Time Travel - is it possible?
Discussion
in a time machine sense?
The Grandfather Paradox, and the probability that no-one from the future seem to have visited us suggests there could be a few issues with time travel, at least backwards, but a couple of random boredom generated musings:
1) Going to the future. If we could measure to a very precise degree everything there was to measure about the physical characteristics of a roulette wheel and ball at the moment of the ball's release and had a fast enough computer, we could fairly easily work out the winning number before the ball stops rolling, yes? The same for lottery balls. Because the winning number is not something really random, but the inevitable and calculable consequence of the physical properties of the relevant factors at play.
Similarly, at vastly larger scale, everything that happens in the future to anything is an inevitable and calculable consequence of the current state. Even 'free will' is determined by chemicals and electrical impulses in the brain. Thus, if we could know everything there was to know about today, we could calculate what happens in the future.
In the roulette example, as soon as the ball is released, we can predict what number it will stop at. So there is no need to wait for the ball to fall. We could jump 'to the future' and save the waiting.
2) Going to the past. If we were on a planet one light year from the Earth, and looked back through a telescope at our planet, we would see the past as it was one year ago. If we had a vehicle that traveled faster than light, we could travel back to the earth, along the light coming towards our telescope, and reach the Earth before the light we saw had left it. And we would have gone back in time.
Or maybe not.
The Grandfather Paradox, and the probability that no-one from the future seem to have visited us suggests there could be a few issues with time travel, at least backwards, but a couple of random boredom generated musings:
1) Going to the future. If we could measure to a very precise degree everything there was to measure about the physical characteristics of a roulette wheel and ball at the moment of the ball's release and had a fast enough computer, we could fairly easily work out the winning number before the ball stops rolling, yes? The same for lottery balls. Because the winning number is not something really random, but the inevitable and calculable consequence of the physical properties of the relevant factors at play.
Similarly, at vastly larger scale, everything that happens in the future to anything is an inevitable and calculable consequence of the current state. Even 'free will' is determined by chemicals and electrical impulses in the brain. Thus, if we could know everything there was to know about today, we could calculate what happens in the future.
In the roulette example, as soon as the ball is released, we can predict what number it will stop at. So there is no need to wait for the ball to fall. We could jump 'to the future' and save the waiting.
2) Going to the past. If we were on a planet one light year from the Earth, and looked back through a telescope at our planet, we would see the past as it was one year ago. If we had a vehicle that traveled faster than light, we could travel back to the earth, along the light coming towards our telescope, and reach the Earth before the light we saw had left it. And we would have gone back in time.
Or maybe not.
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