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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??

marked as duplicate by Napoleon Wilson, wbogacz, MattD, Pᴀᴜʟsᴛᴇʀ2, his Dec 31 '14 at 20:29

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  • 2
    "There must have been atleast one reality in which cooper joined the expedition without getting a clue from his own ghost" - Not necessarily. - "assuming parallel universes" - Drop that assumption and it gets easier. There was never such an alternate reality as there can't ever be a timeline different from the one we observed. The timeline has always looked that way and has always contained a time loop, there is no dedicated alternate timeline that started this timeloop, it's just always been present. – Napoleon Wilson Dec 31 '14 at 11:08

It is called Bootstrap paradox. Ideas or items from future are passed to past which in turn become the same item/ideas in the future. It is like giving idea to yourself from future.

This not only creates a loop, but a situation where these items have no discernible origin

Fox Example: in terminator movie, Kyle Reese is sent from future to past by John Connor. In the past,Sarah falls in love with Kyle, conceives to John. Sarah raises John. John becomes the leader and sends Kyle to future to save Sarah. This is going in circles. Also, Sarah gets the idea of naming his son "John Connor" from Kyle. There is no point of origin of the idea or where the story has started. This is called bootstrap paradox.


As shown at the climax of the movie, Cooper is in the Tessarect room which is a 5 dimensional entity. He can control time & gravity. As he can control time, he can go back to the time where his past self exists. Don't see the paradox.

Since he can access his past from his present, he sends the coordinates through controlling gravity in binary to that moment in the past where the dust storm occurs & Murph forgets to close the window.

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