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Correlation induced collapse of many-body systems with zero-range potentials

D. V. Fedorov·A. S. Jensen
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Abstract

The zero-range potential is customarily employed in various mean-field calculations of many-body systems in atomic and nuclear physics within, correspondingly, Gross-Pitaevskii and Skyrme-Hartree-Fock approach. We argue, however, that a many-body system with zero-range potentials is unstable against clusterization into collapsed three-body subsystems. We show that neither the density dependence of the potential nor an additional repulsive three-body potential can prevent this unexpected correlational collapse if the potentials are of zero range. Therefore the zero-range potential can only be used in many-body calculations where all three-body correlations are explicitly excluded.

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D. V. Fedorov, A. S. Jensen. 2001-02-20. Correlation induced collapse of many-body systems with zero-range potentials. https://doi.org/10.1103/physreva.63.063608

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