nLab preon

Contents

Context

Physics

physics, mathematical physics, philosophy of physics

Surveys, textbooks and lecture notes


theory (physics), model (physics)

experiment, measurement, computable physics

Contents

Idea

While in the standard model of particle physics all hadrons and mesons are bound states of quarks, the quarks themselves, together with the leptons, are assumed to be “elementary” particles, hence not themselves bound states of other particles.

While this does fit very well with current experimental observation, one may speculate if at a higher energy scale quarks and/or leptons are themselves bound states of more fundamental particles. These hypothetical more fundamental particles are then generically called preons.

fields and particles in particle physics

and in the standard model of particle physics:

force field gauge bosons

scalar bosons

matter field fermions (spinors, Dirac fields)

flavors of fundamental fermions in the
standard model of particle physics:
generation of fermions1st generation2nd generation3d generation
quarks (qq)
up-typeup quark (uu)charm quark (cc)top quark (tt)
down-typedown quark (dd)strange quark (ss)bottom quark (bb)
leptons
chargedelectronmuontauon
neutralelectron neutrinomuon neutrinotau neutrino
bound states:
mesonslight 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)
baryonsnucleons:
proton (uud)(u u d)
neutron (udd)(u d d)

(also: antiparticles)

effective particles

hadrons (bound states of the above quarks)

solitons

in grand unified theory

minimally extended supersymmetric standard model

superpartners

bosinos:

sfermions:

dark matter candidates

Exotica

auxiliary fields

References

Textbook account:

See also:

A proposal for an embedding of preon models into string theory is in

  • Noriaki Kitazawa, Dynamical Generation of Yukawa Couplings in Intersecting D-brane Models, JHEP 0411 (2004) 044 (arXiv:hep-th/0409146)

Last revised on August 15, 2021 at 10:29:10. See the history of this page for a list of all contributions to it.