Materials and particle coupling

[Ondra Spilka]

Hi,

since I don't have exact knowledge about materials and particle coupling, I want to ask for result of simple experiment:

imagine you have very tough stick 10 meters long. Let's say the stick is fitted on firm steel table in sliding blocks. Table is equipped with actuator strong enough to shift the stick, which will push one end of the stick. On the second side of teh stick in very small distance is detector, which will detect the stick contact.

So how fast will be information transferred from actuator to detector (let's say by push we transfer 1/2 of a bit)? Of course it depends on velocity of actuator shift, distance between detector and second side of stick. This is known.

But how fast the change of space coordinates on one side of the stick will appear on the second side?
How fast inbetween joins of atoms can react? Are they also limited by relativity limits?


Thanks for answer.

P.S.
try length of te stick 10meters, distance between detector and stick 1um, actuator velocity 30m/s.

 

[Mr.Brown]

Hmm i think the actual calculation would get rather involved because you would have to know the actual properties of the material to construct some kind of stiffness tensor then go on constructing a stress on that whole thing and whatever there may come better ask an engineer :)

But from a general point of view the whole thing is surely limited by relativistic principles.
Would be the same thing if you hand some kind of enormously long rod of steel say 1 LY long an you push it on one side, the effect would still take more than one year to propagate to the other side, maybe as some kind of wave in the material i guess.