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Title: Bosonic effective action for interacting fermions

Abstract

We compare different versions of a bosonic description for systems of interacting fermions, with particular emphasis on the free-energy functional. The bosonic effective action makes the issue of symmetries particularly transparent. A systematic expansion for the bosonic effective action starts with a solution to the lowest-order Schwinger-Dyson or gap equation. We propose a two-particle irreducible formulation of an exact functional renormalization group equation for computations beyond leading order. On this basis we suggest a renormalized gap equation. This approach is compared with functional renormalization in a partially bosonized setting.

Authors:
 [1]
  1. Institut fuer Theoretische Physik, Philosophenweg 16, 69120 Heidelberg (Germany)
Publication Date:
OSTI Identifier:
20976708
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevB.75.085102; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACTION INTEGRAL; CALCULATION METHODS; COMPARATIVE EVALUATIONS; EQUATIONS; FERMIONS; FREE ENERGY; PARTICLES; RENORMALIZATION; SYMMETRY

Citation Formats

Wetterich, C. Bosonic effective action for interacting fermions. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.085102.
Wetterich, C. Bosonic effective action for interacting fermions. United States. doi:10.1103/PHYSREVB.75.085102.
Wetterich, C. Thu . "Bosonic effective action for interacting fermions". United States. doi:10.1103/PHYSREVB.75.085102.
@article{osti_20976708,
title = {Bosonic effective action for interacting fermions},
author = {Wetterich, C.},
abstractNote = {We compare different versions of a bosonic description for systems of interacting fermions, with particular emphasis on the free-energy functional. The bosonic effective action makes the issue of symmetries particularly transparent. A systematic expansion for the bosonic effective action starts with a solution to the lowest-order Schwinger-Dyson or gap equation. We propose a two-particle irreducible formulation of an exact functional renormalization group equation for computations beyond leading order. On this basis we suggest a renormalized gap equation. This approach is compared with functional renormalization in a partially bosonized setting.},
doi = {10.1103/PHYSREVB.75.085102},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 8,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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