starship-design: FTL idea

["Kyle R. Mcallister" <stk@sunherald.infi.net>]

Greetings:

I know this is a bit off the list topic, however...

Things that cannot travel faster than light, such as normal matter,
called tardyons, are prevented from travelling at C, since at this high
velocity, the tau factor reaches infinity, and mass becomes infinite.
Therefore, no force can move it faster. Massless particles called luxons
(photons, gravitons, etc.) travel at light speed since they have no
mass. They can neither be slowed down, nor sped up. (light slowing down
has been observed, but is do to retransmission rates in a dense
environment). Tachyons, FTL particles, travel faster than light since
they have imaginary mass. What happens when you have negative mass? This
has only been observed between casimir cavities, and they certainly
don't exceed the speed of light, yet light speeds up in the cavity.
Maybe negative mass particles travel faster than light? Or speed up
light? 

Causality violation:
Stephen Hawking has speculated that at FTL speeds, particle-antiparticle
anhialations dampen out chronal distortions, thus preventing causality
violation. Perhaps FTL IS allowed in this way, preventing causality
violation. In effect, the "naughty" part of your trip is prevented from
creating CV's since it is hidden behind an event horizon.

This brings me back to my question: What happens if you surround a
normal object with a spherical shell casimir cavity? I don't know if I
would want to be the one to try it.

Kyle Mcallister

P.S: If two objects APPROACH, each one travelling .99C, what is their
combined velocity of approach? Is this done the same way as the regular
velocity addition?