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Is it possible for information to be transmitted faster than light?
I've thought about this since I was a little kid. I know it isn't exactly feasible, but it still bothers me.
I hand you a really long wire, and we agree that "a long tug means 1, two short tugs mean 0", then you move off into the galaxy, a few light-years away from me. I proceed to give you information by tugging on the wire.
With a really tight wire, couldn't I talk to you faster than the speed of light?
In theory you could not: information can't go faster than the speed of the light.
The movement along the wire would not happen at the same time along it. It would start from the side of the mover, and would propagate all around its source. At which speed? well .. it depends on the elasticity of the material the wire is made of.
A funny note is that when you film your moving wire and then replay the video at a very slow speed, you will notice that all types of matter appear to be somehow elastic.
I think the question was about transverse and not longitudinal waves. In case of transverse waves the wave velocity - speed of crests - goes with square root of tension/linear density ($v^2 = \frac{T}{\mu}$) and is therefore theoretically possible to be infinity for every material (large $T$, small $\mu$). However, velocity of information is still smaller than velocity of light.
In particular, imagine that you started wave at one end of the resting wire. The beginning of disturbance would surely go slower than velocity of speed, but speed of individual crests could go faster than that. It would seem like if crests keep bumping into the start of disturbance and disappear. Hard to imagine, but I've tried to explain.
