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American Journal of Physics

A Simple Variational Formula in Quantum

David Park

Published Sep 1, 1973• 1 citation
Publisher

Abstract

If one assumes that the change in a ground-state wave function produced by a perturbing potential V is proportional to V, a general and very simple formula for the perturbation in energy results. The formula is illustrated with two examples.
DOI
10.1119/1.1987476

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