Soft Modes, Quantum Transport and Kinetic Entropy

Yu. B. Ivanov, J. Knoll, H. Van Hees, D. N. Voskresensky

Submitted on 31 January 2000


The effects of the propagation of particles which have a finite life-time and an according width in their mass spectrum are discussed in the context of transport descriptions. In the first part the coupling of soft photon modes to a source of charged particles is studied in a classical model which can be solved completely in analytical terms. The solution corresponds to a re-summation of certain field theory diagrams. The general properties of broad resonances in dense finite temperature systems are discussed at the example of the ρ-meson in hadronic matter. The second part addresses the problem of transport descriptions which also account for the damping width of the particles. The Kadanoff--Baym equation after gradient approximation together with the Φ-derivable method of Baym provides a self-consistent and conserving scheme. Memory effects appearing in collision term diagrams of higher order are discussed. We derive a generalized expression for the nonequilibrium kinetic entropy flow, which includes corrections from fluctuations and mass-width effects. In special cases an H-theorem is proved. Memory effects in collision terms provide contributions to the kinetic entropy flow that in the Fermi-liquid case recover the famous bosonic type T3lnT correction to the specific heat of liquid Helium-3.


Comment: Contribution to Proc. of Int. Workshop "Kadanoff-Baym Equations - Progress and Perspectives for Many-Body Physics" Rostock (Germany), September 20-24 1999, ed. M.Bonitz, World Scientific (2000)

Subjects: Nuclear Theory; Astrophysics; High Energy Physics - Phenomenology; Quantum Physics