Originally posted by korothism
Suppose you travelled back in time and killed your biological grandfather before he met your grandmother. Then you would never have been conceived, so you could not have travelled back in time after all. Now did you travel back or not? The grandfather paradox has been used to argue that backwards time travel must be impossible.

Stephen Hawking once suggested that the absence of tourists from the future constitutes a strong argument against the existence of time travel.

But I personally believe (wish) that time travel is possible.

Here is the \\\"How time travel works\\\" article.... This is the best one available on the subject.


If you travel back in time you do not akter this reality, you alter someone elses, hence parallel universes.