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In Interstellar, Cooper is able to communicate with his daughter once he enters the Black hole and he is revealed to be the ghost sending messages. This seems to be a paradoxical situation as he stumbles upon the NASA station thru these very same messages. So the sequence is
- Cooper is given a message about the location of the NASA station
- Cooper goes to the location and joins the expedition
- Cooper joins the expedition and eventually gets into the Blackhole
- Cooper sends message across space time to guide himself to the NASA station.
How is this possible? There must have been atleast one reality (assuming parallel universes) in which cooper joined the expedition without getting a clue from his own ghost??