Is Time Dilation the Key to Understanding Time Travel in Science Fiction?

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Hey I just found a wiki post about time dilation and I was wondering if its correct


Science fiction implications
Scientist and science fiction enthusiast alike, quickly realized that the effects of time dilation make time travel a plausible notion. People typically thought time was linear, and equally relevant to each observer. The pre-general relativity view was that time travel would involve changing one's position on a supposed linear time-line. It has since been established that time and space exist as one, hence spacetime. In theory, if you build a mechanism that moves at a great speed with an observer inside, time will pass the observer slower than it does to those who are Earth bound. Backwards "time travel" is also theoretically possible If you exceed the speed of light. Though, to even reach the speed of light one must have 0 mass.
 
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The bit about 'forward' time travel while moving close to the speed of light relative to others is correct (and a confirmed concept in physics). The bit about backwards time travel is speculative at best.
 

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