On Sun, 15 Dec 1996 Eliezer Yudkowsky <sentience@pobox.com> Wrote:
>>John
>>neither Special, General, or any other theory I've heard of
>>says "The speed of light is whatever I make it".
>Eliezer
>Curved spacetime = tilted light cones.
But it can only be tilt so much, a particle will always remain within its
light cone, if not then it would not only move faster than light it would
move back in time, and that has never been observed and is thought by most to
be impossible.
Well OK, Tipler found a solution in General Relativity that shows that an
infinitely long, extremely dense cylinder made of Neutronium (the stuff of
Neutron Stars) and spinning at almost the speed of light would be able to tip
a light cone enough to act as a time machine, but there are two very important
problems.
1) Nobody knows if a cylinder of finite length would work also, the math is
too difficult to figure out.
2) The very rapid rotation would cause the cylinder to fly apart. This is
much more than just an Engineering difficulty, no known force in Physics
would be strong enough to hold the cylinder together, not even the strong
nuclear force. For this to work new Physics would need to be found, which
is just another way of saying that as far as we know now it's impossible.
John K Clark johnkc@well.com
-----BEGIN PGP SIGNATURE-----
Version: 2.6.i
iQCzAgUBMrTxU303wfSpid95AQEQ6QTwzyi3Cpz4HjConQAocD/cpEXa4wfkRIox
eUaJkOntzQu6KxeKvQh1Ch2d5qnFQZxDjOQP4xE7DjKfXWxhKKEL8+jr674TyBaN
bp9Y+NdVikYYXqoPyjByBQZa1xpgNDgyxape9SBTTBrysJRqWxFhLx+tTU5ZShPr
5SxPxS/ND13nUXP7IZwAmjMEuc+vRP6WF8RsGwuxOr5Hr2tVOBY=
=T2yf
-----END PGP SIGNATURE-----