Thread: Backward hearing

Theory has it that if you travel faster than the speed of light (which theory has it is impossible) then you will travel back in time.

Does this mean that if you travel faster than the speed of sound, then everything you say to a stationary observer will appear to have been said backwards?

Such as going at mach 2, saying "hello" will appear to be said "olleh"

If so, what is the science behind it?

Discuss!

Originally Posted by asxz

Theory has it that if you travel faster than the speed of light (which theory has it is impossible) then you will travel back in time.

This is pure speculation, not theory. There is currently no evidence that you can travel faster than the speed of light by normal means. Similarly, time travel (in the sense of going back in time) is equally implausible.

Such as going at mach 2, saying "hello" will appear to be said "olleh"

Maybe if you're catching up to it so the first sound wave you receive is the last one out of the stationary persons mouth, but you wouldn't hear it anyway.

YOu can indeed hear sound 'backwards' at least in theory, suppose you shout something out that takes a second to say, then travel at twice the speed of sound for one second, you will catch up with the sound waves you made, in reverse order. Of course acceleration to Mach 2 in zero time flat in order to achieve this, might cause a litle physical stress, the sound waves would be attenuated to a point where you would not hear them, your sonic boom would upset the experiment etc etc...