Large-D Expansion from Variational Perturbation Theory

Sebastian F. Brandt; Axel Pelster

doi:10.1063/1.2116247

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Large-D Expansion from Variational Perturbation Theory

Sebastian F. Brandt·Axel Pelster

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Abstract

We derive recursively the perturbation series for the ground-state energy of the D-dimensional anharmonic oscillator and resum it using variational perturbation theory (VPT). From the exponentially fast converging approximants, we extract the coefficients of the large-D expansion to higher orders. The calculation effort is much smaller than in the standard field-theoretic approach based on the Hubbard-Stratonovich transformation.

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Sebastian F. Brandt, Axel Pelster. 2005-04-20. Large-D Expansion from Variational Perturbation Theory. https://doi.org/10.1063/1.2116247

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