I would conclude that space-time continuum eventually could be bended enough to enable travel in past. However it could only be done on observational level, that is, you couldn't change things in past, you could only observe transpired events like experiencing 3D film. That would be an awesome journey, and many riddles from our history would become answered. I wonder could one use astral projection to do exactly that? After all, is there a limit to power of mind?
It would make much more sense if you could actually travel back in time. If it was possible the past-and so history records and the present- would be crowded with time travellers; if for nothing else they came to out time in an attempt to stop us from doing something stupid. Plus, we all know time can be warped by gravity, having it move faster by comparison in one location than in another, hence you can go to a place of 'fast moving time' for a certain amount of time and then return to where you were in the 'future' while having aged less than you would if you have stayed there.
Plus, if time machines existed in any period of time, someone would have killed Hitler and there wouldn't be any world war two in history, its like terrorists and guns: they exist and they got 'em.
Actually, you are kind of right and kind of not. Exactly like everyone has been saying, time/space is like a series of frames in an eternal web, all possibilities exist as well as all moments in time. Living in the 3rd dimension means we travel through the frames progressively but never seeing all of it (look up 2D man in a 3D world video on Youtube to understand that concept).
The other thing funnily enough, is it's like Back to the Future in some ways (when Doc explains the alternate 1985 to Marty). If you go back into time, you will go to a moment that looks just like the one you knew but because you now exist in it, it's actually a parallel world. You can never enter a previous moment that happened because there were never two of you, you enter a parallel world that's ALMOST EXACTLY the same except this one has 'Past' you and 'Future' you in it.
SO.. someone did go back into time and kill Hitler but unfortunately it was in a parallel universe where that happened so our past in this one is never changed. This is how physics gets around the 'paradox' problem. There is no paradox if it's an alternative universe where that was always going to occur anyway. Remember every possibility (even seemingly paradoxical ones) exists in an infinite sea of universes. The observer creates reality for themselves.
I recommend The Wormhole series for anyone who wants to bend their mind in the realm of Quantum Physics
Edited by VvROMULUSvV, 02 February 2013 - 12:14 PM.