Kaith Rustaz said:
It is the paradox of time travel.
You can't go back in time and kill your father because then you wouldn't be alive to go back in time to kill him.
By the same token, you can't go back in time and kill Hitler as a boy, because then you wouldn't have wanted to go back in time to kill him since he was never a problem so therefore he wouldn't be killed by you causing you to want to kill him.
Y'all with me on this?
Actually, I heard a far better example of this paradox by a physicist than the killing of an ancestor.
He stated that if you take two ends of a worm hole, and pull one of them at or near the speed of light for a distance, one end will open moments earlier than the other end. Worm holes are a widely accepted theory. Moreover, moving at or near the speed of light is understood to cause temporal differences based on Einstein's theory of relativity. So this presents LESS problems than simply traveling backwards in time, and is more likely possible.
In effect, anything that goes in one end, will come out the other end before it went in.
He proposed this experiment. If we line up the worm holes near each other, what happens if we toss a marble through one end of the wormhole, what happens if the marble comes out the other end and strikes itself, thereby preventing itself from entering the wormhole? Moreover, what happens when an astronaut flies through our imaginary worm hole and comes out before he went in, but this time pre-trip astronaut sees post trip astronaut, something post-trip astronaut didn't see before entering, and decides not to enter the wormhole, thereby making it paradoxically impossible for him to be there?
I always felt this was a more straight forward version of the problem that side steps a lot of irrelavent conjecture and gets to the core of the problem. No killing, no long term historical questions, just one HUGE PARADOX.
For example, are we now stuck with TWO marbles? If we are stuck with two marbles, where did it come from? There would appear now to be more mass in the universe that existed before, one marbles worth.
If there is only one marble, where did the other marble go? If you are post-trip marble, do you simply disappear, die? Irregardless, there were two marbles present at the same place and time where only one previously existed.