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General energy bounds for systems of bosons with soft cores

Richard L. Hall
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Abstract

We study a bound system of N identical bosons interacting by model pair potentials of the form V(r) = A sgn(p)r^p + B/r^2, A > 0, B >= 0. By using a variational trial function and the `equivalent 2-body method', we find explicit upper and lower bound formulas for the N-particle ground-state energy in arbitrary spatial dimensions d > 2 for the two cases p = 2 and p = -1. It is demonstrated that the upper bound can be systematically improved with the aid of a special large-N limit in collective field theory.

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Richard L. Hall. 2000-08-14. General energy bounds for systems of bosons with soft cores. https://doi.org/10.1103/physreva.62.052510

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