Quantum Kinetic Theory for Quantum Chromodynamics
Abstract
We develop a quantum kinetic theory for QCD, which incorporates all leading order collision terms. At lowest order in gradient expansion, it reproduces the spin-averaged Boltzmann equation with both elastic and inelastic collisions. At next order in gradient expansion, the solution to the quantum kinetic equations give spin polarization of on-shell quarks and gluons in quark-gluon plasma when the gradients are of hydrodynamic ones. A power counting in the coupling shows the spin polarization behaves differently in vortical and non-vortical gradients: the former is free of collisional contribution to leading order, while the latter contains a collisional contribution at parametrically the same order as the free theory counterpart. We also find the inelastic collision in a spin basis provides a possible mechanism for conversion between spin and orbital angular momentum.
Keywords
Cite
@article{arxiv.2603.04263,
title = {Quantum Kinetic Theory for Quantum Chromodynamics},
author = {Shu Lin},
journal= {arXiv preprint arXiv:2603.04263},
year = {2026}
}
Comments
44 pages, 18 figures