Nothing is faster than Light, Right?

AI Thread Summary
The discussion centers on the concept of transmitting a message through a rigid rod, suggesting that pushing one end of a 1 light-year-long steel rod could convey a message faster than light. The argument posits that if one end is nudged, the entire rod would displace instantly, seemingly violating the speed of light limit. However, it is clarified that the signal actually propagates at the speed of sound within the material of the rod, not instantaneously. Participants are encouraged to reference the FAQ in the Special & General Relativity forum for further clarification on this topic. Ultimately, the discussion highlights misconceptions about speed limits in physics and the nature of signal transmission.
Algren
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First of all, let's consider that this question is asked before neutrino's speed was discovered.

" Let's consider a rod, a rod which is as long as 1 light year.

Consider that it is a rigid rod of steel with diameter 1m (to prevent bending)

I gave a nudge to it from one side, then the whole rod will displace, right?

For example, i pushed the rod by 1m, then the rod will move 1m, right?

Ohh, look what happened! Something went faster than light! A lot faster! "

If you didnt get the above case, ill explain what happened:

I used the rod to send a 'message' by pushing and pulling it. Hence, it traveled faster the speed of light, since it conveyed the message through 1 light year almost instantly.

If you disagree with the above, give approximations of the speed of the message, if its not faster than 'c'.
 
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Please read the FAQ in the Special & General Relativity forum about this question. The signal propagates at the speed of sound in the rod.

https://www.physicsforums.com/showthread.php?t=536289

.
 
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