Boltzmann Collision Term

Abstract

We derive the Boltzmann equation for scalar fields using the Schwinger-Keldysh formalism. The focus lies on the derivation of the collision term. We show that the relevant self-energy diagrams have a factorization property. The collision term assumes the Boltzmann-like form of scattering probability times statistical factors for those self-energy diagrams which correspond to tree level scattering processes. Our proof covers scattering processes with any number of external particles, which come from self-energy diagrams with any number of loops.

17 pages, 4 figures

References in corpus (2)

• Transport equations for chiral fermions to order \hbar and electroweak baryogenesis: Part II
• Transport Theory beyond Binary Collisions

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