Open questions for strongly interacting Fermi gases with zero-range interactions
Abstract
We review some unresolved theoretical issues in three-dimensional two-component Fermi gases, drawing on recent experiments on cold atoms in immaterial traps close to a magnetic Feshbach resonance. We distinguish successively (i) the open questions arising in the few-body problem with Wigner-Bethe-Peierls contact interactions - essentially the stability of the gas with respect to the Efimov effect and the calculation of the cluster (or virial) coefficients, (ii) those arising in the effective low-energy theory of Landau and Khalatnikov quantum hydrodynamics - essentially the damping of phonon modes and the coherence time of the condensate of pairs, and finally (iii) questions requiring a complete, microscopic solution of the many-body problem, such as the specific properties of the acoustic excitation branch (Goldstone) of the condensate of pairs, or its collective excitation branch (Higgs) in the broken-pair continuum.
Cite
@article{arxiv.2410.20866,
title = {Open questions for strongly interacting Fermi gases with zero-range interactions},
author = {Yvan Castin},
journal= {arXiv preprint arXiv:2410.20866},
year = {2025}
}
Comments
70 pages, contribution to the Proceedings of the 2024 IHP symposium ''Open questions in the quantum many-body problem'', in French and in English