At 12:32 PM 23/04/99 +0200, Anders wrote:
> If you move mass
>through the wormhole, the mass will interact with the bracing field
>and this will change it. At least in the negative energy case you
>would get that the field got weaker as you passed mass through it, and
>if it ever got to zero, the wormhole will close.
Perhaps. But...
>it will not produce perpetual motion
This ever popular idea *isn't* a p.m.machine. It's simply a way of extracting energy from the gravitational field beneath one mouth and using it to drive a turbine. It's not essentially different, it seems to me, to the decades' old idea of mining a black hole's energy by lowering junk into it on a rope.
Damien Broderick