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Variational perturbation expansion for strong-coupling coefficients of the anharmonic oscillator

W. Janke·H. Kleinert
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Abstract

As an application of a recently developed variational perturbation theory we find the first 22 terms of the convergent strong-coupling series expansion for the ground state energy of the quartic anharmonic oscillator.

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W. Janke, H. Kleinert. 1995-02-19. Variational perturbation expansion for strong-coupling coefficients of the anharmonic oscillator. https://doi.org/10.1103/physrevlett.75.2787

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