from a bbc documentary, from bits and pieces that i know of physics, from science fiction novels, and some loose ends from philosophy:

one of the implications of the general theory of relativity is that time and space are just two sides of the same coin (not sure if the analogy is correct). this means that you can treat them as two very similar things. the way space stretches is a bit like how time stretches as well.


Figure A

in figure A, objects in space all exist together at a certain point in time. you, standing on the street exist at the same time as the house exists and the tree exists and the earth exists and the galaxy exists. you might be in different places but you all exist together. you can move towards the tree or towards the house or suddenly teleport to another planet but still all the other things will still be there in space. if the general theory of relativity is correct, the same should apply to time.


Figure B

if time has the same property as space, that means all past instances and all future instances exist together. the person you were yesterday exists as real as the person you will be tomorrow as real as the person you are this very moment. you can therefore think of the future as a place you are headed for, like you are headed for a tree; just because you havent gotten there yet it doesnt mean that it doesnt exist yet, meaning (if i understood the bbc docu right) the future already exists! and by corollary, the past STILL exists, just as the tree still exists even if you move away from it in space.

this has many interesting implications:

a) time travel and clairvoyance are both possible in a universe that follows the general relativity model

and

b) the universe is deterministic; the future is already OUT THERE. meaning you can't really change it, its already been set since time and space evolved from chaos

if somehow that depresses you, there is some relief offered by the OTHER big theory in physics, quantum theory. in the quantum universe, when you get to the very very small small tiny tiny particles of things, it seems that things are so very NOT deterministic. they actually random, chaotic. there is no predicting where this piece will be in the next millionth of a second. it could suddenly be somewhere else. everything suddenly becomes probabilistic instead of being set in stone. the happy thing about that is that there might be some way quantum randomness affects human beings so that in the end our choices are entirely free, random, nothing pre-determined

the strange thing is that physicists seem to find that BOTH theories are true, so far. how can that be? i dont know, but scientists and philosophers are trying to reconcile the two together. could it be that they could find a way to marry the idea of FATE and FREE WILL? too bad none of my friends chose to be scientists or philosophers. things like these are great with beer and peanuts


D demonstrating the concurrency of his two past selves