On the number of connected components of the ramification locus of a morphism of Berkovich curves

Abstract

Let $k$ be a complete, nontrivially valued non-archimedean field. Given a finite morphism of quasi-smooth $k$-analytic curves that admit finite triangulations, we provide upper bounds for the number of connected components of the ramification locus in terms of topological invariants of the source curve such as its topological genus, the number of points in the boundary and the number of open ends.

arXiv comment20 pages, 3 figures; Final version, Accepted in Mathematische Annalen