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Is it possible for information to be transmitted faster than light by using a rigid pole?

Assume there is a long rod or a string connecting two points separated by a distance of several light years. It will take light several years to travel, but by a simple pull or push of the string or rod we can transmit date in binary format, what do you think?

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marked as duplicate by dmckee Nov 9 '12 at 14:21


thanks, got my answer! –  user461844 Jun 21 '12 at 9:40
Another identical question is physics.stackexchange.com/q/21122/373 . (Shameless plug of my own answer : you can even derive a quantitative bound on the elasticity of the rod/string from relativity physics.stackexchange.com/a/21123/373 ) –  Frédéric Grosshans Jun 21 '12 at 13:12

1 Answer 1

No, that's not true. The time it takes for the rod to move will be much slower than if you send a light pulse from one end of the rod to the other. The rod moves because all its atoms move in a certain direction. The speed in which the atoms move and signal for the others to move is much slower than the speed of light. It is counter-intuitive because most rods we are dealing with are SHORT.

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