Time travel when velocity> light speed

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shredder666
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Not sure if this will have anything to do with quantum mechanics.. but...
Ok so if you're traveling faster than light speed, then what do you see?

I'm not talking about the whole doctor who scenario, its like traveling faster than sound, if the jet pilot is traveling faster than the sound it makes, then he/she wouldn't hear that sound. Would this be of a similar case with your eyes?
 
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shredder666 said:
Ok so if you're traveling faster than light speed, then what do you see?
No massive body can travel faster than light, so the question isn't meaningful in light of current physics.
 
shredder666 said:
Not sure if this will have anything to do with quantum mechanics.. but...
Ok so if you're traveling faster than light speed, then what do you see?
There are hypothetical subatomic particles which travel faster than c. As a group they are called tachyons. Just like our sublight particles cannot ever reach or exceed c, tachyons can never slow down to or slower than c. This means they are forever cut off from our universe.

That being said, a tachyon is equivalent to a regular subatomic particle traveling backward through time.

It won't do you much good though, since they still do not violate causality. Wiki has a note on http://en.wikipedia.org/wiki/Tachyon#Causality".
 
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Remember also that at speed .99999999999999999999999999999999999C an observer STILL measures light at speed c, and color from a light source in his reference frame is normal (ok for reading a book).

But at such incredibly high speed, light coming toward you from opposite the direction of your velocity appears shorter in wavelength and light coming from the rear direction is looooooooooooonger in wavelength...relative to a "stationary" source...both out of the range of visible light. You can check out such effects by looking at references for red shift and blue shift...
 
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