Why we can't "go back". I explained the paradox of backward time travel, in the old PFs, and I would like to do so again. Here is why it is impossible to travel backwards in time (and it doesn't matter how far backwards): As soon as you travel to a time that is before the exact time when you started traveling, you create paradox. If I start traveling at 5:00 A.M. (I know that using minutes, as a way of measuring exact time, is crude, but it should get the point across), and I travel back to 4:59, I have yet to start traveling. But, if I have yet to start traveling, how did I get to 4:59? The answer: I didn't, it's impossible. Unless someone can prove me wrong, it makes no sense to imply that I can start traveling, after having already arrived at my destination.