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I am creating a fictional society where the sovereign owner has complete control over all fully automated means of production, and treats the remaining population of this society essentially as pets (this is not the only society present in this setting, but it is one of the worst to live in).

For personal reasons, they have created a false hierarchy, a simulated rat races for their pets to struggle and compete within. The massive space habitat they've built for their population reflects this.

I've played around with several plausible space habitats that can check off all the boxes, and so far I've seen the most potential in the topopolis.

The main criteria is to create a habitat that:

  1. Inhabits the fringe of the local star system (Kuiper Belt / Oort Cloud area), to create a distance between it and the Owner's own residence among the star-lifting infrastructure around the Sun. ex. A topopolis built around a frigid dwarf planet.
  2. Must have a closed interior (why I picked a topopolis over a ringworld). To the inhabitants within this interior, the structure must seem like an endlessly ascending tower.
  3. Must create a loop where traversing the structure in one direction leads you back to where you started (why I chose a topopolis over a space elevator).
  4. Must have a false sense of verticality/up and down achieved through some method of simulated gravity. This is another reason I chose a topopolis over a space elevator; from the outside, there is no real up or down.

My issue deals with the fourth point: which method of simulating gravity should I use?

From my limited understanding of physics, I know of (a) using constant 1g acceleration to create a force pushing down on the inhabitants, (b) rotational spin gravity, or (c) something more esoteric/less hard sci-fi, such as microsingularities embedded within intersectional plates. True anti-gravity is a little too soft for my purposes.

With (a), I assume that rotating the topopolis along its circumference would not be the same as, say, accelerating a spaceship at 1g to create the sense of "down". With (b), I don't want the sense of "down" to be directed outwards to the walls, as in an O'Neil Cylinder. And with (c), I'd prefer something less esoteric.

Is there another method I could use that would make the interior of the topopolis feel like an endless ascending tower?

I've also considered scrapping the topopolis and just using a very long space ark accelerating at 1g with a wormhole at both ends to create a loop, but I don't want the space ark leaving the System.

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    $\begingroup$ Let me recommend you read Heaven's River by Dennis E. Taylor. His science is excellent, and the primary subject of the novel is a topopolis. It's really the topopolis equivalent of Ringworld. $\endgroup$ Commented Aug 4, 2025 at 16:17
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    $\begingroup$ It will be very difficult if not impossible to satisfy both infinitely looping and always up (without things like anti- anti-gravity). These rotating habitats simulate gravity with centrifugal force which positively increase with radius and angular velocity. While you can constantly and slowly increase the radius of the habitat to make gravity increase, when you loop back, the radius will be small. Similarly, if one section is rotating quickly, once you loop back, you must slow it down because you ended up the same place you started, where gravity is lower. $\endgroup$ Commented Aug 8, 2025 at 14:22

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The problem with accelerating anything is that the heavier it is, the more energy it takes (and it takes a lot of energy to accelerate something at 1g). Planets manage to do this because all that energy has been solidified into matter, but a space megastructure is a different story.

O'Neill Cylinders and topopolises manage this because with constant velocity, centripetal forces create the illusion of gravity, which for the purposes of g-sensitive life-forms, is typically sufficient. However, this gives you gravity toward the outer walls, which is not what you want.

So, if you were to accelerate a linear megastructure 'upwards' through a wormhole, you would be expending a lot of energy, and sooner or later (354 days) you'd reach lightspeed if you could maintain the acceleration relative to the planet. You'd also have the problem of relativistic time dilation with respect to the planet that you're trying to stay near.

If you wanted a 'tower'-like space habitat, you could always have a space-station with 'noob hammers'* like this one shown on Reddit's Elite Dangerous subreddit:

Coriolis station with noob hammers

These 'arms' could create sky-scraper-like towers where the inhabitants would be accelerated toward the outer ends of the structures, and could be stacked up. The only thing is that the gravity would be low near the hub and high at the outer ends. But if you don't mind that, this is the way to go.

Taking this idea even further, you could just have a Stanford Torus with a particularly thick ring with multiple floors. Again, the outer floors would have higher simulated gravity than the inner floors, but with such a design, the gee-difference between the inner floors and the outer floors could be reduced.

*(Why are these things called 'Noob Hammers'? Because Elite Dangerous is a game about flying space-ships, and new players have a tendency to try to fly between these rotating arms... and often get their ships swatted by them, if they get the timing wrong.)

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    $\begingroup$ In any object's own rest frame the mass is constant, because the velocity of the object in its own rest frame is of couse always zero. From its own point of view, the object can accelerate at 1 g from now to the end of time and never reach light speed; it is only external observers who notice that the mass increases and the acceleration decreases. $\endgroup$ Commented Aug 3, 2025 at 3:32
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    $\begingroup$ @AlexP Edited to reference the planet the OP wants to stay near. $\endgroup$ Commented Aug 3, 2025 at 4:17
  • $\begingroup$ I'm leaning a bit more towards the Stanford Torus, but the Noob Hammer intrigues me (might have to come up with a new name for it in-setting). To clarify, we would be accelerating the inhabitants along the arms to create the sense of "down" (could be towards the ends or towards the hub)? Would the arms still need to spin as they do in the game, and if so, would that create a contradictory push towards the walls? I'm also wondering if I could anchor some form of wormhole at each end, to create the loop I want. $\endgroup$ Commented Aug 3, 2025 at 19:19
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    $\begingroup$ @ElevenWaterMoon The whole thing would need to spin, and 'gravity' would be directed outwards. As for wormholes, they're theoretical... no-one has actually ever seen one. If you're using science-fiction standards, you can choose to have them. $\endgroup$ Commented Aug 4, 2025 at 3:13
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How about a large Stanford Torus? That gives you a loopback, if you travel along the inside of the rim at constant gravity. It also gives you a tower, in climbing from the rim to the centre, with gradually reducing gravity. However, that can be a climb of several hundred miles.

There's a fictional example you can mine for ideas in John Varley's novel Titan. Don't lift Varley's plot, which is rather old-fashioned these days, or his inhabitants, which are distinctive, but the physical details of the setting are well worked-out and convincing.

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