One of the more famous time-travel related theories is called “The Grandfather Paradox”. What it basically means is: if you go back in time to a period when your grandfather is still very young, and you kill him, then you are supposed to vanish — because if your grandfather is dead, it means one of your parents was never conceived , which means you were never conceived.
On the other hand, let’s say you do go back in time, and you do kill your grandfather at a young age and you don’t disappear.
Then Gramma has a few questions to answer.
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