You can travel in time on different planes than the physical one so when you travel through time it's like your a ghost. Since you don't have a physical body you can't move things or kill someone so you can't alter the past, just see it.
Re: Time traveling
By: Bloodmage01 / Novice Feb 02, 2011
Post # 6
Remember, time travel is dangerous. So even if you transport your spirit back in time, you might get stuck there. But don't worry about changing the past. Whatever you do will already be part of the past. But it is possible to physically travel back in time, just really hard and it's scientific, it involves no magic. There is a book called How to Build a Time Machine which tells all about the viability of time travel.