4 papers · 1 filter
A generalization of the Hasse-Arf theorem
Ioannis Tsouknidas
We use the theory of Harbater-Katz-Gabber curves to derive a generalization of the Hasse-Arf theorem for complete local field extensions in positive characteristic.
A generating set for the canonical ideal of HKG-curves
Aristides Kontogeorgis, Ioannis Tsouknidas
The canonical ideal for Harbater Katz Gabber covers satisfying the conditions of Petri's theorem is studied and an explicit non-singular model of the above curves is given.
Automorphisms and the canonical ideal
Aristides Kontogeorgis, Alexios Terezakis, Ioannis Tsouknidas
The automorphism group of a curve is studied from the viewpoint of the canonical embedding and Petri's theorem. A criterion for identifying the automorphism group as an algebraic s…
A cohomological treatise of HKG-covers with applications to the Nottingham group
Aristides Kontogeorgis, Ioannis Tsouknidas
We characterize Harbater-Katz-Gabber curves in terms of a family of cohomology classes satisfying a compatibility condition. Our construction is applied to the description of finit…