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arXiv:quant-ph/0105095 · WORLD SCIENTIFIC eBooks

VARIATIONAL PERTURBATION THEORY FOR THE GROUND-STATE WAVE FUNCTION

Axel Pelster, Florian Weissbach

Published Jun 1, 2001• 3 citations
arXivHTMLPDF

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.
DOI
10.1142/9789812811240_0028

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