An introduction to the quark model

Few-charge systems History of the quark model Mesons Baryons Multiquarks and other exotics Outlook
The origin of spin dependent forces
Much discussed at the beginning of charmonium
Then discussed by Lattice QCD (Rebbi et al., etc.)
And other non perturbative methods (Brambilla et al.)
Early approaches inspired by
QED
One-boson-exchange picture of nuclear forces
Scalar exchange → central, and spin-orbit,
Vector exchange → central, spin-spin, tensor and spin-orbit
Early models: vector linked to 1/r and scalar linked to
confinement,
One should be careful: some terms come from the reduction of
Dirac operators in terms of Pauli spinors, other come from the
non-relativistic reduction (Thomas precession)
It took some time to get a consistent picture compatible with
Lorentz invariance (Gromes, Eichten-Sucher, etc.)
JMR Quark Model