English

Particle number in kinetic theory

High Energy Physics - Theory 2009-11-07 v2 Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology Quantum Physics

Abstract

We provide a derivation for the particle number densities on phase space for scalar and fermionic fields in terms of Wigner functions. Our expressions satisfy the desired properties: for bosons the particle number is positive, for fermions it lies in the interval between zero and one, and both are consistent with thermal field theory. As applications we consider the Bunch-Davies vacuum and fermionic preheating after inflation.

Keywords

Cite

@article{arxiv.hep-th/0211219,
  title  = {Particle number in kinetic theory},
  author = {Bjorn Garbrecht and Tomislav Prokopec and Michael G. Schmidt},
  journal= {arXiv preprint arXiv:hep-th/0211219},
  year   = {2009}
}

Comments

9 pages, 2 figures, macros: revtex, epsfig. Published version

R2 v1 2026-07-22T15:14:19.848Z