It can look dumb, but I always had this question as a kid, what physical principles would prevent this?
I enjoyed a lot of the discussion in the comments
The pole would basically be a space elevator. I suspect gravity and inertia would effectively keep you from moving the stick. Even if you could move it, you'd only be able to move it at a speed that would seem like it's stationary. As such, the light would still be faster.
You're gonna want a powerful laser probably and ain't no stick that big like not even fkn close not even if we tried so that's why would'nt tbqh
This wouldn't work because the moon is more than 300k km away :P
If you're openminded enough to listen to those who disagree with the standard model,
take an elastic band and turn one end. Instead of the band turning, you'll have a twist in your band
and it takes time to unravel the twist if you let go on the other end.
That's what will happen to the stick and this travels at lightspeed,
because this is how light works. Light works like 'the stick' in your example.
And if you try turning it faster the 'elastic band'/stick/'atom on the other end' starts breaking.
If you need FTL communication, then use gravity..somehow.
Perfectly rigid sticks don't exist.
What about the mass of that stick? Inertial doesn't care for your little silly games.
Neither do the two gravity wells the stick spans. And the earth and moon are moving relative to each other, someone would probably get their head knocked off by that stick. Before it eventually falls to the earth with quite a bit of force because earth's gravity well will win. Then it'll eventually settle into a giant teeter totter, assuming it is rigid enough to survive the impact.
I don't see this mentioned in any of the other comments: the repulsion between atoms that causes the movement to propagate through the stick is actually communicated via photons. So your push really generates the same kind of particles that your light torch is generating, and they travel at the same speed. Except in the stick it is slowed down by repeated absorption and excitation by the electrons of the atoms.
That would not work. Pushing an object is transmitting kinetic energy to it. The object will push back, and energy would not be distributed to the whole object at the same time.
If the object cannot be altered in any way, then the energy would not be transferred to it, and if it has enough plasticity to absorb the kinetic energy, it would be spread in a wave to the tip. A wave that would always be slower than light.
Now stop fooling around and give Ruyi Jingu Bang back to Sun Wukong.
Move a sheet up and down rapidly
You can see the wave travel across it
Your push would travel at the speed of sound in the stick. You could think of hitting a pipe with a hammer, the sound of the hit would travel at the speed of sound, same is true for you pushing the stick.
The issue is, that kind of stick wouldn't even exist. You'd have better luck with between some dwarf planet and its satellite, since the stick would break under its mere weight.
It's a thought experiment. Of course such a stick wouldn't exist. OP's question is what laws of physics prevent this theoretical scenario from working.
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