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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?

+ 0 like - 0 dislike

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, 2021 in General Physics by Parzival (0 points) [ no revision ]
recategorized Oct 30, 2021 by Dilaton

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, 2021 by jeremyrutman (0 points) [ no revision ]
+ 0 like - 0 dislike
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 Oct 23, 2021 by anonymous [ no revision ]

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