It can look dumb, but I always had this question as a kid, what physical principles would prevent this?
this post was submitted on 11 Feb 2025
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You're pushing the atoms on your end, which in turn push the next atoms, which push the next ones and so on up to the atoms at the end of the rod which push the hand of your friend on the moon.
As it so happens the way the atoms push each other is electromagnetism, in other words sending photons (same thing light is made of) to each other but these photons are not at visible wavelengths so you don't see them as light.
So pushing the rod is just sending a wave down the rod of atoms pushing each other with the gaps between atoms being bridged using photons, so it will never be faster than the speed at which photons can travel in vacuum (it's actually slower because part of the movement of that wave is not the lightspeed-travelling photons bridging the gaps between atoms but the actual atoms moving and atoms have mass so they cannot travel as fast as the speed of light).
In normal day to day life the rods are far too short for us to notice the delay between the pushing the rod on one end and the rod pushing something on the other end.
Very well put.
Wat? I strongly believe you are not correct. Which is to say, I think you are talking out of your arse entirely. If you push on a thing you peturb the electron structure of the material. These peturbations propagate as vibratory modes modeled as phonons.
While technically some of this energy is emitted as thermal radiation that is not primarily where it goes. And phonons themselves propagate at a slower rate than the speed of light, a significantly slower rate. Like a million times slower.
And how do you think the information that an electrically charged particle is moving reaches other electrically charged particles...
My mistake, that's why sound travels at the speed of light.
It's just not useful to talk about this at the level of the standard model. We are interested in the bulk behaviour of condensed matter, the fact of the matter is that you will not be able to tell that the other end of the stick has been touched until the pressure wave reaches the end. It doesn't matter if individual force carriers are moving at the speed of light because they are not moving in a single straight line. You are interested in the net velocity.
Wikipedia isn't a textbook. Don't overcomplicate shit and mislead people because you've spent a few hours browsing particle physics articles stoned.
I very explicitly said the whole thing is slower than the speed of light (much slower even) and even pointed out why: at the most basic of levels, the way charged particles push each other without contact is the electromagnetic force, meaning photons, but the actual particles still have to move and unlike photons they do have mass so the result is way slower than the speed of light.
To disprove the idea that a push on a solid object can travel faster than the speed of light (which is what the OP put forward), pointing out that at its most basic level the whole thing relies on actually photons which travel at the speed of light, will do it.
There was never any lower limit specified in my response because there is no need to go into that to disprove a theory about the upper limit being beyond a certain point. (Which makes that ironic statement of yours about the speed of sound-waves quite peculiar as it is mathematically and logically unrelated to what I wrote)
Going down into the complexity of the actual process, whilst interesting, isn't going to answer the OPs question in an accessible and reasonably short manner using language that most people can understand.
LOL!
Reduced to name calling.
Good try, shame you don't have the chops (as the way you express yourself gave away very early on)
I don't know why you are pretending to have physics knowledge when you very obviously do not have an education in it. What do you get out of pretending to be an expert on the internet? There's no reward for it.
Thank you for this. Everything above it was just people saying the stick would move slower than light, nothing about why!