Convergence Behavior of Variational Perturbation Expansions

1996/09/28 by Janke, Wolfhard, Kleinert, Hagen
#FOS: Physical sciences #Quantum Physics (quant-ph)

paper · doi:10.48550/arxiv.quant-ph/9609027

Abstract

Variational weak-coupling perturbation theory yields converging approximations, uniformly in the coupling strength. This allows us to calculate directly the coefficients of `strong-coupling' expansions. For the anharmonic oscillator we explain the physical origin of the empirically observed convergence behavior which is exponentially fast with superimposed oscillations.

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