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[MadMojoMonkey]

Out of interest do you not think it's strange that all protons are the same, all electrons etc etc. Is there literally 0 scope for them to be different? Or could there still room for their to be tiny differences between them that we just aren't currently aware of?

I don't think it's strange now... I can't remember if I thought it was strange the first time I heard it.


The next paragraph talks about color in a completely non-intuitive sense. Particles are too small to have a color, as you and I experience color. Physicists notices this obscure quality in quarks and didn't know how to talk about it, so they used color, which is handy for a couple of reasons I wont get into. The bottom line is that this is "quantum color" and not visual color.

Protons are weird... I don't want to talk about their same-ness, because I'm not trained in Quantum chromodynamics. They ARE the same, but they are also always in a state of flux, due to the quarks exchanging color when they express forces on each other. There is always 1 green quark, 1 red quark, and 1 blue quark, but since the Proton is made of 2 Up quarks and 1 Down Quark, it is not necessarily the case for 2 'identical' protons that their Down quark is the same color.


There is always the possibility that any scientific statement is wrong. Science isn't concerned with 'truth' so much as 'observable predictability'. There is always room for new information to alter current statements.

There’s no a priori reason that fundamental particles have to be fundamental. We don’t know for certain that electrons (or any particles) are fundamental.

Quantum Electrodynamics (the most precise theory ever measured) says an electron-like particle (i.e. a particle of spin-1/2) is fundamental. Half-spin particles are the fundamental excitations of the field, according to Quantum Electrodynamics.

And do we ever find more exotic particles taking the same roll in a larger atom even if just for a brief period of time? I'm pretty sure I remember that you can add muons to certain things in place of electrons but this is all ages ago and it was never very deeply discussed.

Absolutely, but they are unstable.

You (well someone) can replace the electron in Hydrogen with a Muon, since they have identical charge. However, the Muon is less stable than an electron (which is fundamental and therefore completely stable), and will eventually decay into other particles. This ionizes the Hydrogen atom, leaving only its nucleus, which is just a proton.

Anti-Hydrogen atoms have been made, which consist of an anti-proton and a positron. These are as stable as a 'regular' Hydrogen, but still difficult to maintain. Since the positron will annihilate with any electron it encounters, it is difficult to contain it.

You can wiki "Exotic Atoms" for some more descriptions.

[Pelion]

However, the Muon is less stable than an electron (which is fundamental and therefore completely stable)...

But Muons are also fundamental particles (and electrons are not always completely stable)

[MadMojoMonkey]

But Muons are also fundamental particles (and electrons are not always completely stable)

Excellent catch, what a screw-up on my part.

... working on where I got that notion, and what the best description is...

EDIT: I had it in my head that a Muon was a Meson, or 2-quark structure. It was once called a Mu meson, but later found to be a lepton. So that's why I thought it was unstable... but even that much is a brain fart, apparently. It is true that Muons and Tauons are both fundamental particles and unstable.

They are called fundamental particles because when their structure is probed, it shows no internal pieces. It can still decay because QM is tricky as anything and so long as conservation laws are maintained, anything can change into anything else.