paper

Continuity of the radius of convergence of differential equations on -adic analytic curves

arXiv:0809.2479

Abstract

This paper deals with connections on -adic analytic curves, in the sense of Berkovich. The curves must be compact but the connections are allowed to have a finite number of meromorphic singularities on them. For any choice of a semistable formal model of the curve, we define an intrinsic notion of normalized radius of convergence as a function on the curve, with values in . For a sufficiently refined choice of the semistable model, we prove continuity and logarithmic concavity of that function. We characterize \emph{Robba connections}, that is connections whose sheaf of solutions is constant on any open disk contained in the curve.

51 pages, 4 figures

References in corpus (2)