8 citations · 35 across the 20 of their papers we have counts for
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math.AG2019
The Deligne-Illusie Theorem and exceptional Enriques surfaces
Stefan Schröer
Building on the results of Deligne and Illusie on liftings to truncated Witt vectors, we give a criterion for non-liftability that involves only the dimension of certain cohomology…
math.AG2019★ 1 cited
The maximal unipotent finite quotient, unusual torsion in Fano threefolds, and exceptional Enriques surfaces
Andrea Fanelli, Stefan Schröer
We introduce and study the maximal unipotent finite quotient for algebraic group schemes in positive characteristics. Applied to Picard schemes, this quotient encodes unusual torsi…
math.AG2019
Moderately ramified actions in positive characteristic
Dino Lorenzini, Stefan Schröer
In characteristic two and dimension two, wild Z/2Z-actions on k[[u,v]] ramified precisely at the origin were classified by Artin, who showed in particular that they induce hypersur…