Order p automorphisms of p-adic annuli
by
Yannick Henrio
Université Bordeaux I

Let k be an algebraically closed field of characteristic p > 0 and R a discrete valuation ring finite over W(k)[^{p^2}\surd{1}]. We construct order p and p² automorphisms of open annuli over Fr R, and we deduce a theorem concerning liftings of semi-stable curves (Y, G) over k, together with a finite group of automorphisms such that the inertia subgroups are cyclic of order p^an, where a <= 2 and (n, p)=1. We also give a description of the metric geometry of fixed points of order p automorphisms of open annuli with small conductors.

Date received: April 30, 1999