Is time travel possible. In finite space?
355289
it is believed by many time travel is not only possible but that it has all ready begun. look up time traveler john teeter or it may be john titor .tell me what you believe the truth is that you see
18327
If you would belive in the parallel universe theory\nthere is a possibility that the past exists in a \nanother parallel univerese.However if you would\nbelive in the space-time continum,the past would\nnot simply exist as would the future.But theoriticaly\ntime travel is possible is you consider slowing down\nthe rate of time advancing but this will not lead you to the past but it would take longer you to reach the future in your particluar reference of time\n,here relativity comes into picture and the solution is still not clear.
692266
It is an open question of physics, whether it is possible to travel backwards in time. No one knows yet.\nhttp://en.wikipedia.org/wiki/Time_travel\n\nBut it is known now that it is possible to travel forward in time faster than normal, you just should move around very quickly, close to the speed of light. That is called the Twin Paradox.\nhttp://en.wikipedia.org/wiki/Twin_paradox
1011227
Love to give you specifics, but don't know how.\n\nTheoretically, what you suggest is possible by relativistic theory. There are things called "tachyons" which are these kinds of rays which reverse time - well not "reversing" it, but definitely messing it all around.  Einstein said that nothing could accelerate to faster than speed of light without becoming infinite mass - but "...Einstein said nothing about entities already traveling at that speed or greater..." (Prote in K-Pax).  \n\nSo who knows - is it around the corner for us?  Probably not.  Is it possible?  I love this universe, so I say yes.  Keep surprising me...
965397
Travelling back in time is not allowed by einstein's theory of relativity...however if you can instantly teleport youself to some faraway star,say a 101 light years away, you might be able to catch einstein receiving his nobel prize!! as stated earlier, there is no master grandfather clock that is regularly ticking away the seconds..rather that rate is adjustable...but one may zip into the future..consider an example where you are on a space-ship at a speed of 0.99990 c that is going away from the earth and coming back..in your time frame say,it takes about twenty years..using lorentz transformations, the time for your to and fro motion is close to 450 years!!
11171
yes, traveling forward in time is definately possible, but we're not sure about back.  This has nothing to do with wormholes or anything, that probably wouldn't work.\n\nanyway, velocity distorts time. The faster you go, the slower time goes for you. This effect is negligable unless you are going very close to the speed of light. In fact the formula is:\nt'= t/sqrt(1-v^2/c^2)\nwhere t' is the time that has passed for a stationary observer, t is the time that has passed for you, sqrt means square root and ^2 means squared. As you can notice, when v is small, since c^2 is so huge, you get a miniscule decimal, and 1 minus that number is basically as small as .999999999999999 or something very very close to one, and so t' stays basically the same as t and time is not really affected. As v gets larger(it can never be the speed of light, then the denomonator would be zero) that fraction becomes closer to 1, so when you subtract it from one, the denomonator gets smaller and smaller, meaning t gets smaller(in order for t' to remain constant) this means that time slows down for the object moving at such velocities! time slows down, so it would feel like lets sayThis formula is correct, it is part of Einstein's theory of relativity, and I have had to derive it myself from ordinary mechanics formulas. \n\nThis proves the formula:\nAccording to the same factor, length also contracts. It has been observed in certain tiny particles coming to the earth's surface. These particles have a certain lifespan before they become unstable and decay. They are also moving at a certain speed. (which is very fast; close to the speed of light.) You should simply be able to calculate v=d/t (velocity=distance/time) to find out how far they would travel. However, they somehow travel farther than that. When this calculated distance is put into that formula, we come up with the correct distance they actually travel! \n\nSo yes, as you get faster and faster, since time slows down for you, theoretically, you could be moving at these speeds for a short time and time will seem to be moving normally for you, but have years and years pass for everyone else, thus traveling forward in time. As far as back in time... well, if you think about it, if things travel slower and slower the closer you get to light, does that mean it would stop when you reached it? and what would happen when you went faster, would it go back in time?  the only problem with this is that nothing can go faster than the speed of light, which has been considered "the ultimate speed limit of the universe."  Plus, if you were to go faster, the v^2/c^2 would be greater than one, meaning you'd get a negative number after subtracting it from one and have a negative number under the square root in that formula.  This is impossible.  Also, the problem with even traveling forward in time is that it would require immense amounts of energy to accelerate objects that fast.  It requires particle accelerators miles long just to get small sub-atomic particles to go that fast, imagine massive objects, it would be crazy. and distorting time by any reasonable amount would require going at least 90% the speed of light.. probably faster.  The closer you got to the speed of light, the more time would slow down for you.\n\nThere are also some other methods described in the book "time travel in einstein's universe" by Richard Gott, if you're interested.
1152446
Well this one is interesting.  Mathematics tell us that to move in time, one must move faster than the speed of light.  There are particles that do move that fast so it is theoretically possible.\n\nWith that having been said, I'll go back to the particles that move faster than light.  These particles cannot be seen or measured in any way that we can figure out but we know that they exist because of the reaction of other things.  ( its like the wind blowing,  you dont see it but trees and stuff react to it )\n\nOne theory suggests that if we do manage to travel back in time,  we wont be able to interact with it at all. ( I dont understand all the mechanics on this one)  But it would be like being an invisible ghost.  You could observe things and events but couldnt make actual physical contact with anything thus you couldnt change events.
589080
I don't accept the premise that a time machine is possible, therefore I can't answer such a question, even hypothetically. I can give you a proof that time travel into the past is impossible. It goes like this. If time travel into the past were possible, then at some time in the future, the means to travel into the past will be developed. That being the case, then we could expect to have been visited by time travelers from the future, but we have not. Ergo, time travel into the past is impossible. However, time travel into the future is possible. From the time I started typing this answer, up to now, I have traveled into the future about two minutes. However, it is still now. It is always the present. Always and forever.
222343
you can travel to the future but not the past, the closer you travel to the speed of light the faster the time goes by on the outside. I once knew how this worked but can't rememeber now.\n\nIn order to travel through time, one must travel at the speed of light, or at least at speeds very close to the speed of light. The problem is, as you mention, that it is not possible to accelerate something up to the speed of light. This comes from the theory of special relativity. In that theory, Einstein has shown that as something accelerates and travels at great speeds its mass increases. And the larger the mass of the object, the harder it is to give it a push to make it accelerate some more. So when the speed of the object gets really close to the speed of light, its mass becomes almost infinite making it impossible to actually give it the speed of light (or speeds faster than the speed of light). \n\nBut you don't need to travel exactly at the speed of light to "travel to the future". This also comes from Einstein's special relativity. When things travel at speeds close to the speed of light, time slows down. For example, if you were travelling for 10 years in a spaceship that could go at 95% the speed of light then 32 years would go by for the people that stayed on Earth. So in that sense you could say that you have traveled in the future. However we do not have the means to accelerate our space shuttles to speeds even close to that. The space shuttle travels at about 17,500 miles per hour which is 40,000 times slower than the speed of light. At that speed, an astronaut would have to travel a billion years in his space ship in order to jump one year in the future!
630252
Teleportation. We at least have theory on how teleportation could work. If the universe under discussion permits of time machines, then no time machines will be invented. The noted s/f author Larry Niven wrote a couple excellent essays on these topics, which I recommend to your attention. They will provide all the information you could possibly need.
519456
There are some strange solutions to Einsteins field equations which some theorists claim to offer the possibilty to travel backwards in time but these are pure hypothesis.\n\nFor one of these possibilties you would need a huge amount of "strange matter" which we yet even don't know what it is exactly, other of these hyothesis would allow to travel back in time, but not past the invetion of the thime machine, since this time machine is the "exit" on the other side of the "time tunnel".\n\nOther scientists say it will never be possible, for varios reasons, one of the most mentioned is the problem with causality (althogh there are again theories that that would't be a problem) another very funny one is by Stephen Hawking: There never will be time machines, becaus if it would we would see tourists from the future all the time.\n\nSo, seriuosly, don't expect to see a working time machine during your lifetime.
720083
well its theoretically feasible to go forward in time but not backwards, but with today's technology its not very doable.
70282
No.  You'd need to have a wormhole.  Current theory predicts that transversable wormholes exist but would not allow time travel.  See reference for details.
50535
OK, first fo all Mr cliffx has it backwards.  As you continue to acellerate tworads the speed of light time will slow down for you and stay normal for everyone else.  Thus at that speeds you could travel 10000 lightyear in only 1 year, your lifetime, but thousands of years could pass on earth.\n\nIt has been theorized that time travel is posible but you could not simply accelerate to that speed.  Even if we could travel that fast the economical need would be currently beyond what any country has, even if they put all there funding into that one project.  but I am getting off the subject.\nOne theory is to travel into a black hole.  The gravetational field in a black hole is so strong that it has been theoryzed that even time cannot escape.  Thus if we were able to travel into a black hole we could use the captuered time there, so to speak, and transverse the timeline.\n\nThen there are ideas of actually traveling on light waves, lasers, to allow us to travel to the speeds necisary.  Of course then we could only travel to the time of how long that peice of machinery is on.  Also we would have to convert ourselvesinto an electrical signale, data (essicially transport), which would then bring up the promblum of measuring matter without moving it and blah blah blah.\n\nSummery, Yes it is possible to travel through time.  We just do not havet he knowledge and/or technology to do it yet.
1131993
My opinion is that in order to travel through time we would need to be able to travel uncalculable extraordinary distances.\n\nImagine how fast the earth is moving through space. Not only would we need to calculate the speed of the Solar System; but the speed of the Milky Way Galaxy; the speed of the Universe; and in which direction.\n\nWhy would we need to know this? We would need to be able to travel to the actual physical position in which the Earth would be located at the time in which we were desiring to be present.\n\nIt is my opinion that if it were not for the fact that we are traveling at such and such a speed that "Time" itself would not be possible in the first place.\n\nThe fact that physical matter is never in the same location;;;EVER;;; is what I believe makes the existance of matter a possibility.\n\nImagine that if the Earth were a hundred miles away from its current location in just one small second of time. To travel back one second in time you would have to travel that one hundred miles of distance.\n\nWould the Earth be there if you could travel that distance? Some scientists want to believe that "worm holes" can link up huge distances in space by folding or warping space, distance, and time. \n\nI personally believe that God has the power to time travel; or how else could he know the future in order to prophesy; and I do believe he has proven the ability to prophesy. Yet, did he time travel, or did he make things happen according to his prophecy?\n\nOk; if God exists in the future; or at the end of time (the furthest point in which time has yet reached since the beginning of all time) and has the ability to travel back into various points of the timeline; he then has the ability to travel forward and backward in order to see how well things are going according to his own actions.\n\nSo then, Jesus would have seen everything before it ever happened. I also take into account that God must have the ability to be larger than the Universe and smaller than the smallest forms of energy and matter if he were truly capable of producing and controlling them.\n\nYet affording us free will is what allows us to be who we are.\n(see references below)\n\nIs it possible that matter is frozen in time at every location along the path of which it travels? In other words; Is our history preserved as if it were a tape or recording throughout all of its existence? It does not seem possible; but anything is possible with God. Maybe this is where the "Missing Universe" energy is located; frozen in time. If this were true than I believe it may be possible to time travel. One would have to have the ability to travel amazing distances at amazing speeds.\n\nI would have to believe that traveling into the past would be possible under the circumstance that matter becomes frozen in place as it travels and that a person could travel such distances and had much time available for the journey.\n\nSo if traveling into the past were possibe; because the past would be there; whereas the future may not be yet, would traveling into the future be possibe?\n\nAfter traveling backward, surely we could then travel back to the future from where we just came from. This theory would conclude that we exist in the "real" present and the future really has not happened yet.\n\nSo traveling into the future could only happen if we first traveled back into the past, and then went back to the future.; where we came from.\n\nSo lets say someone else traveled back from the future (which has not happened yet to us; because at which point do we cease to be the "real" point in which time has already existed?) into our present time. We would have to consider that if God really does prophecy by time traveling, then we do not currently live in the "real stream of time"; but time and history has already taken its course and has already been fulfilled.\n\nIn other words; we do not live in the real present; but
1001554
According to Einstein and Stephen Hawking, travelling at the speed of light (for anything with mass, ie not photons) is impossible.  But travelling near the speed of light is theoretically possible.\n\nIf you were to travel close to the speed of light you would go into the future a lot quicker than those who don't travel close to the speed of light.  It would require huge amounts of energy.\n\nUnfortunately it would be a one way system.  To travel back it time it would be necessary to bend the whole universe.  Or you could find a way of travelling to parrallel universes (if they exist) and that would solve problems for both forward time travelling and back time travelling.
1186042
That's the problem. You can't go beyond the speed of light. It is the cosmic speed limit. But if you could, then you'll be able to travel through time, past and future.