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Variational perturbation approach to the Coulomb electron gas

Sang Koo You·Noboru Fukushima
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Abstract

The efficiency of the variational perturbation theory [Phys. Rev. C {\bf 62}, 045503 (2000)] formulated recently for many-particle systems is examined by calculating the ground state correlation energy of the 3D electron gas with the Coulomb interaction. The perturbation beyond a variational result can be carried out systematically by the modified Wick's theorem which defines a contraction rule about the renormalized perturbation. Utilizing the theorem, variational ring diagrams of the electron gas are summed up. As a result, the correlation energy is found to be much closer to the result of the Green's function Monte Carlo calculation than that of the conventional ring approximation is.

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Sang Koo You, Noboru Fukushima. 2002-04-12. Variational perturbation approach to the Coulomb electron gas. https://doi.org/10.1088/0305-4470%2F36%2F37%2F304

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