i believe "time travle" is very possible... just not the same way one might think. its not like traveling across space, if i go from point A to point B i know that point A is still there, and there isn't much i can to at point B that will effect point A. time does not work the same way. becuase of the many paradoxes that have been presented.
instead i believe that it must work, more like a tape measure. Time being the tape being pulled out. now would be where the tape gets its first glimps of light, where it is no longer ravled up inside the box. but every particle in space has its own tape measure, and the rate it gets pulled out is reletive to the velocity it travels. faster you travel the slower the tape gets pulled. now if you want to go back in time you can't travel too it you must instead rewind it. what you really want to do is wind back up all the tape in the universe, but leave yours the way it is. esentialy erasing everything that has happend beyond that point in time. every particles tape is independant of every others tape. therefor you and your existance can't be altered by anything you change. kill your parents,, you won't stop existing.
you cannot travel to the future however, becuase there is no future to travel to. all you can to is slow down how fast your tape is being pulled out, so that relative to you the rest of time will be being fastforwarded.
the reason you go forward (or backwards) is becuase you can't simply move your tape measure backwards to a certain point becuase the tape measure is immobile. your now cannot be moved to to yesterday or tommarow, it must remain now.. and everything elses now must also remain now. they are all lined up in the same NOW...
this makes sense according to the theory that if you go in a rocket ship close to the speed of light, and then return, you'll stay pretty much the same, while everything else will have aged. this isn't becuase you've moved forward in time. you've simply slowed down your rate of time. so that everything elses has essentialy fastforwarded.
time travel is indeed impossible. but changing the rate at which time passes, slowing it down, relatively speeding it up, theoreticaly even rewinding it is defidently plausable.
how this rewinding can occure may be impossible... but if it can be done, that is what will be happening...