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arXiv · 1604.02547

On the group of separable quadratic algebras and stacks

Ilia Pirashvili
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Abstract

The aim of this paper is to study the group of isomorphism classes of torsors of finite flat group schemes of rank 2 over a commutative ring $R$. This, in particular, generalises the group of quadratic algebras (free or projective), which is especially well studied. Our approach however, yields new results even in this case.

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Ilia Pirashvili. 2016-09-18. On the group of separable quadratic algebras and stacks. https://doi.org/10.1017/s0017089518000150

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