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It is said that if we travel at the speed of light,we will go into future,please could you explain how?Is it possible to make a time machine ever? Please give an easy answer, a simple one!

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marked as duplicate by Emilio Pisanty, Qmechanic Sep 8 '17 at 16:00

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    $\begingroup$ If I stand still I keep going into the future as well. We all travel through time... $\endgroup$ – Jon Custer Sep 8 '17 at 15:04
  • $\begingroup$ I meant how can we go into future before others do!! $\endgroup$ – user168498 Sep 8 '17 at 15:06
  • $\begingroup$ ?Is it possible to make a time machine ever? Please give an easy answer,a simple one A simple answer, but a possibly wrong one, is to say that a time machine is not possible. Currently, we don't have either the technology to build one, nor a definite, proven (or generally accepted) idea of how we could build one. $\endgroup$ – user167453 Sep 8 '17 at 15:19
  • $\begingroup$ You can go to the future, but you can never return. $\endgroup$ – safesphere Sep 8 '17 at 15:44
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If we travel at the speed of light, in our reference frame, time will slow to a halt. Therefore, seemingly no time will pass for us while for others time goes on. This means it will appear to us as if we have travelled into the future when we stop, as everyone else has carried on. Mathematically, it is possible to go back in time. If we travel faster than the speed of light, time will start to go backwards, allowing to travel back in time. This all due to special relativity.

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  • $\begingroup$ The part about traveling faster than light reversing the direction of time is false (There is no sensible extrapolation of special relativity to when an observer moves faster than light, as far as I know. If you take it literally the proper time elapsed becomes imaginary, not negative.) However, something moving faster than light according to one observer will look like it's moving back in time to some other observer moving relative to the first. So if you could send signals faster than light you could send messages back in time. $\endgroup$ – spaceisdarkgreen Sep 8 '17 at 18:40

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