|MadSci Network: Science History|
Ever since Einstein revealed his special theory of relativity, we've known that time travel is possible.
Einstein didn't pull this theory, or even the notion that time travel is possible, out of thin air. Rather, he took the knowledge of the day, saw an inconsistency, a piece of a puzzle that didn't fit, and thought about possible explanations.
According to the equations of Einstein's theory of relativity (the best theory of time and space we have), there is nothing in the laws of physics to prevent time travel. It may be extremely difficult to put into practice; but it is not impossible.
Now, how to explain it! Well, to put it simply, for things that move, time runs slowly! So if, for example, you had a twin, and you left them behind on earth, while you went space travelling. On your return you would be slightly younger (than your twin)!!
If you want to get a greater understanding; I recommend looking at this website:
Hope this helps!
Rhyl, Wales, United Kingdom
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