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arXiv · 0812.3604

Density Matrix Functional Theory for the Lipkin model

Denis Lacroix
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Abstract

A Density Matrix Functional theory is constructed semi-empirically for the two-level Lipkin model. This theory, based on natural orbitals and occupation numbers, is shown to provide a good description for the ground state energy of the system as the two-body interaction and particle number vary. The application of Density Matrix Functional theory to the Lipkin model illustrates that it could be a valuable tool for systems presenting a shape phase-transition such as nuclei. The improvement of one-body observables description as well as the interest for Energy Density Functional theory are discussed.

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Denis Lacroix. 2008-12-18. Density Matrix Functional Theory for the Lipkin model. https://doi.org/10.1103/physrevc.79.014301

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