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arXiv · 1907.05362

Continuous changes of variables and the Magnus expansion

Fernando Casas·Philippe Chartier·Ander Murua
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Abstract

In this paper, we are concerned with a formulation of Magnus and Floquet-Magnus expansions for general nonlinear differential equations. To this aim, we introduce suitable continuous variable transformations generated by operators. As an application of the simple formulas so-obtained, we explicitly compute the first terms of the Floquet-Magnus expansion for the Van der Pol oscillator and the nonlinear Schr\"odinger equation on the torus.

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Fernando Casas, Philippe Chartier, Ander Murua. 2019-07-11. Continuous changes of variables and the Magnus expansion. https://doi.org/10.1088/2399-6528/ab42c1

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