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arXiv · 1011.4685

Extensions panach\'ees autoduales

Daniel Bertrand
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Abstract

We study self-duality of Grothendieck's blended extensions (extensions panach\'ees) in the context of a tannakian category. The set of equivalence classes of symmetric, resp. antisymmetric, blended extensions is naturally endowed with a torsor structure, which enables us to compute the unipotent radical of the associated monodromy groups in various situations

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Daniel Bertrand. 2010-11-21. Extensions panach\'ees autoduales. https://arxiv.org/abs/1011.4685

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