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  What happens if an object falling in vacuum(disobeys the general theory of relativity), falls faster than the speed of light?

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5477 views

I know the question sounds crazy enough to laugh at. But what if it happens? Feel free to criticize and give some astounding answers!

asked Oct 6 in Theoretical Physics by Parzival (0 points) [ no revision ]

2 Answers

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There's a problem of getting 'over the fence' - to reach the speed of light you need infinite energy - in special relativity you have a 'gamma' factor which goes infinite when v=c  .
And it gets weird from there, the energy amongst other quantities goes imaginary if v>c.   Possibly such things could exists from the get-go and thus wouldnt have to cross the v=c barrier, the idea is called 'tachyons' but I blv. no evidence exists for them and its not clear if these should be detectable.

answered Oct 20 by jeremyrutman (0 points) [ no revision ]
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There will be a kind of Cherenkov effect as in all physical media where the speed of
 the particle exceeds the speed of light. 
answered 5 days ago by anonymous [ no revision ]

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