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arXiv · 0903.2197

Hardy type derivations on generalized series fields

Salma Kuhlmann·Mickael Matusinski
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Abstract

We consider the valued field $\mathds{K}:=\mathbb{R}((Γ))$ of generalized series (with real coefficients and monomials in a totally ordered multiplicative group $Γ$). We investigate how to endow $\mathds{K}$ with a series derivation, that is a derivation that satisfies some natural properties such as commuting with infinite sums (strong linearity) and (an infinite version of) Leibniz rule. We characterize when such a derivation is of Hardy type, that is, when it behaves like differentiation of germs of real valued functions in a Hardy field. We provide a necessary and sufficent condition for a series derivation of Hardy type to be surjective.

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Salma Kuhlmann, Mickael Matusinski. 2012-02-26. Hardy type derivations on generalized series fields. https://doi.org/10.1016/j.jalgebra.2011.11.024

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