It is impossible to travel back in time. Not all time travel is impossible; it may be possible to travel forward in time.
Well, despite the terrible movie, the butterfly effect actually teaches something: that a butterfly flapping its wings can change the world. For example, if you place a ball at the top of a hill, even by changing the position of the ball by one millimeter, it could take a completely different course.
Basically, if you go back in time, even by breathing and changing the carbon dioxide to oxygen ratio, you could make something breathe another gas that may have a disease. That something could die from it, setting off a whole chain of events, changing the world in the long run.
Another thing associated with the time travel is the grandfather paradox. If you go back in time, kill your grandfather, and then you would never be born, thus creating a paradox. The universe cannot have a paradox. It is unknown what will happen, but it is known (by known, I mean pretty well accepted) that the universe cannot have a paradox occur, therefore, it eliminates the possibility of the paradox by just removing the factor that causes the paradox.
The butterfly effect and the grandfather paradox are connected as if you alter the universe by being in the past.
Now, one way to get around this is that by killing your own grandfather, you form an alternate universe, parallel to yours. It would be impossible to get back to the other universe as you would have to go back in time to where the skew occurred, but as discussed with the butterfly effect, it might create a universe parallel to the parallel universe.
Another solution is that somehow, your grandfather is still alive, even if his head was chopped off. It would be impossible to conflict the the determined outcome of time. That leads me to the question if it is impossible to conflict the the outcome of time, then you why would time travel be possible in the first place?
Just something to think about. If any of you can come up with a solution to travel back in time without a paradox, I will be amazed.
I think that, if it would be possible in the future to travel through time, and the future people tried to hide it from the present people, it'd only be a matter of time (teehee) before someone screwed up and got discovered in the past (past for the future people, present for us), and we would know about it.
But then again, maybe they sent someone back to fix that screw up... But if the person screwed up in the first place, then we'd know about time travel by the time we could do it, and we wouldn't need to go back and hide that fact from ourselves, and thus we would not send someone back to correct the mistake...
Anyways, I'm confusing myself. What I'd like to say is that, even if we could travel in time, I'd say we should try not to. We'd seriously mess up everything if we did. The only thing it could be used for, I guess, would be to dump garbage so far into the future, the world will have ended by the time it appeared anyway.
If the philosophy of Determinism is true, than Time Travel doesn't matter, because all our actions have already been programmed into us by various factors, and everything has been scripted.
Just thought I'd throw that out there. I'm not saying that I believe it, or that you should believe it. Just another take on the idea, combined with something I learned today.
While I believe in determinism and that it is theoretically possible to predict the future, I don't think we will ever be able to precisely predict the future and so we can behave as if determinism is false with regards to free will and take free will for granted.
I don't think we will ever be able to precisely predict the future
We won't be able to predict the future for a variety of reasons - the Heisenberg Uncertainty principle being one; another being the fact that there is a limit to the observable universe - if we are not at the location of the Big Bang, then we will not be able to see the whole universe. Also, the time it takes for light to travel makes it impossible to tell what is happening on other stars right NOW.
But suppose there was a "being" who looked at the universe, and he could calculate much faster than time moved - this being, which is unable to become in contact with the system itself, could, perhaps, accurately predict the future of that system.
This is the only prediction of the future that is possible, since predicting the future requires (to some extent) for future actions to affect the past (think Newcomb's problem).
Time travel is possible into the future. In fact most of us do so every night by sleeping. Time travel into the past can also be possible only if the time travel does not affect the future that you came from. (For time travel into the past it is theoriezed that you need to travel faster then light) The problem is that you would not be able to go back into your future. There are also worm holes (holes in spacetime) and the unknown black holes (which may cause tears in the spacetime) hopefully that made some sense cause I need to go sleep now YAWNS.
Time travel into the past can also be possible only if the time travel does not affect the future that you came from.
I have to disagree. I dont think it makes a difference because technically that WOULD be the new future.
The problem is that you would not be able to go back into your future
Agreed. I think you would be going into a different future. Even then this is only possible if you can travel to another dimension but this would also technically mean you are not travelling into the past but into a dimension that, if almost identical to our own, would be further back. So still not really the past, just somewhere different.
There are also worm holes (holes in spacetime) and the unknown black holes (which may cause tears in the spacetime)
I guess these are our known unknowns.
I seriously think TT into the past in literally not possible because there is no such thing as "the past".
The hardest thing I can think of right now is how to explain this properly, so I too am going to sleep. Rar!
I've looked up every conceivable acronym with those letters and none of the relevant outputs (strokes per minute [swimming], steps per minute [walking]) would be even remotely close to approaching light speed, which would be the theoretical procedure to manipulate time.
Matt is indeed correct, but hey! Make another, because I love scientific threads in this forum.
