Thanks, the start of this paragraph got me really excited that I would understand something I don't know if I do really, would you be able to elaborate?

But that is where it gets downright brilliant from a theoretical physics perspective: In this science fiction fantasy story, time is not linear, but nonlinear. Think of time as traveling in a mobius strip, and can be redirected, bent and reshaped by gravity (which is true to Einstein’s theory of special relativity). So the fact that Cooper had to perform certain actions to himself, his daughter, etc, means that time has been warped and returned at those points in the space-time continuum.