Re: (TFT) Space travel - galaxy sized dyson spheres.

[PvK <pvk@oz.net>]

I'm sure there isn't enough Si to do that, nor even enough matter even if you could convert the rest of the matter outside the core into glass. "Regular" Dyson Spheres are around a single star (not around an entire galactic core), and even those are more the stuff of Space Opera more than sober science fiction, it seems to me.

The Wiki article too seems to be slightly off. In the first place, anyone who could actually build a Dyson Sphere would be able to figure out how to keep it in place, and second, even though their gravity argument passes basic physics, it doesn't consider the force of the solar wind, which would actually tend to center the sphere, since drift in one direction would (I think - I haven't done the math nor do I know how strong the wind would be nor of course how heavy the sphere would be) result in more wind force on the closer side, which might tend to naturally balance drift. As for the "falling in" problem, again I tend to think Dyson Sphere creators would have one solution or another (rope? Handi-Bundlers? magnets? wind? counter-gravity? force fields? glass floors and mirrors?). They make the point that it wouldn't just naturally have gravity going conveniently outwards, but it would hardly seem likely to be without some solution, if you can manage to build it in the first place. Particularly, it seems to me, since a Dyson Sphere seems highly unlikely to be an efficient idea for something to do if one had the means to do such a thing (i.e., there would be much more productive things to do with all that energy, technology and material), so the beings that could do that, would probably have even MORE technology than that needed to do it, unless they were all deranged with one-track minds focused only on doing just that.

PvK

--- Jay wrote:

"I'm not sure there's enough Si in a galaxy to shell itself, much less
leave anything inside, super massive black holes or no."
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