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arXiv · 2311.11945

Bosonized Momentum Distribution of a Fermi Gas via Friedrichs Diagrams

Sascha Lill
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Abstract

Recently, Benedikter and the author proved an approximate formula for the momentum distribution of a 3d fermionic gas interacting by a short-range pair potential in the mean-field regime, within a trial state close to the ground state. Here, we derive an exact formula for the momentum distribution in this trial state, using a diagrammatic formalism due to Friedrichs. We further demonstrate how the formula of Benedikter and the author arises from a restriction of the contributing diagrams to those corresponding to a bosonization approximation.

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BibTeXRIS

Sascha Lill. 2023-11-20. Bosonized Momentum Distribution of a Fermi Gas via Friedrichs Diagrams. https://doi.org/10.1007/978-981-96-3584-9_6

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