Instantanious communication (faster than light)

AI Thread Summary
The discussion centers on the idea of using a wire in a tube to achieve instantaneous communication by moving the wire back and forth. However, it is clarified that this method does not allow for faster-than-light (FTL) communication, as the movement of the wire generates a wave that propagates at the speed of sound through the material. The conversation references a physics FAQ that explains the limitations of FTL communication and addresses common misconceptions. Participants agree that while the concept seems simple, it ultimately does not work as proposed. The thread concludes with a recommendation to explore the FAQ for further information on FTL topics.
Gaz
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I have no idea where to put this and it isn't based on any theory's just common sense and is very simple

If you get a tube and put a wire in it make it as long as you want to and to pass information simply move the wire back and forth as the whole wire is moving at the same time the information transfer will be instant.

I'm pretty sure that this has got to work and doesn't violate any laws how could it it's just a wire in a tube
 
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I'm fairly certain we have an FAQ on this somewhere as it gets asked quite often. In any case this won't lead to FTL communication as objects do not move instantly when you push on them, it's difficult to tell with most solids but when you push on one end you send a wave propagating through the material. This wave travels at the speed of sound. If you imagine something like jelly it's more obvious, if you had a long tube of jelly and you flicked one end you'd see it ripple down the surface. All materials do this.
 
I see what you mean, I didn't think that it could possibly not work it's so simple =)
 
Hi Gaz, Ryan_m_b have already answered, and I'd like to mention this page:
"Is Faster-Than-Light Travel or Communication Possible? - 4. Rigid Bodies" (Baez Physics FAQ)
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/FTL.html#4

Furthermore, that page covers many more "faster than light" (FTL) topics (e.g. apparent FTL, commonly misunderstood examples and also some hypothetical topics).
 
I think that's a good place to end this thread. Thread locked.
 
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