Aside from the issue of whether FTL travel is possible, my understanding is not that you would get negative time, but you would get imaginary time.

The equation is for changes in relativistic time is:

**t[r] = t[0]/sqrt(1- v^2/c^2)** As you can see, if v > c, then the divisor becomes an imaginary number (i.e. a number that is the square root of a negative number).

That having been said, this is pure conjecture, as no-one to my knowledge has actually demonstrated that relativity actually holds true at faster than light speeds.

**G***eorge*