Abstract:
We study isolated quotient singularities by finite group
schemes in positive characteristic. We compute invariants, study the
uniqueness of the quotient presentation, and compute some
deformation spaces. A special emphasis is laid on the dichotomy
between quotient singularities by linearly reductive group schemes
and by group schemes that are not linearly reductive. We essentially
classify the linearly reductive ones, give applications, and make
some conjectures. This is joint work with Gebhard Martin (Bonn) and
Yuya Matsumoto (Tokyo).
