I’m not a physicist but I know enough to know that time-travel, if you’re going into the future, is possible, and that going into the past is not. It’s the violation of the old ‘cause and effect’ principle which makes backwards time-travel a no go. Now I wish I was a physicist because Interstellar suggests that interacting with the past is “theoretically” possible so long as higher dimensions are used to bridge the gap between present and past.
Well, at least that’s clear.
The premise is straightforward: the earth is becoming slowly uninhabitable for humans and measures must be taken. A wormhole has been discovered in orbit around Saturn and the plan is to fly a ship through it to see if any of the planets in this new galaxy are able to support human life; if so, we all pack our bags and ship-off to the new planet, saving the human race.
It doesn’t go smoothly – but who would want it to?
Finding higher dimensions is a simple task. All you have to do is discover a direction which is at right-angles all at once to the three we know about: up/down, forwards/backwards, left / right. What’s so hard about that? Once found, a person residing in that higher dimension could put their hand inside your body and manipulate your organs without breaking the skin. Just as we, residing as we do in three dimensions, could put our hand inside a circle without breaking “the skin” of the circle. That poor circle is suffering down there in a two-dimensional world. To be one dimension up is to have a significant advantage.
The physicist who worked on Interstellar said he went so far as to work out the equations for how the star-light would trace across the view of the person flying into the wormhole. That’s okay by me for what do I know? The problem for me is the interaction with the past which is supposedly possible.
Matthew McConaughey manages to interact with his daughter from his higher dimension by knocking books off her shelf in her bedroom. We see this at the beginning and she thinks she’s got a poltergeist haunting her. Come the end we learn it’s her father, in his higher dimension, trying to communicate with her. That’s what I don’t understand. You know what, forget ‘interacting with the past,’ I’m confused just about interacting across dimensions. To knock books off the shelf is the same principle as looking at a circle drawn on paper and peeling the circle up from the paper: We couldn’t physically do something from our third dimension and make a physical change on a two-dimensional object.
If there are any theoretical physicists or mathematicians that could offer help I’d appreciate it.