"The possible geological structure of artificial worlds."
Exploring designs and working of artificial worlds Ringworlds, Springworlds, Discworlds and Holloworlds. How to create and mintain a viable natural living environment identical to a planet.
Science fiction and fantasy offers us many kind of alien world but the most inspiring, challenging and imaginative are the grandest of artificial ones. The most famous of these are Larry Niven's "Ringworld" and Terry Pratchett's "Discworld". Who wouldn't like to live on, adventure around and explore the sights, sounds and smells of vast world that inspire the imagination.
In recent years I've been pondering on the theme of artificial worlds and how they might work, especially how to create Earth-like environments that could survive for thousands of millions of fun-filled and action-packed years.
My interest in the subject is strongly influenced not by the idea of the fantastical science and technology needed to build such worlds, we'll take that as a given truth, but how they could be made to work in the simplest fashion, using natural physical forces.
The basis of our human world is the geological forces of the Earth's core and crust, the constant movement of the Earth's tectonic plates, driven by the deep underlying flows of heat and mass as the dense molten core of our world swirls on its own hidden patterns. Without those flows of power deep in the Earth we would have the movements of the Earth's plats, volcanoes, the regeneration of the atmosphere through volcanic emissions and the recycling of material as ancient crust is pushed, pulled, dragged, melted and forced up, down, sideways over four milliard years.
The same or something very similar ought to apply for artificial worlds.
I imagine three artificial world types, the two I've already mentioned, Ringworlds and Discworlds and another, Holloworlds.
All artificial worlds need some kind of base plate structure and here I've imagined some very advanced semi-intelligent, reactive, flexible, shock, heat and radiation absorbent material with a variety of other properties. I call this Bondonium. Bondonium doesn't exist, you already knew this but I thought I'd better reassure you, but may exist in the future when our descendants, or ourselves if we become immortal create it.
Bondonium acts as the physical structure and support for the artificial world, maintaining them against any kind of damage for their entire lives, milliards of years. It's thick, it's black on the back side (absorbs everything remember?) and self-repairing. No damage will be suffered to my artificial worlds for long.
With that problem aside I'll focus on the base geology, the fun gurgling hot, sparkly stuff of liquid molten rock nightmares and Hollywood spectacle.
For my versions of artificial worlds to exist they'll need masses of hot metal. The Earth's core is made up of several layers all kept hot by the decay of radioactive materials (don't tell Greenpeace but we are actually living on top of a mega-sized nuclear reactor - planet Earth). The heat or radioactive decay keeps the rock molten and in motion.
Part of the Earth's molten rock motion comes through plumes of rock slowly rising up from the depth like fountains in air. They move so slowly it take millions of years to reach and effect the surface.
For example there has been a huge plume of molten rock under East Africa for over forty-five million years. Slowly rising to the surface it has been responsible for the creation and movements of the Great African Rift Valley, tearing apart a strip down through Africa for the last five million years, altering the environment and influencing evolution of life throughout the region, including the birth of modern humankind. This plume will continue to burn its way to the surface for tens of millions of years.
In the artificial worlds we need a way to create and guide plumes, otherwise the whole of the molten layer will just get hot, stay hot and have no influence - it will be a uniform heat.
In the artificial worlds they too have a molten layer of liquid rock several thousand miles deep, just like Earth from the surface down to the core. This can be a uniform mix of rocky iron, silicon and other good stuff with a uniform mixture of uranium and other radioactive materials to keep the rock burning for a very long time; but if we want to encourage some circulation of rock, create volcanoes, move tectonic plates around, crashing into each other to build mountain ranges we need a non-uniform distribution.
We need plumes.
There are two ways to create plumes as part of the world's circulation system, firstly we can create massive focal concentrations of radioactive material, hot spots, as special burners, secondly, we can create deeper pits, channels, trenches and other concentrations of additional molten and radioactive material. Or we can do both.
The idea of a non-uniform layer of molten rock means that the base plate of Bondonium will vary in thickness or have ridges, pimples and dimples on the back side, reflecting the presence of deeper concentrations of molten material above.
This is where the plumes are concentrated. Slowly they push rock upwards and draw molten rock from the surrounding areas, causing further circulation across wide parts of the artificial world.
All of this exists just to move the surface scum floating on top of the molten rock - continents, islands and much more happily bobbing around the artificial world for hundreds of millions of years.
Some continents will survive permanently, some will come and go over millions, or tens of millions of years. Some will be sucked or driven under others, some crumpled high into mountain ranges and washed away by the oceans.
And there will be oceans, seas, water. Water lubricates the whole surface system and must be present in abundance to supply that other vital ingredient - life. And so we have a world, floating continents on top of a thick layer of natural world-like molten rock bubbling away for thousands of millions of years.
There is one other reason for all that rock - gravity. All mass attracts, just as the thousands of rock under our fee on Earth creates gravity so the mass of an artificial world has to create its own gravity to support life in the upright position. Wherever you stand on an artificial world the gravity should always be pointing "down". I will suggest that Bondonium plays a role in artificially distorting the effects of gravity (yes, real superscience, hurrah!) to flow up-down and not sideways.
If all the mass of material created gravity in all directions you'd find yourself being pulled sideways by the effects of gravity from rock thousands of miles to each side or above, depending on the shape of your artificial worlds. So we'll assume this can be corrected by the kind of science capable of building such world.
Three worlds. Anyone with enough reading of science fiction will know the first two but I'll detail them for the new reader.
First explored in-depth by Larry Niven, the Ringworld is a huge ring, so vast it orbits a small sun. That thousands of miles wide and potentially tens of thousands or millions of miles in circumference.
Normally a Ringworld creates gravity by the force of its spin around the sun, but as I'm assuming rock performs that trick a few adjustments will be needed.
A few years ago I suggested a variant of the Ringworld, the Springworld, is a smaller artificial world, circling a world, a gas giant or something comparable. A smaller, less ambitious construct this may allow more material for a thick layer of hot rock inside for the geological workings I propose an still provide a habitat and abundant opportunity for wonderful adventures.
Orbiting around a gas giant, or circling around its own axis with nothing at the centre such a world could be crafted at a hundred thousand miles wide and million miles in diameter. That should give you about three hundred thousand million square miles of playroom.
The world is round and flat, it's a disc. So says Terry Pratchett and that's another fun way to enjoy life on an artificial world. Might make a good way station for interstellar journeys. Stop off and visit Discworld X on your way to Planet Poo.
You can imagine it any size, but if you want something more Earth-like in scale perhaps a hundred thousand miles across?
Small in comparison to a Ringworld/Springworld, but a nice little habitat for plenty of humans as their retreat, stopping off point, marketplace and much more.
The Holloworld is my own thought.
Take Earth and inflate a bubble of gas inside, coating the inside of the resulting bubble with Bondonium and you have a hollow world. This is a way to create something that looks like a planet, acts like a planet, smells like a planet but isn't.
Imagine a world about eighty thousand miles in diameter. That's ten times the size of Earth, but with the same gravity, because the molten core layer in still only a few thousand miles thick plus a few hundred miles of Bondonium.
Inside this is a hollow space upto seventy thousands miles across, and this is where we can have some real fun with engineering. Three worlds in one structure.
The Holloworld spins, creating a day-night cycle on the outside. That's going to be fun outside as the spin on the surface, for a 24 hour day might make the air move faster, creating rough seas and air movements. Interesting times will be had by all. Alternatively the world may be orbited by its own sun, so the sun does all the work going round and round. Another interesting challenge. Perhaps the world could have its own Springworld wrapped around to create day-night cycles without spinning too quickly? So many options, so many different situations and imaginative world combinations.
Meanwhile inside the Holloworld the spin on the inside surface of the Bondonium shell will give you the ability to create some form of artificial gravity, just like a Ringworld spinning to create gravity. That means the inside surface could have its own inner world, the upside-down inside-out world. An entire civilization living on the inner surface, with another or an outside branch living on the outside, or people moving between the two.
People move through vast, broad connecting funnels, one at each pole and a few dotted around the world, of Bondonium that pierces the molten lava shell like shallow volcanoes holding back the molten lava, the crushing weight of continents piling up against them and trapping the inner atmosphere.
Thousands of miles high, or deep, equally broad with twisting corridors to help trap air and the rest of the inner environment while allowing people and materials to flow safely to and from the inner and outer worlds changing orientation with the differing gravities from inside to out and visa versa, itself a source of useful story ideas following the adventures of characters travelling from one to the other.
The third world in the Holloworld is within the vast void of the inside shell. That's a hollow sphere seventy thousand miles across, filled with air, enriched with minerals and moisture, a complete living, breathing freefall environment.
We've seen a few such floating worlds, floating rocks and islands in past stories, comicbooks and, most recently in the film Avatar. Here is the opportunity to create a complete "world" that has no ground but floats in a vast chamber of air constantly moving due to the motion of the outer shell.
As for light and heat. The shell is insulated and there is no reason why Bondonium cannot be modified, being a wonder material of the future, to emit a glow throughout the sphere and reflect all light within, bathing the entire chamber in perpetual light, powered by the heat of all the molten rock outside?
In the Holloworld at its north and south poles, in the centre of the Discworld and, say, at twelve evenly-spaced points around the Ringworld/Springworld you may have Bondonium mountains rising on long shallow slopes above the molten rock ocean and its thin crust of habitable rock and water.
The mounts provide totally permanent structures, for service, maintenance, for a habitat and realm of the "gods". All the normal geological activity on the natural crust will eventually wipe out any trace of cities, palaces, etc. But you need to have one or several or more permanent locations that never change, that are totally proof against erosion, against decay and the crushing forces of the molten oceans of rock and the planetary crusts.
If you are an immortal species you need an immortal home, an "Olympus" rising high above the plains, the mountains and the tides of geological force. Ample room for palaces, luxury villa, entire communities and all their resident support and maintenance.
Here is the control room, the workshop, the spacious habitat for those who use artificial worlds as their playgrounds or who maintain them on behalf of their natural inhabitants, visitors and the vast stocks of wildlife. Here are the major spacefields and landing harbours for the grand starships and other clutter of any space-faring civilization, or the cosmic transport engines to move an artificial world to a new location anywhere in the cosmos or the universe.
Here is unique machinery to sustain the integrity of the Bondonium and prevent decay or corruption of the material and its operation. Here are the strange vast machines and layers of near-living strata reaching out like a web throughout the Bondonium to regenerate the radioactive decay elements in the molten lava, refuelling the ongoing processed of heating and maintaining the thousands of millions of years of geology on the artificial world. The lava will still be fluid long, long after it would have been frozen on any natural world.
For occupants you can imagine anything from a single lonely immortal janitor looking over the well-being of an entire world, or a vast community preserving, protecting, and enjoying it as they dance their way to the end of time, before moving it and themselves off to another cosmic realm.
Artificial worlds are purely speculative fantasy fiction rather than hard core science fiction, not based on real science or engineering but if our science progresses as the rate we've achieved for the last few thousand years we may one day, with suitable immortality (a completely different progression of science) be looking at the opportunities to create and enjoy the adventures on such worlds.
The cosmos is a vast place with plenty of materials floating out there, if not already claimed by existing civilisations we can look forward to tapping into some of it for such projects, as a challenge, for fun, for experimentation.
In the meantime they are ripe for the entertaining creative process. I've already been working on a few ideas for a far future civilization that builds hundreds of discworlds and Ringworlds/Springworlds for their own amusement and adventure. I will add a few gross of Holloworlds to the mix for additional stories.
Let's imagine a hypothetical material a form of artificial intelligent non-organic but comparable cellular structure that's hundreds or more miles thick and grows of its own accord one its pattern has been set.
The material will form an extremely rigid, sturdy structure to become the base shell for an artificial world capable of withstanding and repairing itself and its world for thousands of millions of years.
Part of this come from the use of smaller cellular components, like an organic cell on a larger scale, that locks into all surrounding cells in three dimensions, four dimensions if you incorporate a time dimension for weirder functions and resilience.
On the underside of the shell it's reactive to radiation, absorbing all radiation as a fuel source and camouflage for the outside universe. Micro particles through to small asteroid impacts can be absorbed with ease. Larger collisions either don't occur or are slowed enough to be absorbed. The process of slowing any larger collision exploits local surface gravity focussing on the target object until it touches and is crushed by the reactive nature of the material. This does not apply so much on the inside surface of the Holloworld.
Through this absorption process all materials the artificial world comes upon will add to replenishing the shell to prolong its life and providing reserves for any other purpose.
There will be wear and tear, albeit on a geological scale of time. Part of this is due to the reactive nature of a shell when coming into contact with larger bodies, shifting masses of material to response to a threat/opportunity. An asteroid doesn't touch a shell on impact but collides with scores through to millions of shock absorbent needles/roots reaching out to connect with it on the underside.
For the upsides the Bondonium uses other spatial manipulation to distort space around the artificial world, steering any perceived danger around the back side to be devoured when appropriate.
Please do be careful when approaching in your starships or TARDIS.
Keys: Science fiction artificial worlds, Ringworlds, Springworlds, Discworlds, Holloworlds, the geology of creating and sustaining a nautral environment in an artificial world. World-building, planetary engineering.