Regularity of the moving Fermi surface: the exact selfenergy

Joel Feldman; Manfred Salmhofer; Eugene Trubowitz

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Regularity of the moving Fermi surface: the exact selfenergy

Joel Feldman·Manfred Salmhofer·Eugene Trubowitz

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Abstract

Regularity of the deformation of the Fermi surface under short-range interactions is established to all orders in perturbation theory. The proofs are based on a new classification of all graphs that are not doubly overlapping. They turn out to be generalized RPA graphs. This provides a simple extension to all orders of the regularity theorem of the Fermi surface movement proven in [FST2]. Models in which the Fermi surface is not symmetric under the reflection p to -p are included.

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Joel Feldman, Manfred Salmhofer, Eugene Trubowitz. 1997-05-27. Regularity of the moving Fermi surface: the exact selfenergy. https://arxiv.org/abs/cond-mat/9705272

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