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Quantum Averaging I: Poincaré--von Zeipel is Rayleigh--Schrödinger

Wolfgang Scherer
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Abstract

An exact analogue of the method of averaging in classical mechanics is constructed for self--adjoint operators. It is shown to be completely equivalent to the usual Rayleigh--Schrödinger perturbation theory but gives the sums over intermediate states in closed form expressions. The anharmonic oscillator and the Henon--Heiles system are treated as examples to illustrate the quantum averaging method.

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Wolfgang Scherer. 1994-12-30. Quantum Averaging I: Poincaré--von Zeipel is Rayleigh--Schrödinger. https://doi.org/10.1088/0305-4470%2F27%2F24%2F028

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