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arXiv · 1501.02992

q-Deformation of Meromorphic Solutions of Linear Differential Equations

Thomas Dreyfus
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Abstract

In this paper, we consider the behaviour, when $q$ goes to $1$, of the set of a convenient basis of meromorphic solutions of a family of linear $q$-difference equations. In particular, we show that, under convenient assumptions, such basis of meromorphic solutions converges, when $q$ goes to $1$, to a basis of meromorphic solutions of a linear differential equation. We also explain that given a linear differential equation of order at least two, which has a Newton polygon that has only slopes of multiplicities one, and a basis of meromorphic solutions, we may build a family of linear $q$-difference equations that discretizes the linear differential equation, such that a convenient family of basis of meromorphic solutions is a $q$-deformation of the given basis of meromorphic solutions of the linear differential equation.

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Thomas Dreyfus. 2015-07-13. q-Deformation of Meromorphic Solutions of Linear Differential Equations. https://doi.org/10.1016/j.jde.2015.07.010

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