Physics FAQ: Is Faster Than Light Travel or Communication Possible?
http://math.ucr.edu/home/baez/physic...Light/FTL.html

It might be thought that special relativity provides a short negative
answer to this question. In actual fact there are many trivial ways
in which things can be going faster than light (FTL) in a sense, and
there may be other more genuine possibilities. On the other hand
there are also good reasons to believe that real FTL travel and
communication will always be unachievable. This article is not a full
answer to the question which will (no doubt) continue to be discussed
in the newsgroups for the foreseeable future, but it does cover some
of the more common points which are made repeatedly.

See: http://math.ucr.edu/home/baez/physic...Light/FTL.html