Leading-order calculation of electric conductivity in hot quantum electrodynamics from diagrammatic methods

Journal Article · Mon Jan 15 04:00:00 EST 2007 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.75.025014· OSTI ID:21010927

Gagnon, Jean-Sebastien; Jeon, Sangyong ^[1]

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1. Physics Department, McGill University, 3600 University street, Montreal, H3A 2T8 (Canada)

Using diagrammatic methods, we show how the Ward identity can be used to constrain the ladder kernel in transport coefficient calculations. More specifically, we use the Ward identity to determine the necessary diagrams that must be resummed using an integral equation. One of our main results is an equation relating the kernel of the integral equation with functional derivatives of the full self-energy; it is similar to what is obtained with two-particle irreducible (2PI) effective action methods. However, since we use the Ward identity as our starting point, gauge invariance is preserved. Using power counting arguments, we also show which self-energies must be included in the resummation at leading order, including 2 to 2 scatterings and 1 to 2 collinear scatterings with the Landau-Pomeranchuk-Migdal effect. We show that our quantum field theory result is equivalent to the one of Arnold, Moore, and Yaffe obtained using effective kinetic theory. In this paper we restrict our discussion to electrical conductivity in hot QED, but our method can in principle be generalized to other transport coefficients and other theories.

• OSTI ID: 21010927
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 2 Vol. 75; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACTION INTEGRAL
CALCULATION METHODS
ELECTRIC CONDUCTIVITY
FEYNMAN DIAGRAM
GAUGE INVARIANCE
INTEGRAL EQUATIONS
QUANTUM ELECTRODYNAMICS
SELF-ENERGY
WARD IDENTITY