It’s taking me a few days but I believe I’ve sold the bootstrap Paradox in the movie Interstellar. If you don’t know what the bootstrap paradox is it’s a paradox which is pretty common to all science fiction movies dealing with time travel in that whereby items or information are passed from the future to the past, which in turn become the same items or information that are subsequently passed from the past to the future. An example of this is: A professor travels forward in time, and reads in a physics journal about a new equation that was recently derived. He travels back to his own time, and relates it to one of his students who writes it up, and the article is published in the same journal which the professor reads in the future. Sound familiar? As this basically what happens in Interstellar. How?
Cooper in the future tells himself in the past, information (NASA headquarter’s GPS coordinates) which he uses to bring himself to the future. How does he do this? The explanation in the film is that beings who either live in a 5th dimension or have mastered control of it have built a construct (called a “tesseract”) for Cooper to communicate with Murph in her room through multiple points in spacetime. The tesseract is basically a 3D model of the fifth dimension and it was built in this way so that Cooper (a 3D being) can understand it. Through conjecture, Cooper infers that these beings are Future Humans who are saving “themselves” from extinction. As if the present day humans go extinct, then obviously there will not be future humans. The paradox is then how can future humans save present day humans from extinction if future humans don’t get the chance to live since present day humans will die before future humans can save them?
So how does Interstellar solve this paradox? Through “Plan B”. If you recall Plan B is sending and growing the half a million human embryos somewhere habitable to continue the human race. We can imagine that since Plan A fails without Cooper, Plan B succeeds since it was Prof. Brands plan all along. We can infer that without Coooper, the Endurance goes through the wormhole to Edmund’s planet since the Anne Hathaway’s character Amelia Brand is in love with him and would choose his planet first and would probably have veto since Cooper isn’t there anyway. We can then imagine the humans thrive and develop over thousands or even millions of years and once they have mastered the 5th dimension, they say, “Hey let’s save our ancestors for fun” and then the events in the movie played out.
Admittedly, there are few minor issues with this:
1) Future humans could screw up the past in such away that they erase themselves from existence (similar to the Mad Scientist Paradox). Though I believe since they have mastered the 5th dimension and are able to create “computer models” of what could happen if they save humans, they’ll see just like in the movie Amelia Brand does still make it to Edmund’s planet with the embyros.
2) Amelia Brand infers that someone placed the wormhole near Saturn 50 years ago as wormholes don’t just pop out of nowhere. It’s impossible for her to know this for sure and even real physicist believe wormholes randomly pop up all the time even on Earth, though they are so tiny and close up so fast we can’t detect them. But let’s assume Amelia is right what happens to Plan B? Well in Plan B, they can’t go through the wormhole and go to Edmund’s planet but they could still send embryos and develop them on a space station similar to what they show at the end of the movie (similar to the O’Neil cylinder). Of course this wouldn’t be as fun as Plan A.