MagicalSkyMan t1_j0fatgf wrote on December 16, 2022 at 5:26 AM

Reply to comment by Weed_O_Whirler in Does rotation break relativity? by starfyredragon

So I'm a total noob at physics but I disagree with your claim about acceleration being more measurable than speed.

Being pressed back to your seat is a consequence of the car seat being the source of the force that is making you accelerate while the force is not being distributed to each of the particles (that you are composed of) at the same instant. If the car was transferring that same force (like magnetically or something) to each of your particles uniformly then you wouldn't be noticing the acceleration as there would be no compression happening within your body.

Maybe there is some other effect that happens during acceleration that could be used to determine acceleration is taking place? I'm trying to think in terms of a single electron or neutron or something for simplicity. Not coming up with anything so far.

Otherwise-Way-1176 t1_j0fbpmg wrote on December 16, 2022 at 5:35 AM

There are fictitious forces in non-inertial reference frames: https://en.m.wikipedia.org/wiki/Fictitious_force

It’s easier to think about a rotating reference frame for this. You could observe a centripetal force or the Coriolis force.

Amadex t1_j0fvu4q wrote on December 16, 2022 at 9:53 AM

>If the car was transferring that same force (like magnetically or something) to each of your particles uniformly then you wouldn't be noticing the acceleration as there would be no compression happening within your body.

It's paradoxical because would need an accelerometer to know the intensity of the field that you would need to cancel acceleration (putting aside the fact that it is relatively trivial to measure magnetic fields and therefore distinguish it from acceleration).