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Variational Perturbation Theory for the Ground-State Wave Function

Axel Pelster·Florian Weissbach
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Abstract

We evaluate perturbatively the density matrix in the low-temperature limit and thus the ground-state wave function of the anharmonic oscillator up to second order in the coupling constant. We then employ Kleinert's variational perturbation theory to determine the ground-state wave function for all coupling strengths.

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Axel Pelster, Florian Weissbach. 2001-05-20. Variational Perturbation Theory for the Ground-State Wave Function. https://doi.org/10.1142/9789812811240_0028

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