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A variational approach to the partition function of an interacting many body system

Christian Rummel·Helmut Hofmann
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Abstract

For the calculation of the partition function $\mathcal{Z}$ of small, isolated and interacting many body systems an improvement with respect to previous formulations is presented. By including anharmonicities and employing a variational approach quantum effects can be treated even at very low temperatures. In order to test its accuracy the novel approach is applied to the exactly solvable Lipkin-Meshkov-Glick model (LMGM). For thermodynamic properties and level densities good agreement with the exact calculations is found.

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Christian Rummel, Helmut Hofmann. 2005-03-04. A variational approach to the partition function of an interacting many body system. https://doi.org/10.1016/j.nuclphysa.2005.03.009

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