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Remarks on the method of comparison equations (generalized WKB method) and the generalized Ermakov-Pinney equation

A Kamenshchik·M Luzzi·G Venturi
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Abstract

The connection between the method of comparison equations (generalized WKB method) and the Ermakov-Pinney equation is established. A perturbative scheme of solution of the generalized Ermakov-Pinney equation is developed and is applied to the construction of perturbative series for second-order differential equations with and without turning points.

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A Kamenshchik, M Luzzi, G Venturi. 2006-02-09. Remarks on the method of comparison equations (generalized WKB method) and the generalized Ermakov-Pinney equation. https://doi.org/10.1007/s11182-010-9375-4

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