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What particles make up a quark? We all know quarks (3, uud) make up a proton. I read on Wikipedia they are called "hadrons" ,but how do they work?

Is the collection wave functions of the components of the quark representative of the wavefunction of the quark itself?

Qmechanic
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Investor
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    You misunderstood - quarks make up the hadrons like protons and neutrons. We don't know if there's anything making up the quarks, but there's no evidence indicating that they possess substructure. – ACuriousMind Oct 30 '14 at 16:28
  • Related: http://physics.stackexchange.com/q/16048/2451 , http://physics.stackexchange.com/q/141554/2451 and links therein. – Qmechanic Oct 30 '14 at 16:30
  • Ooh, you're right @ACuriousMind... Protons and neutrons are hadrons. – Investor Oct 30 '14 at 16:31
  • elementary particles are point particles by all indications of our experiments and the theoretical models that fit and predict their behavior. http://en.wikipedia.org/wiki/Standard_Model – anna v Oct 30 '14 at 16:33

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You got that the wrong way around. Hadrons are made up of quarks. There are different types of hadrons, e.g. baryons (3 quarks) and mesons (1 quark, 1 antiquark). So a proton is just one special type of baryon and therefore also a hadron.

Now what quarks are made up of is not a sensible question in the frame we use to think about particle physics nowadays. Quarks are the smallest units or building blocks of the Standard Model of particle physics and therefore cannot be split up into further constituents.

On the other hand, if one chooses to believe in string theory, basically everything is made up of tiny vibrating strings, including quarks.

PassfishSwordword
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  • So if If i have understood clearly: quarks are the smallest particles possible and and are fixed points and thus have no possible wavefunction associated to them? But if string theory proves to be true, quarks are made up of tiny vibrating strings? – Investor Oct 30 '14 at 16:40
  • no, pointlike particles definitley can have a wavefunction. Electrons do, for example – Noldig Oct 30 '14 at 16:42
  • Yes, if you will quarks are the smallest particles possible, together with all the other fundamental particles of the SM, that is leptons (e.g. electrons, neutrinos) as well as bosons (e.g. photon, Higgs). They can be described in terms of wavefunctions, just as electrons can. And I guess to say particles "are made up of strings" is a bit sloppy. The correct statement would be that particles are excitations of degrees of freedoms of string theory. If string theory will/can be proven to be true or false is a whole different issue. – PassfishSwordword Oct 30 '14 at 16:44
  • It might be better to say that quarks (and leptons, etc) behave as point-like particles down to the smallest dimension that we can currently measure. That doesn't mean that they are point-like, but it does mean that for all practical purposes today, they can be treated as points. In the future, internal structure may be discovered. The theory that describes that structure might be string theory, but it might be something else. There's no reason to single out string theory in this highly speculative discussion. – garyp Oct 30 '14 at 17:22
  • Is there any particular behaviour associated with pont-like particles? (Classical mechanics or other) – Investor Oct 30 '14 at 19:30
  • See http://en.wikipedia.org/wiki/Point_particle – PassfishSwordword Nov 01 '14 at 15:32