Two physics questions.

[Kai]

1. What are quarks composed of? I know that neutrons and protons are composed of up and down quarks, among other things, but I can find no resources about the make up of quarks themselves.

2. What is energy? I mean that, when we come right down to it, we have four basic forces, and all energy is derived from those forces, but what is energy /really/? This is not a "Does 2+2 really really equal 4" question. I believe (IOW, I anticipate) that gravitational energy is the warping of space time by mass, but what is electromagnetic energy, for example? And how is that contained as a quantum field we call a photon?

I'm not really interested in untestable hypotheticals. String "theory" being one of those.

ETA: And if these are really stupid questions, please let me know. My qualifications are but a year of non majors physics in undergrad.

[LMNO]

1. Quarks, for now, seem to be elemental.  They aren't made of anything, they simply are.  Kind of like how we thought atoms were elelmental, before we found out they had parts.  For now, they "are" the building blocks.

2. Short answer: dunno.  Still trying to work that one out.


Longer answers available upon request.

[Doktor Howl]

1. What are quarks composed of?

Muster Mark's coffee grounds.

[Kai]

1. Quarks, for now, seem to be elemental.  They aren't made of anything, they simply are.  Kind of like how we thought atoms were elelmental, before we found out they had parts.  For now, they "are" the building blocks.

2. Short answer: dunno.  Still trying to work that one out.


Longer answers available upon request.

So, are quarks solid, or are they probability fields, like photons?

[Jasper]

Someone once told me they might be energy, but that's speculative as I understand it.

[Kai]

Someone once told me they might be energy, but that's speculative as I understand it.

Which goes back to "what is energy". As I understand it from physics, energy is the ability to do work, and while we order energy in all these different forms (potential, kinetic, heat, light, etc), there are really only 4 basic forms, coming from the four forces. So, what is electromagnetic energy? What is that energy responsible for holding the nucleus together (strong nuclear force) and what in the world is the energy responsible for radioactive decay (weak nuclear force)? If gravitational force is in reality the warping effect of quark and lepton mass (whatever those might actually be) on 4-dimensional space time, then at least that has an answer. Not that I can actually wrap my head around the tesseract like nature of 4 dimensions, but I'm not sure thats possible for humans at the moment.

[Kai]

Or maybe quarks are responsible for strong nuclear forces. Take a set of two up-down-down configurations and pair those with a set of two down-up-up configurations and whoila, a helium nucleus, stable, inert. The most perfect example of strong nuclear "forces". Maybe it's just in the quarks.

[Bebek Sincap Ratatosk]

I think quarks are still a label for X in the model.

[Jasper]

Well, I really have no answers but in attempting to find one I learned some stuff.  

[Igor]

Or maybe quarks are responsible for strong nuclear forces. Take a set of two up-down-down configurations and pair those with a set of two down-up-up configurations and whoila, a helium nucleus, stable, inert. The most perfect example of strong nuclear "forces". Maybe it's just in the quarks.

The strong nuclear force is transmitted by "gluons"
The electromagnetic by photons
The weak nuclear is transmitted by W and Z bosons.
Gravity is, of course, awkward.

Ridiculous analogy: Two people on rollerskates throwing a ball back and forth. They are repelled by exchanging the ball. It's kind of the same for two electrons exchanging (virtual) photons and being repelled.

So you could say energy is made of exchange particles. A photon (or gluon or graviton) is defined as being a "quantum of energy"; the smallest possible amount of energy. Of course, then you ask what's a photon?

[Jasper]

Smells like the teacher's password.

[Kai]

Or maybe quarks are responsible for strong nuclear forces. Take a set of two up-down-down configurations and pair those with a set of two down-up-up configurations and whoila, a helium nucleus, stable, inert. The most perfect example of strong nuclear "forces". Maybe it's just in the quarks.

The strong nuclear force is transmitted by "gluons"
The electromagnetic by photons
The weak nuclear is transmitted by W and Z bosons.
Gravity is, of course, awkward.

Ridiculous analogy: Two people on rollerskates throwing a ball back and forth. They are repelled by exchanging the ball. It's kind of the same for two electrons exchanging (virtual) photons and being repelled.

So you could say energy is made of exchange particles. A photon (or gluon or graviton) is defined as being a "quantum of energy"; the smallest possible amount of energy. Of course, then you ask what's a photon?

I guess I'm trying to figure out where to press Worship.

Gluons haven't been substantiated, AFAIK. They're about as supported as string theory, which is to say, not at all.

W and Z bosons have, but I don't really understand them. Are they just somehow hiding in the nucleus of all atoms, or just radioactive atoms? If so, how the hell do they get in radioactive atoms? Thats a hell of a lot of mass to hide away.

And then theres the matter of photons. Not only the issue of what /is/ a photon really, but why is it that an exchange between two electrons (whatever those might be; not made of quarks) or two protons causes repulsion but the swap between electrons and protons is attractive?

Smells like the teacher's password.

And that's precisely why I don't buy many explanations I read of these things. Most people would answer "why do protons repel each other but electrons and protons attract" with "because protons are positive and electrons are negative" and leave it at that. But positive and negative are just simply names we've put on reality we can't explain. We could say "because protons are strange and electrons are charm" and it would be equally as non-explanatory.

[Jasper]

Which is why I'll bother studying physics when I'm retired.  They'll know more by then.

[Igor]

No, gluons are a verified part of the Standard Model. Which is where I'm taking all this from, and which is why I'm not mentioning gravity.

This list of all the elementary particles might help. The purple are quarks. The green are leptons, ie electron and neutrinos. And the blue are the bosons. Bosons are the exchange particles. They are, in a way, energy.



Currently it doesn't make sense to ask what are these things. At this point, these things just are. Maybe that's a good spot to "worship"?

[Doktor Howl]

1. Quarks, for now, seem to be elemental.  They aren't made of anything, they simply are.  Kind of like how we thought atoms were elelmental, before we found out they had parts.  For now, they "are" the building blocks.

2. Short answer: dunno.  Still trying to work that one out.


Longer answers available upon request.

So, are quarks solid, or are they probability fields, like photons?

Solid.

I keep a jar of them on my desk.  But they're really hard to see if you spill them.