What do you guys think of this video i found on youtube??? Time travel possible?

Question

http://www.youtube.com/watch?v=drnm...

???

Answer 1

no

Answer 2

no, time travel is impossible firstly because if we did it and altered the past this would open up the universe to the possibility of a paradox occurring (see the answer to the question asked in physics section as to whether or not we can alter past events) and secondly because even by observing events in the past we would be altering them (quantum laws) and so changing the present and again opening up the universe to the possibility of a paradox.

paradoxes cannot exist in the universe, because they defy logic.