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arXiv · 1204.6532

Off-diagonal kinetic theory in ultrasoft momentum region at high temperature

Daisuke Satow·Yoshimasa Hidaka
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Abstract

We derive a linearized kinetic equation for fermionic excitations with an ultrasoft momentum, g^2T, from the Kadanoff-Baym equation in a Yukawa model and quantum electrodynamics (QED) at extremely high T, where g is the coupling constant. We show that this equation is equivalent to the self-consistent equation in the resummed perturbation theory used in the analysis of the fermion spectrum with the ultrasoft momentum. Furthermore, we derive the equation that determines the n-point function with external lines for a pair of fermions and (n-2) bosons with ultrasoft momenta in QED.

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Daisuke Satow, Yoshimasa Hidaka. 2012-04-30. Off-diagonal kinetic theory in ultrasoft momentum region at high temperature. https://doi.org/10.1103/physrevd.85.116009

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