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arXiv · 2005.08933

Correlation Energy of a Weakly Interacting Fermi Gas

Niels Benedikter·Phan Thành Nam·Marcello Porta·Benjamin Schlein·Robert Seiringer
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Abstract

We derive rigorously the leading order of the correlation energy of a Fermi gas in a scaling regime of high density and weak interaction. The result verifies the prediction of the random-phase approximation. Our proof refines the method of collective bosonization in three dimensions. We approximately diagonalize an effective Hamiltonian describing approximately bosonic collective excitations around the Hartree-Fock state, while showing that gapless and non-collective excitations have only a negligible effect on the ground state energy.

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Niels Benedikter, Phan Thành Nam, Marcello Porta, Benjamin Schlein, Robert Seiringer. 2020-05-18. Correlation Energy of a Weakly Interacting Fermi Gas. https://doi.org/10.1007/s00222-021-01041-5

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