What a sick movie!

Einstein's ideas like Einstein-Rosen-Bridges (the technical term for wormhole) were suggested, as well as travelling at the speed of light slows down time for the traveller due to the theory of relativity. The thing is neither of these are at work in Predestination. Ideas like gravity's effect on bending and slowing time via black holes are explored in things like Interstellar. This isn't either a wormhole portal, like in The Terminator movies. The problem with a wormhole is you can create feedback, like when you put a speaker too close to a microphone at a music concert. Energy such as light, and in particular radiation would go through and would build upon itself, possibly leading to something like a nuclear explosion. This has been suggested by Stephen Hawking to be a reason why no wormholes from the future have appeared in our time or before. The time travel used in this device seems to be like almost a hyperlink, it takes you from points XYZ (the basic 3D axis of space) plus the destination of time. Ok that's the science done.

Why something is sick, is as you could say due to subjective experience or focus on a particular object due to some obsession or attraction or embedded repulsion due to trauma or the construct of one's psyche. The film is based off a short story written in 1958 by Robert A. Heinlein. He liked exploring philosophical ideas of time travel such as what's now called The Bootstrap Paradox based on his By His Own Bootstraps 1940s short story about time travellers constantly interacting with each other in an impossible way. He also had ideas about militarization in Starship Troopers, and ideas on sexuality and spirituality in Stranger in a Strange Land. He liked exploring ideas, this is an ideas film, which uses the idea of Predestionation, which is "whatever happens in this timeline happens in this timeline, and there's no changing it", also known as a closed timeline, like in the first Terminator Film, before the sequels started changing the timeline, as suggested in the Back to the Future films, in which the timeline is alterable or what is called an open timeline.