Obtainable Ringworld around the Earth?

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

> In the proposed LEO scheme, the outer ring would still be static
> relatively to Earth - well, in fact it would rotate once in 24 hours
> accompanying Earth, but at just, say 200Km of altitude, its speed
> would be far lower than orbital. The inner ring, however, would rotate
> *much faster* than orbital speed (in order to fake 1g gravity pointing
> outward). Therefore it would press the outer ring outward,
> counteracting the inward pressure of the outer ring weight; thus the
> outer ring would not fall over Earth and the inner ring would not
> centrifuge-rip itself apart. Of course the masses of the rings would
> have to be precisely matched so that those effects would cancel
> themselves exactly and the structure would be static around Earth.
>
> I guess I need to draw a diagram of the forces involved to make the
> idea clearer... Perhaps at night.

Ah, I begin to see. But if the the forces are to be balanced, and one
ring is moving much faster than the other, then the faster-moving ring
needs to be LESS massive than the slower-moving ring. How much less
massive? How Fast?

There is no way in Heaven, Hell, Earth or Space that I could do the
math for this. But the idea does seem doable.