Faster than light communication

AI Thread Summary
Pushing one end of a solid rod does not result in the other end moving instantaneously; instead, the impulse travels at the speed of sound within the material. Even if the rod were extended between two distant space stations, the signal would still propagate slower than the speed of light due to the physical properties of the rod. The discussion emphasizes that while the speed of sound in steel is fast, it remains significantly below light speed. The concept of faster-than-light communication through a solid rod is therefore not feasible. Understanding the limitations of material properties clarifies misconceptions about instantaneous movement in solid objects.
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Say I have a solid rod of steel and I push one end, does the other end move near instantaneously?

As an extreme, say I had a solid rod extending from two space stations very far apart, if I pushed the rod perfectly perpendicular to the face of the rod, would the time difference between when I pushed the rod and when the other end of the rod moved be less then it would take a beam of light to travel between stations(faster than light communication)? I know there is stretching and compressing that would occur but still...

This might be a stupid question, but I just thought about it and wanted to get an answer?
 
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Any impulse you send through any rod will travel at the speed of sound in that rod. While that may be thousands of miles per hour, its well below the speed of light.
 
I thought that would be the case, oh well. Thanks for the assistance
 
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