Marco Antei

Extension of finite solvable torsors over a curve

Let R be a complete discrete valuation ring with fraction field K and with algebraically closed residue field of positive characteristic p. Let X be a smooth fibered surface over R. Let G be a finite, étale and solvable K-group scheme and assume that either |G| = pn or G has a normal series of length 2. We prove that for every connected and pointed G-torsor Y over the generic fibre

On the Fundamental Group Scheme of Rationally Chain-Connected Varieties

{X_{\eta}}

Vector bundles over normal varieties trivialized by finite morphisms

of X there exist a regular fibered surface

The fundamental group scheme of a non-reduced scheme

{\widetilde{X}}

Models of torsors over affine spaces

over R and a model map