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Comment by amelius | Hacker News Reader

Meanwhile there are quarks inside every regular atom moving at speeds like 0.99995c ...

If the spatial extent of the proton is not infinite, this would imply that the charged quarks making up the proton are accelerating. Why aren't these quarks then emitting electromagnetic radiation, thus slowing down? I thought electrons were essentially standing waves around the nucleus, and thus not accelerating. Maybe there is a good youtube video explainer? Seems like there would also be an associated temperature and blackbody radiation of these quarks.

Quarks don't have quantum energy states to transition between, hence they aren't subject to radiating photons due to acceleration.

Similar to why the electron in a hydrogen atom doesn't keep emitting radiation and crash into the nucleus once it reaches its ground state... there's no lower state for it to jump to.

Electrons in an antenna aren't transitioning between quantum states and are still radiating.

That's a good point, I don't know what's up with that. Google just says, "A single oscillating electron does not continuously emit radio waves; it has a microscopic probability of emitting a single RF photon during a given cycle." It would be necessary to delve into the whole QED thing to get a better explanation, based on what I'm reading.

Either way, quarks don't have an electron-like magnetic moment, so they aren't capable of coupling to the EM field.

Yes they are. They are transitioning through levels in the conduction band where you have plenty of them.

Every time you see a macroscopic phenomena, you are looking at a stupidly high amount of quantum levels with very similar energies.

because conservation of energy dominates

"The laws that bind an ox do not bind Jupiter" applies to quantum particles.

Interesting -- does that have any macroscopic/real world impact?

well, 90%+ of the mass of a proton comes from moving stuff, rather than rest mass of the quarks.

so the real world impact is, having anything at all

And this mass is again an emergent property of Einstein's relativity ...

I think I recently learned that the Higgs is actually not that much part of imparting mass for atomic particles. I thought it imparted all mass.

just enough to keep electrons from staying at light speed like photons

> I thought it imparted all mass.

It’s all relative; in the quarks frame of reference it does get all its mass from the interaction with the Higgs field.

I really want to read more about this. It’s fascinating but also very difficult to wrap your head around. I did enjoy the Feynman talks.

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