OK, so what you do is to build a hollow sphere the size of the
Earth. Make the shell of whatever works best (probably doesn't have
to be diamondoid), maybe 1 000 metres thick, with maybe another 1 000
metres or so of dirt, rocks, etc. on top of that. Stuff the whole
thing with Utility Fog (maybe just a layer 10 000 metres thick).
Fill the rest with air. Do not rotate. The UFog pushes people, etc.
against the inner shell (or rather, against the dirt and such).

Heck, you can probably put the UFog right against the shell, and let
it form the rocks, water, and so forth. Even "wildlife" could be
simulated to a high degree of realism. Want dinosaurs? You got
dinosaurs.

But even if the UFog was relatively "stupid," it aught to be able to
do the basic job of "hold everything down."

Xenophile (taking off on a flight of fancy, yes, but still, it seems
doable, given UFog)

Just stressing: supposing that UFog is possible, then you could make
that bigger or smaller than Earth. Size would not be an issue. In
theory, you could have even a "Little Prince's Planet" for just one
person.

Another "options" ("options" is in quote marks because I don't think
seriously that they will ever be *viable* options :-) would be:

- An outer spheric grid of ultra-powerful magnets (perhaps made of
meta-stable metallic hydrogen or other sort of
magnetic/superconducting "unobtenium") that would push everything
against the inner "crust" shell through diamagnetism. Of course
ferromagnetic objects and electronics would likely be a problem under
this scenario.

- An inner black whole or chunck of quark matter in the center of the
"crust" sphere, massive enough to produce *actual* gravity on its
surface.

On Wed, 20 Oct 2004 23:43:43 -0000, Xenophile wrote:
>
> OK, so what you do is to build a hollow sphere the size of the
> Earth. Make the shell of whatever works best (probably doesn't have
> to be diamondoid), maybe 1 000 metres thick, with maybe another 1 000
> metres or so of dirt, rocks, etc. on top of that. Stuff the whole
> thing with Utility Fog (maybe just a layer 10 000 metres thick).
> Fill the rest with air. Do not rotate. The UFog pushes people, etc.
> against the inner shell (or rather, against the dirt and such).
>
> Heck, you can probably put the UFog right against the shell, and let
> it form the rocks, water, and so forth. Even "wildlife" could be
> simulated to a high degree of realism. Want dinosaurs? You got
> dinosaurs.
>
> But even if the UFog was relatively "stupid," it aught to be able to
> do the basic job of "hold everything down."
>
> Xenophile (taking off on a flight of fancy, yes, but still, it seems
> doable, given UFog)
(...)

You're evil, Xenophile! Your post triggered a process of UFog Gravity
Madness in my head and I can't stop thinking about the damned thing!
:-)

Another implications that I thought of:

- Your "planet" could indeed have an arbitrary shape or orientation.
For instance, you could still have a hollow sphere, but have a
habitable world in the *inner* surface - a kind of artificial
Pellucidar. Of course (like in Pellucidar) your would need some kind
of artificial "sun" at the center of this structure to power a
photosynthesis-based biosphere. Pretzel-like planets, cubic planets,
everything would be possible, though of course some shapes are more
engineering-friendly than others.

- From a biological viewpoint, UFog would be far from perfect.
Although your bones and muscles would remain stimulated and healthy,
your bodily fluids would flow evenly along your body and you would get
a puffy face and congested nose, as normally happens in
weightlessness. Also, you would show some immune depression in the
same way.

On Thu, 21 Oct 2004 14:38:28 -0300, Lucio de Souza Coelho
wrote:
> Just stressing: supposing that UFog is possible, then you could make
> that bigger or smaller than Earth. Size would not be an issue. In
> theory, you could have even a "Little Prince's Planet" for just one
> person.
>
> Another "options" ("options" is in quote marks because I don't think
> seriously that they will ever be *viable* options :-) would be:
>
> - An outer spheric grid of ultra-powerful magnets (perhaps made of
> meta-stable metallic hydrogen or other sort of
> magnetic/superconducting "unobtenium") that would push everything
> against the inner "crust" shell through diamagnetism. Of course
> ferromagnetic objects and electronics would likely be a problem under
> this scenario.
>
> - An inner black whole or chunck of quark matter in the center of the
> "crust" sphere, massive enough to produce *actual* gravity on its
> surface.
(...)

--- In spacesettlers, Lucio de Souza Coelho wrote:

> You're evil, Xenophile! Your post triggered a process of UFog
> Gravity Madness in my head and I can't stop thinking about the
> damned thing!
> :-)

BWAHAHAHAHAHAHAAAAAAAAAAAAAA!!!!!!!!!!!!!!!!!!!

> Another implications that I thought of:
>
> - Your "planet" could indeed have an arbitrary shape or orientation.
> For instance, you could still have a hollow sphere, but have a
> habitable world in the *inner* surface - a kind of artificial
> Pellucidar. Of course (like in Pellucidar) your would need some kind
> of artificial "sun" at the center of this structure to power a
> photosynthesis-based biosphere.

Pellucidar is what I had in mind. Notice my mention of dinosaurs.

The interior of a massive sphere is weightless, so ordinary gravity
is out. Gravity can be simulated via rotation, but that wouldn't
work for ERB's Pellucidar, which is inside the 1/1440th of a RPM
Earth. Also, with very large spheres, there is a whole lot of low-
gravity space, so unless that is what you are going for, humonkious
rotating spheres are out. I understand that UFog isn't air-tight, so
in needs to be inside anyway.

> Pretzel-like planets, cubic planets, everything would be possible,
> though of course some shapes are more engineering-friendly than
> others.

My circle-planet is coming up next. V_V

> - From a biological viewpoint, UFog would be far from perfect.
> Although your bones and muscles would remain stimulated and healthy,
> your bodily fluids would flow evenly along your body and you would
> get a puffy face and congested nose, as normally happens in

Sounds like me right now. I might not notice the difference.

> weightlessness. Also, you would show some immune depression in the
> same way.

I suspect that at least some of this is the fact that astronaughts
and those in bed-rest studies are in nearly sterile environments.

Xenophile (who posted this same thing at some Edgar Rice Burroughs
groups, under the title "Building Pellucidar?")

On Thu, 21 Oct 2004 21:09:02 -0000, Xenophile wrote:
[snikt]
> Pellucidar is what I had in mind. Notice my mention of dinosaurs.
[snikt]

For some reason, I misinterpreted your text and thought about a hollow
sphere inside a transparent bubble (to retain the air), with natural
sunlight and real 24 hours rotation. Also a theoretically possible,
and very Earth-like, design.