Re: Hard Sci-fi?

On Sat, 19 Apr 2008 09:46:46 -0700, Ben Crowell
<crowell08@[EMAIL PROTECTED]
> wrote:

>When it comes to FTL, I think there's also a lot of fuzziness involved.
>FTL is not entirely forbidden by relativity. However, there are certain
>flavors of FTL that smell more clearly bogus to a physicist than others.
>The FTL in Sagan's "Contact" smells relatively non-bogus to me, whereas
>the FTL in Star Wars smells completely bogus. One of my bogosity
>criteria is that the structure of relativity dictates that any mechanism
>for FTL should also be a mechanism for time travel. Another is that,
>because of the way general relativity is put together, any mechanism for
>FTL should require control over godlike amounts of mass and energy.
>"Contact" passes both of these tests, and Star Wars passes neither.

Read the late Dr. Robert Forward's "Timemaster". for FTL that does
include time travel and *doesn't* require godlike amounts of mass or
energy.

It merely requires the existemce of matter with negative mass. Which
is not forbidden by theory. :-)

He even dealt with causality problems.