Viewing a single comment thread. View all comments

CubanHermes OP t1_j68rewy wrote

Reply to comment by mfb- in Is there an upper limit to structure size in a vacuum? Could a sufficiently advanced civilisation build a galaxy sized structure in space or would it become too massive and collapse in on itself? by CubanHermes

Would it have to be a ring though? I was thinking something like a galaxy sized 'metropolis' or like a solar system sized ship. Is that theoritically possible?

3

mfb- t1_j68xvb0 wrote

Multiple nested rings would work, too. Three-dimensional structures are more challenging. You could support them with rotating rings.

8

CubanHermes OP t1_j68ycdi wrote

Thank you for humouring me. So a giant cube of hellish proportions with many billions of interlocking rooms is out of the question.

3

mfb- t1_j68ytbt wrote

Billions of rooms are easy. If you make every room a 10 meter cube then the whole structure is just ~20 kilometers in diameter and gravity is still tiny. Each room would have as much space as the ISS, so the structure could potentially house the current world population (ignoring some practical concerns like heat management).

10

CubanHermes OP t1_j693pjj wrote

Ok, so I just need FTL travel, many galaxies worth of materials, some way to heat the place and billions of workers and we can make a hellish galaxy sized Ikea flat pack colony. Excellent.

7

GrumpyButtrcup t1_j69b000 wrote

Wouldn't your giant cube need cooling instead of heat? The heat is generated by the people and machines, so the tricky part is disappating the heat effectively. From what I understand it's harder to cool off in space than to heat up.

Since you're in a vacuum you lose all of that passive cooling we take for granted on Earth.

6

bestest_name_ever t1_j69htz5 wrote

Yes, and a compact shape like a cube makes that harder. But the main point is that any conceivable size is still much smaller than galaxy-sized. The death star for example, if it has a level of crew per volume that's comparable to a current ship, would hold several tens of trillions in personnel. And it's tiny, like a quarter the diameter of Ceres. But it could be built without requiring magic materials. Moving it would be a different issue.

6

PlaidBastard t1_j6995li wrote

I don't know where you're going with this, but you have my hexwrench in this battle, friend

3

bestest_name_ever t1_j69hxzj wrote

No. Billions of workers don't get you anywhere. You'll need numbers of workers you'll have to look up the names for.

3

mfb- t1_j6botff wrote

You need cooling, not heating. The heat loss scales with the surface of the structure, but heat production scales with the volume (if we just scale everything up). The volume grows faster than the surface. Even the ISS needs radiators already.

2

FogeltheVogel t1_j69wrs8 wrote

If you want to go full sci-fi with this, look into the concept of the birch world

2

CubanHermes OP t1_j69z02c wrote

Now we're talking. Off down a little rabbit hole I go...

1