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arXiv · 1111.0787

On the energy-momentum spectrum of a homogeneous Fermi gas

Jan Dereziński·Krzysztof A. Meissner·Marcin Napiórkowski
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Abstract

We consider translation invariant quantum systems in thermodynamic limit. We argue that their energy-momentum spectra should have shapes consistent with effective models involving quasiparticles. Our main example is second quantized homogeneous interacting Fermi gas in a large cubic box with periodic boundary conditions, at zero temperature. We expect that its energy-momentum spectrum has a positive energy gap and a positive critical velocity.

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Jan Dereziński, Krzysztof A. Meissner, Marcin Napiórkowski. 2011-11-03. On the energy-momentum spectrum of a homogeneous Fermi gas. https://arxiv.org/abs/1111.0787

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