Extensions and torsors for finite group schemes
نویسندگان
چکیده
We give an explicit description of the category central extensions a group scheme by sheaf Abelian groups. Based on this, we describe framework for computing with finite locally free commutative schemes, torsors under such schemes and groups isomorphism classes these objects.
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ژورنال
عنوان ژورنال: Expositiones Mathematicae
سال: 2023
ISSN: ['1878-0792', '0723-0869']
DOI: https://doi.org/10.1016/j.exmath.2023.02.004