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quark (Rev #9, changes) in nLab

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Context

Fields and quanta

fields and particles in particle physics

and in the standard model of particle physics:

force field gauge bosons

photon - electromagnetic field (abelian Yang-Mills field)
W, Z, B-boson - electroweak field (Yang-Mills field)
gluon - strong nuclear force (Yang-Mills field)
graviton - field of gravity
infraparticle

scalar bosons

Higgs boson, inflaton (scalar field)

matter field fermions (spinors, Dirac fields)

flavors of fundamental fermions in the standard model of particle physics:
generation of fermions	1st generation	2nd generation	3d generation
quarks (qq)
up-type	up quark (uu)	charm quark (cc)	top quark (tt)
down-type	down quark (dd)	strange quark (ss)	bottom quark (bb)
leptons
charged	electron	muon	tauon
neutral	electron neutrino	muon neutrino	tau neutrino

bound states:
mesons	light mesons: pion (udu d) ρ-meson (udu d) ω-meson (udu d) f1-meson a1-meson	strange-mesons: ϕ-meson (ss¯s \bar s), kaon, K-meson (usu s, dsd s) eta-meson (uu+dd+ssu u + d d + s s) charmed heavy mesons*: D-meson (uc u c, dcd c, scs c) J/ψ-meson (cc¯c \bar c)	bottom heavy mesons: B-meson (qbq b) ϒ-meson (bb¯b \bar b)
baryons	nucleons: proton (uud)(u u d) neutron (udd)(u d d)

(also: antiparticles)

effective particles

Goldstone bosons

hadrons (bound states of the above quarks)

meson
- scalar meson
  - σ-meson
  - pion
  - kaon
  - D-meson
  - B-meson
- vector meson
  - ω-meson
  - ρ-meson
  - f1-meson
  - a1-meson
  - b1-meson
  - h1-meson
  - K*-meson
- tensor meson
- quarkonium
  - charmonium
  - ϒ-meson
exotic meson
- XYZ meson
- tetraquark
baryon
- nucleon
  - proton
  - neutron
  - chemical element
    - carbon
    - nitrogen
- Lambda baryon
- pentaquark

solitons

in grand unified theory

minimally extended supersymmetric standard model

superpartners

bosinos:

gravitino - field of supergravity (Rarita-Schwinger field)
gaugino - super Yang-Mills field
gluino

sfermions:

squark

dark matter candidates

WIMP
axion

Exotica

auxiliary fields

Idea

The Quarksquarkss are one of the fundamental particles/matter fields in the standard model of particle physics. Quarks couple to the Yang-Mills theory given by QCD.

At room-temperature quarks always form bound states to hadrons. This phenomenon of confinement is quantitatively well-reproduced by lattice QCD computations (see Fodor-Hoelbling 12) and qualitatively well reproduced by conceptual arguments such as the AdS/QCD correspondence, but a full analytic proof of confinement from a rigorous AQFT-like foundation of QCD remains open, see the mass gap problem.

However, at high temperature QCD goes through a deconfinement phase transition and enters another phase of matter known as the quark-gluon plasma. As the name suggests, here quarks and gluons are free.

References

Ab-initio lattice computation

Due to confinement, before the quark-gluon plasma was seen in experiment it was a logical possibility that the quark-model of QCD is not actually correct. But more recend ab-initio computation in lattice QCD show that starting with the quark model, at least the light hadron bound states observes in experiment are reproduced by these ab-initio computations. This is discussed in the following references, see the good review Fodor-Hoelbling 12

S. Durr, Z. Fodor, J. Frison, C. Hoelbling, R. Hoffmann, S.D. Katz, S. Krieg, T. Kurth, L. Lellouch, T. Lippert, K.K. Szabo, G. Vulvert,

Ab-initio Determination of Light Hadron Masses,

Science 322:1224-1227,2008 (arXiv:0906.3599)
Zoltan Fodor, Christian Hoelbling, Light Hadron Masses from Lattice QCD, Rev. Mod. Phys. 84, 449, (arXiv:1203.4789)
S. Aoki et. al. Review of lattice results concerning low-energy particle physics (arXiv:1607.00299)