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An inversion theorem in Fermi surface theory

J. Feldman·M. Salmhofer·E. Trubowitz
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Abstract

We prove a perturbative inversion theorem for the map between the interacting and the noninteracting Fermi surface for a class of many fermion systems with strictly convex Fermi surfaces and short-range interactions between the fermions. This theorem gives a physical meaning to the counterterm function K that we use in the renormalization of these models: K can be identified as that part of the self--energy that causes the deformation of the Fermi surface when the interaction is turned on.

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J. Feldman, M. Salmhofer, E. Trubowitz. 2000-01-20. An inversion theorem in Fermi surface theory. https://arxiv.org/abs/math-ph/0001031

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