Didn't want to use the word travel, but yes. The chaos that might result from tampering with the past seems to controvert its possibility. But does it?
I'll say there appears to be less paradoxes with future time travel then past time travel and this link is very good as we have:
Carl Sagan on Time Travel
Listen to the late astronomer and Pulitzer Prize-winning author's insightful and delightfully droll views on everything from wormholes ("very Alice in Wonderland") to the nature of time ("one of those concepts that is profoundly resistant to a simple definition"). (text and RealAudio)
Traveling Through Time
In this excerpt from his 1998 book Time: A Traveler's Guide, Clifford Pickover, an IBM researcher and science writer, declares that "time travel is possible." Find out why he is so sure.
Think Like Einstein (Hot Science)
Albert Einstein showed that space is curved, time is relative, and time travel is theoretically possible. Here, do a simple thought experiment and learn to think like the century's greatest scientist.
What you would call a time machine physicists term a "closed timelike curve." Steep yourself on the concepts and conjectures, the dialects and definitions that physicists rely on when musing about the possibility of time travel.