Re: Interesting concultural ideas

> Astrophysicists have shown that solar tidal forces are negligible
compared
> to lunar ones. As long as the ring was somehow kept at the exact same
> distance from the sun along its entire length, there would be no force
> differentials to cause shearing. In fact, I would think that the sun's
> gravity would make the ring *stronger*, for the same reason that a
> free-standing arch doesn't collapse inward under its own weight. Equal
> amounts of force from all directions will cancel out to a net force of
zero.

Actually, I did teh maths not too long ago. the tidal forces are:

Sol-Terra  = 0.506 um/s^2 (um = micrometres)
Luna-Terra = 1.101 um/s^2

So, Sol creates roughly half the force that Luna creates. Smaller, yes.
Negligible, no. This tidal force assumes teh ring has a thickness equal to
the Earth. The number can be multiplied by whatever the actual thickness
is divided by the Earth's diameter; it is a linear relationship.

If you want the Sun's gravity to reinforce the ring on the arch principle,
you don't want the ring to spin at all, as taht would counteract the
arch-esque reinforcement. An obvious corrolary of using the sun's gravity
to reinforce the ring on teh arch principle is that on teh inside, gravity
would be in the direction of the sun; people would naturally fall upwards.
If teh ring had enough mass to create a local gravity greater than that
exerted by teh sun (not difficult at this scale), the arch benefit would
again be lost.

--
Fabian
Teach a man what to think, and he'll think as long as you watch him. Teach
a man how to think, and he'll think for the rest of his life.

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