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Convergence of Perturbation Expansions in Fermionic Models. Part 2: Overlapping Loops

Joel Feldman·Horst Knoerrer·Eugene Trubowitz
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Abstract

We improve on the abstract estimate obtained in Part 1 by assuming that there are constraints imposed by `overlapping momentum loops'. These constraints are active in a two dimensional, weakly coupled fermion gas with a strictly convex Fermi curve. The improved estimate is used in another paper to control everything but the sum of all ladder contributions to the thermodynamic Green's functions.

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Joel Feldman, Horst Knoerrer, Eugene Trubowitz. 2002-09-21. Convergence of Perturbation Expansions in Fermionic Models. Part 2: Overlapping Loops. https://arxiv.org/abs/math-ph/0209046

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