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arXiv · math/0605716

About the Trimmed and the Poincare-Dulac normal form of diffeomorphisms

Abstract

We study two particular continuous prenormal forms as defined by Jean Ecalle and Bruno Vallet for local analytic diffeomorphism: the Trimmed form and the Poincare-Dulac normal form. We first give a self-contain introduction to the mould formalism of Jean Ecalle. We provide a dictionary between moulds and the classical Lie algebraic formalism using non-commutative formal power series. We then give full proofs and details for results announced by J. Ecalle and B. Vallet about the Trimmed form of diffeomorphisms. We then discuss a mould approach to the classical Poincare-Dulac normal form of diffeomorphisms. We discuss the universal character of moulds taking place in normalization problems.

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Jacky Cresson, Jasmin Raissy. 2006-05-29. About the Trimmed and the Poincare-Dulac normal form of diffeomorphisms. https://arxiv.org/abs/math/0605716

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