Shell Worlds: "Man Caves: Humanity’s Next Home" by Ken Roy

[lamontagne]

The two shell world papers were published in the Journal of the British Interplanetary Society, that has a peer review process.
The second paper specifically addresses the question of shell world stability, since it is such an obvious question.
Unfortunately, I don't have the specific paper so I can't comment on the math beyond the first page.  If anyone has the paper we could check the math?

[ppnl]

according to Wikipedia:

And based on my research (noted above)

{laughs}

I did not read the article

No kidding.

I did read the article. It is a short fluff piece with few details published by a science fiction publisher. Did not really impress me. The science fiction equivalent of a cute cat video.

It is true that for a large enough planet there will be a pressure gradient that will help stabilize the shell's gravitational instability. But such a large thin structure is likely to be unstable for a vast number of other reasons. And for small bodies the gravitational instability is still there.

The economic and technological power to make such a structure would also make such a structure obsolete. Imagine Tarzan trying to build a continental transportation system composed of a network of very tall towers and swinging ropes. Once you have the economic and technological power to construct on this scale you have much better options.

If you are serious about a shell world the best way to proceed is to plate the surface with with a meters thick metal and then dig out underneath. But once you commit to digging you don't need the metal shell any time soon if ever. You can proceed at your own pace for generations and if you eventual create a shell world then great. If not then you have billions of people in underground settlements.

[Lampyridae]

Maybe this is what Elon Musk was referring to when he tweeted about building his own secret underground city "like in Neon Genesis Evangelion." 

https://twitter.com/elonmusk/status/1210777492027363328

Digging up, digging out, and back-filling a canyon in Mariner Valley is probably a quicker and easier approach than bootstrapping an atmosphere on the entire planet.

St. Lowell in the anime Armitage III was built pretty much the same way, prior to terraforming.