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Resummation of perturbation series and reducibility for Bryuno skew-product flows

Guido Gentile
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Abstract

We consider skew-product systems on T^d x SL(2,R) for Bryuno base flows close to constant coefficients, depending on a parameter, in any dimension d, and we prove reducibility for a large measure set of values of the parameter. The proof is based on a resummation procedure of the formal power series for the conjugation, and uses techniques of renormalisation group in quantum field theory.

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Guido Gentile. 2005-12-01. Resummation of perturbation series and reducibility for Bryuno skew-product flows. https://doi.org/10.1007/s10955-006-9127-6

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