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arXiv:2602.12067

Mesoscopic Observables of the Dilute Fermi Gas at Low Energy

Niels Benedikter, Emanuela L. Giacomelli, Asbjørn Bækgaard Lauritsen, Sascha Lill

math-phcond-mat.quant-gasquant-phSubmitted Feb 12, 2026• Announced Feb 13, 2026• 0 citations• Revised Jul 31, 2026 (v2)
v1 · Feb 12, 2026v2 · Jul 31, 2026
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Abstract

We consider a dilute quantum gas of interacting spin-1/2 fermions in the thermodynamic limit. For a trial state that resolves the ground state energy to the precision of the Huang--Yang formula, we compute the expectation values of one-body observables on a mesoscopic scale.
Comments
55 pages, 6 figures

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