Paradoxes such as these are generally hints that Mother Nature or the laws of physics have a problem with what we want to do and probably won’t allow it. However, when it comes to time travel the strange thing is that there seem to be no laws in physics to prevent it and even some that make it theoretically possible. Of course if you’d read my blog yesterday you’d know about my scepticism regarding science. They probably messed up somewhere and all the laws of physics are wrong anyway but let’s continue anyway.
The reason most of us look at these paradoxes and see a huge problem is that most of us don’t fully understand the way time works. It’s not simply the one way linear street, inexorably moving forward, that we all think it is. In reality it is far closer to the three dimensions of space we all see every day. It is the fourth dimension existing just as the three dimensional world around us. And in this world we are free to go back and forth as we choose, so why not the same for time?
In actual fact we all do a bit of time travelling every day. If you are in a moving car time actually moves slower for you then for a pedestrian. The difference is so tiny that we would never notice but it’s there. In fact the faster you move the more time slows down. If you were to travel at the speed of light time would almost come to a standstill.
But with speed we can only move forward in time, not backwards. So we have no problem with our grandfather paradox just yet. However, gravity also effects time and this is where things start to get really interesting. Even on our planet slight differences in gravity make a difference to time.
If you and a friend were to work in a tall building one near the ground floor and the other near the top, time would move at a different speed for the two of you. Of course the difference in gravity is tiny so it makes almost no difference, but out in space, there are things that begin to really mess with gravity.
Black holes. Once only a part of Einstein’s theory we have now found them. Black holes as we all know have gravity so intense that even light cannot escape. So what about time? Well before we get there it’s important to note another thing about Einstein’s theory. His theory sees space and time as dimensions as I have said but it also allows for them to be bent and warped. Of course it turns out to be gravity that does the warping. For the most part its subtle but around black holes things get really messed up. Black holes twist space and time so violently that it twists into a spiral, like the eye of a storm. Of course in terms of time travel, a black hole is useless, because there’s no coming back. It’s a one way ticket for probably a very short ride.
Another possibility thrown up by Einstein’s theories, though yet to be found is wormholes. Worm holes occur where space time folds over on itself and a black hole of sorts unites the two pieces. This is where time travel gets potentially useful. Theoretically you could enter the one side of the worm hole at one place and time and come out the other side in a totally different place and time. Of course scientists are yet to find a worm hole and there still are some other theoretical problems to with radiation killing anything trying to go through. You never know though, at one time black holes were a theory even thought ridiculous and impossible by Einstein himself.
Time travel is likely to remain fantasy for the foreseeable future and yet it is far more possible then most of us would ever realise. Physicists still haven’t found a law to prevent it so we might just one day be able to move back and forth in time as we do in space. Of course it’s just as likely that Mother Nature will chuckle silently to herself and find some way to strike down misbehaving humanity in some way.
If one folds space and moves against the fold and travels a positive distance in a negative space, wouldn't it be possible to move backwards in time in the universe you existed in?
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