begining of a new series entitled the Inward Bound series in which we try to wrap our heads around the question: How should we colonize the Earth? And, of course, the answers that we arrive at could also be applied to other worlds especially when you realize that by using tricks like terraforming (or, probably even better, perraterraforming), many of the worlds in the cosmos will be wholly (i.e. terraformed) or partly (perraterraformed, for example) re-engineered to look a heck of a lot like the Earth. Now, answering that question that I just posed isn’t as simple as it might seem. The process of colonizing the Earth (or any world or any thing for that matter) is a natural process — that’s to say, it is something which occurs in nature and the universe. Now, that might sound like a pretty obvious point to make, but the reason why I make it is because a central axiom of science is that any physical phenomena in the universe can, in principle, be understood on some level using the scientific method. If you have been following along with previous articles (and, in particular, the ones from the Clarketech series), you’ll immediately recognize where this is leading: namely, to the notion of a new socioeconomic system and paradigm which we could call a resource-based economy (or RBE for short). The idea here is that socioeconomics—the design of not just whole cities and infrastructure but of whole societies and even “worlds” as well—ought to be determined using the scientific method. We do currently have extant systems (namely, the monetary and market systems) which are designed, to a certain extent, for the purposes of determining how humans ought to behave individually and in aggregate and, also, how our infrastructure and industrial throughput should be built and handled, respectively.

In future articles, we shall elaborate in greater detail on why these systems are highly insufficient and unsustainable and don’t really provide satisfactory answers to the central questions of socioeconomics but, to put things briefly, the fundamental reason why the extant socioeconomic systems do not work is because they are not based on empiricism and experimentation and, hence, are not based upon the scientific method. I fully realize that I might be losing some of my readers at this point who might find this a little difficult to follow along with, but keep in mind that I am giving a summary explanation on the problems of the extant socioeconomic systems and we shall save a more elaborate discussion for subsequent articles. Those subsequent articles will be a part of new series called, Post Scarcity Economics, in which we elaborate upon the notion of a resource-based economy. The Inward Bound Series will be inexorably related with the Post Scarcity Economics series because, ultimately, it is the scientific method which will allow us to determine the designs of infrastructure, cities, societies, and so on. In the Post Scarcity Economics series, we’ll have a scientifically rigorous and comprehensive discussion on how what we know from the science of human behavior can give us tremendous insight on how we ought to design human societies and civilization; we’ll cover what the infrastructure will be like in that series, but we’re going to be even more focused on social design. It is that series emphasis on social design which will designate the hazy line dividing the Post Scarcity Economics series and the Inward Bound series from each other. In this series, the Inward Bound series, the emphasis will be primarily on the industrial design.

Cities of the Future

As the Nobel Prize winning physicist Richard Feynman once enunciated, after more or less 400 years of cosmic exploration we are at the end of a vary effective method which has taught us a tremendous deal about the universe, and our place within it. Whether or not we are at the end of this method is uncertain and, indeed, there were countless times throughout history that physicists thought we had wrapped things up in terms of our understanding of the world only for a groundbreaking and revolutionary discovery to be made a short while later which showed that there was a lot that we didn’t know — famous examples of this include how shortly after Newton published his Principia, many of the worlds leading experts thought that “that was it”; but problems like the three-body problem and the predictions made by Maxwell’s equations eventually lead to some pretty remarkable breakthroughs which taught us that there was actually a ton of stuff that we didn’t know during Newton’s time. I personally do not think that we are at the end and, thus, we shouldn’t be hesitant to believe that today’s technology and knowledge of the world won’t one day be completely overturned within the next century. If such a transformation is made in our understanding in the next century, then the discussion which we have in this series will be totally outdated by the next century. And, the fact that our technology and scientific knowledge increases so rapidly is part of the challenge of predicting the future, and it is the fundamental reason why, as the industrial designer Dr. Jacque Fresco once stated, “There’s no such thing as designing the perfect utopian city. Everything is subject to change. There are no final frontiers.”

In other words, we’ll never have the “best” design for say a city since, in the future, new technologies and breakthroughs might be made which could enable us to make even better cities. But we can, however, build the best cities and infrastructure that is possible given present technology and scientific knowledge. Of course, in order to do that we must get a knack for applying the scientific method to industrial design and also of the technologies that are currently in existence. In this article, we’ll be primarily concerned with just having a brief discussion on some of the cities and infrastructure that we could implement; indeed, it is possible that not all of the cities and infrastructure and ideas that we discuss will make the “final cut” and be implemented into the infrastructure of a post-scarcity economy, but they are certainly worth discussing. The infrastructure that we’ll discuss, if implemented today, would cause substantial improvements in industrial efficiency and throughput.

Improving Industrial Efficiency

How, you might ask, would building something like a Karmen tower or orbital ring or building underwater, sea-steading, and sky-dwelling cities increase our industrial throughput? How would that increase industrial and economic efficiency?

Well, the answers to both of those questions have to do, mostly, with space-based solar power (SBSP) and orbital rings. Suppose that we had arrays of solar panels in space (these could be called space-based solar panels and the power they generate is called space-based solar power or SBSP for short) attached to an orbital ring erected around the world and attached to this globe with electrically conductive tethers (i.e. graphene); the SBSP generated by those solar panels could be converted into electricity and transmitted from the orbital ring to Earth-based infrastructure by sending that electricity across the length of the tethers. Now, that would be pretty awesome because space-based solar power is super energy efficient and dense (in fact, 8 times more energy dense and efficient than solar power collected from solar panels located on the Earth’s surface) and this power could power all of the Earth’s infrastructure for as long as the Sun is stable which could be, potentially, indefinite (ignoring big numbers and the quantum and cosmological effects which would take place over truly enormous intervals of time). Those tethers would be attached to the orbital ring and could terminate at an arcology located on the Earth surface or indeed even a sea steading or underwater city. We shall discuss below how such a system of electrification could extend from the orbital ring (or the peak of a Karmen tower) to anywhere on or within (think underwater or underground cities as examples) the planet Earth. And it is no surprise that building arrays of space-based solar panels circumferentially along the exterior of an orbital rings would dramatically increase our civilizations totally energy budget; indeed, the use of graphene cables which harness the Earth’s geothermal energy by transmitting heat from the mantle to an energy-conversion sight (which would, of course, be situated at the end of the graphene cable which is opposite to the end that is making physical contact with the mantle) would increase our energy budget even more. Furthermore, underwater cities combined with mostly automated exploration and mining operations on the sea floor would greatly increase our total materials budget. Furthermore, the orbital ring could be used as a remarkably effective tool for interplanetary trade and exploration and I’d even go as far as to posit that it is the best tool for interplanetary transportation that we have. Thus, I decided to add a discussion below of “terrariums” and mining asteroids for their resources which could be brought back to the Earth. Thus, it should be pretty clear at this point how such technologies would improve both industrial efficiency and throughput and it is highly plausible that we’d implement them (or, at least, some of them) in a post-scarcity economy.

The theoretical physicist Michio Kaku, expanding upon the works and insights of previous thinkers (i.e. Nickolai Kardashev and Carl Sagan), posited that one could determine just how advanced and sophisticated an alien civilization is based upon empirical and quantifiable metrics (which are far less arbitrary and abstract and much more so based upon the true efficiency and performance of machines and infrastructure in the physical universe than the metrics which we use today like GDP); these metrics for ranking how advanced your civilization is aren’t only things like that civilization’s total power output (which, of course, is the quantity taken into account by the Kardashev scale) but also things like the total amount of entropy produced by that civilization and the total quantity of computation performed by such a civilization. By measuring not just a civilization’s total power output but also the total amount of entropy that it produces as well, we measure not just how much energy that civilization is using but also how efficiently it is using that energy and how much overall waste and disorder such a civilization is producing as a result of its industrial practices. In a resource-based economy, we assume, axiomatically, that one of the principle goals of such a system is to maximize the efficiency of all industrial processes so long that this does not negatively effect humans and the biosphere. When one thinks as to how to create infrastructure with an optimal industrial system, we must realize that in order for the industrial processes occurring within our infrastructure to be truly “optimal” we must account for not only things like total power output and resource-throughput but also the amount of “waste” and “disorder” which are produced in the process and metrics like entropy (among others I imagine) empirically and quantifiably measure that waste and disorder. This means that in a resource-based economy the aim isn’t just to increase the total power-output and resource-throughput of your civilization (which is essentially the sole goal of capitalism and today’s economic paradigm) but also to minimize the total output of waste and disorder in the process and to do so as efficiently as possible.

We have examples of this. For instance, in a RBE it would make more sense to collect SBSP on an orbital ring and transmit that energy across tethers connecting the orbital ring to terrestrial arcologies on the Earth’s or some other world’s surface than the alternative which would be to microwave SBSP back to the Earth or some other world that you have colonized. The reason is pretty straightforward. In both scenarios, for a given square area of space-based solar panels, you are producing the same amount of power; but in the case of the latter, you’re wasting a heck of a lot more energy, especially during the energy conversions.

Vacuum Energy

Illustration of the Casimir effect    Image Credit:

Illustration of the Casimir effect

Image Credit:

That is one example of an RBE in a K1 civilization; there are, of course other examples in more advanced civilizations. In the SFIA episode, _______, we discussed what life might be like for a civilization a very, very long time from now — an epoch which cosmologists call the black hole era. This is a period of time which will begin roughly \(10^{40}\) years from now (long after the \(10^{10}\) years when the last star in the universe ceases to shine) and will last until roughly \(10^{100}\) - \(10^{106}\) years from now when the last black hole in the universe evaporates and disappears due to Hawking radiation. During this time, the universe will be dark and cold since all of the stars in the cosmos will have long been dead; the universe will be dominated chiefly by black holes. Thus, for any alien civilization which survives until the black hole era, the primary source of power will either be black holes or by tapping into the vacuum of space itself (the latter being called vacuum energy). Now there is some evidence that it would actually be possible to utilize vacuum energy. Empty space isn’t as empty as it seems; in fact, due to quantum mechanics, virtual particle—anti-particle pairs continuously popping in and out of existence. It has been shown that such virtual particle pairs exert a small amount of pressure; by placing two plates parallel to one another inside of a vacuum, those two plates will actually begin to approach one another due to an asymmetry in pressure acting on each side of the plates by these virtual particle pairs. As the virtual particles do work on the plates, energy gets extracted out of those virtual particles and converted into mechanical energy (the kinetic energy of the plates) and that mechanical energy could, in principle by used to generate electricity. We also see some evidence of vacuum energy being a potential source of space ship propulsion. In Nasa’s Eagle Work Laboratories, they demonstrated that a tiny amount of thrust could be generated form nothing — that’s to say, from empty space. Now people have been pretty skeptical of these results and you’ll oftentimes see people saying that this violates Newton’s third law — according to every action, there must be an equal-and-opposite reaction. This law forbids getting something for nothing; according to this law, you cannot exert a thrust on something without pushing back on something else. If space really was “nothing” then these critiques would be totally justified; but the simple fact is that space isn’t “nothing” and is, instead, more akin to a thin and sparse haze of particles that continuously pop in and out of existence. The fact that empty space can never actually be truly empty (due to the laws of quantum mechanics) means that a spaceship could get a small amount of thrust from vacuum power without violating Newton’s third law.

Black Hole Farming

Now, I imagine that any alien civilization living during the black hole era would certainly utilize vacuum energy. Another power source they’d make use of is the energy that they could extract from black holes; and keep in mind that black holes would be dominate in this era. This is something that we talked about in the SFIA episode, _______. For any civilization still around during this time, power and resources would be extremely scarce. They would want to colonize and build power-extraction infrastructure around as many black holes as they could for a reason analogous to why you’d want a K3 civilization to build as many Dyson spheres as they possibly again: because if you don’t, then a heck of a lot of energy is getting wasted. For a K3 civilization, any star that isn’t accompanied with some kind of Dyson swarm or Dyson sphere is radiating away all of its light energy out into space and, consequently, gets “wasted” without ever being put to any good use (like, for example, powering someone’s toaster). The same argument applies to civilizations still around during the black hole era. Black holes will continue to leak out energy in the form of Hawking radiation for roughly \(10^{100}-10^{106}\) years; any alien civilization which lives during this time would clearly want to make use of that energy. They could do so by building shell worlds around those black holes which could be used to extract their Hawking radiation. When you’re thinking about how a civilization could optimize its efficiency by minimizing the total amount of entropy produced and heat lost due to computation, it would be wise for them to wait until the black hole era to utilize the majority of their computations; computers would be most efficient during this time since the universe will be much cooler and, according to Landauer's principle, computers become increasingly more efficient at lower and lower temperatures.


Atlas Towers—Towers that Extend to Space

3D animation of a Karmen Tower (also known as an Atlas Pillar). This video was created by Jarred Eagley who is also a member of the SFIA production team.

Since we already have an entire article dedicated to orbital rings (which has become the second most popular article on the website), we’ll skip that discussion and talk about atlas towers which, in some respects, are similar to orbital rings, though they aren’t nearly as versatile and useful. Again, I’d like to reiterate a point I made earlier that in this article, we’re going to discuss some of the technologies and possibilities of future infrastructure while keeping in the back of our minds that not all of them would necessarily be implemented in a resource-based economy (though some of them, like the orbital ring for example, are pretty much guaranteed to happen sometime in the future in either a monetary-market economy or a resource-based economy).

For those of you who are unfamiliar with this concept, a Karmen tower (a specific version of an atlas tower) is an ultra-tall tower whose top exceeds 100 kilometers above the Earth's surface. The 100 kilometer mark is known as the Earth's Karmen line and represents the boundary between space and Earth's atmosphere. Solar panels would be attached near the peak of these towers; electricity produced by these solar panels could get sent down the tower through conductive cables and subsequently used to power a city. A Karmen tower could be used if we wanted to provide power to only one city. The source of power could come from space-based solar panels attached to the top of the tower.

Analemma Tower, Space hotels, and terrariums

But here's an alternative scheme. The Karmen tower could be attached to an asteroid; a nuclear power reactor could process helium-3 and deuterium (which come from the asteroid itself) in order to produce nuclear energy which could be transmitted down the length of the Karmen tower to the city. If that asteroid was hollowed out and its materials put off to the side, then a rotating cylindrical habitat like the so-called terrariums envisioned in Kim Stanley Robinson's 2312 could be built inside of the asteroid. This "terrarium" would essentially be a smaller version of an O'Neil cylinder where cities, homes, lakes, forests, and roads are located on the inner surface of the cylinder; the rotation of the cylinder produces artificial gravity (centrifugal forces, to be more precise) which keeps everything on the "ground." Any humans living in a such a structure could peer upwards (through, say, a telescope) and see people on the opposite side of the cylinder "walking upside down." (That might sound strange but it actually isn't too terribly unusual when you consider the fact that if (somehow) you could "see through the Earth" and watch people on the opposite side of the Earth, you'd see them upside down too.) Ultimately, the asteroid, the Karmen tower, and the arcology could be connected into a single super structure.

That is possible and indeed the idea of attaching a mega-skyscraper to an asteroid has been seriously considered. But hauling an entire asteroid into Earth-orbit is something that we probably wouldn't want to do. We could, instead, attach the tower to a space hotel (such as a Stanford torus) and that tower could extend beyond the space hotel to an orbital ring, which would, eventually, become a system of multiple orbital rings. (The prospect of a multiple orbital ring system for communication, planetary transportation, interplanetary transportation, and combating global warming is something which we discuss in more detail in our article on orbital rings.) Deuterium, helium-3, and other useful material could be mined from an asteroid or other celestial body in situ and transported to a space-based nuclear reactor; that reactor could, like in the previous example, produce power which could be transmitted across the length of a graphene cable and used to power a city such as an arcology. 

Depiction of arcologies located on the surface of the sea. (Click image to enlarge.) Image credit:

The nuclear reactor would produce a lot of heat during this process. If the Karmen tower was located above the sea near a costal arcology (see image above), then that heat could be pumped down pipes and used to power water desalinization plants which could be used by the local inhabitants of the arcology city. Indeed, directly beneath the arcology on the sea, we could build some kind of underwater city such as the Ocean Spiral which is essentially a vast spiral-shaped structure with orb-shaped structures situated in between the spiral that extends from the sea surface to the sea floor and this city could also be powered using aforementioned space-based nuclear reactors. Essentially, what I am describing is a system of cities, power generation sites, and other facilities which stretches from above the Earth's atmosphere in space to down deep in the ocean and eventually to the sea floor (and, indeed, to eventually below the sea floor as we shall soon discuss). Such a structure would be immense. 

The Karmen tower (which is essentially a giant skyscraper), the arcology on the sea's surface, and the Ocean Spiral (a spiral-shaped structure loosely attached to orb-shaped structures extending deep down below the ocean surface) could all incorporate cities, homes, recreational centers, and power production sites. Whereas the orbital rings system would consist of nuclear reactors and arrays of solar panels for production of energy, the length of the Karmen tower could perhaps incorporate wind turbines; the arcology on the sea's surface could also be powered by offshore wind farms and bobs which tap into the oceans tidal energy. Lastly, a boring machine could be used to bore a tunnel from the ocean bottom to the mantle; then, a graphene cable could extend from the mantle through the tunnel and up to the bottom of the Ocean Spiral. Graphene is one of the best thermal conductors known to science and would be able to transmit heat, for all practical purposes instantly, from the mantle to the underwater city structure. It is in fact the ambition of the entrepreneur billionaire, Manoj Bhargava, who created the documentary Billions in Change, to bore a tunnel to the Earth's mantle and, using a graphene cable, to tap into the Earth's geothermal energy and to use that energy to power the world. 

One of the big advantages of orbital rings is that we can build multiple of them around the Earth and at any orientation around the Earth; this means that the space elevators descending down from the orbital rings to the Earth's surface could in fact terminate at any point on the Earth's surface of our choosing. And this is true for any planet. Thus, you could have many Ocean Spirals, arcologies, and Karmen Towers which connect to the orbital ring. This is handy because an orbital ring system is probably the best planetary transportation system that we know of.


This infographic depicts the Ocean Spiral: a vast helical-shaped structure which would extend from the surface of the sea to the sea floor. (Click image to enlarge.)

Image Credit:

All systems including the space hotels and orbital rings in Earth-orbit, the Karmen/Atlas towers, the terrestrial arcologies and the arcologies on the sea surface, and the Ocean Spirals (and possibility other kinds of underwater cities) could all be connected into a single super structure. A boring machine, perhaps one like that used by Elon Musk's Boring Company, could be used to bore a tunnel to the Earth's mantle. A graphene cable would extend from the mantle to the Ocean Spiral which could provide geothermal power that could be converted into electricity. Elon Musk has proposed using his boring machines to bore underground tunnels on Mars\(^{[5]}\) which could connect underground cities; his proposed method of transportation between cities is rockets. It is worth mentioning that such a scheme would also be feasible on the Earth. Using this machinery, a network of tunnels could be bored underneath the sea floor; using either rockets like those proposed by Elon Musk or maglev trains (maglev would be preferable; see article), passengers could be transported from one Ocean Spiral to another, or indeed to underground cities that are below the sea floor.

Everything that we have discussed up to this point is in fact technically possible for the simple reason that it obeys the known laws of physics and nature; the caveat though is that such a project would be a formidable engineering project of epic proportions. However, given the extraordinary progress in scientific and technological understanding in the last century, to our descendants a few centuries from now such a task might not seem so daunting. Indeed, millennia from now, unless they destroyed themselves they would have, inevitably, visited other exoplanets in other star systems. Such infrastructure, extending from above the planets atmosphere down through its sea and even underneath its sea floor, might in fact be incorporated by our descendants on other nearby Earth-like exoplanets and perhaps even non-Earth-like planets, though this is purely me just speculating.

Illustrations of a floating city concept.  Images Credit:

Illustrations of a floating city concept. Images Credit:

Thus far we have discussed the prospect of using space-based solar power and nuclear power to provide electrical energy to terrestrial, coastal, and underwater cities called arcologies (or, to a larger kind of city known as an ecuomonopolis). We have discussed the use of such power sources to power a planetary transportation system, even more efficient than the one proposed by Elon Musk, which would incorporate a system of orbital rings, space elevators, and maglev trains. After millions of years the planets Venus and Mars could be fully terraformed and also incorporate cities and these same planetary transportation systems. Indeed such a system is scalable to many worlds including planets like Proxima B in the Alpha Centuari system or other Earth-like planets (natural or artificial) in other star system. Such space-based solar panels could be used to power an ultra-powerful array of lasers which could be beamed on numerous solar sail spacecraft, like those proposed by Project Starshot. We have discussed how this system could be used to create an "interstellar highway" between the stars; but it could also be used to create an "interplanetary highway" between planets. These spacecraft could travel at relativistic speeds between Venus, Earth, and Mars in a matter of hours. Thus people living on, say, Venus could receive materials from Mars in under one Earth day. Therefore, space-based power might not only be the key to creating an "interstellar highway" for voyages from one star system to another. but it might also be the key for making interplanetary trade and travel feasible, cheap, and convenient.

This article is licensed under a CC BY-NC-SA 4.0 license.


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