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arXiv · 2009.14170

On the universal extensions in Tannakian categories

Marco D'Addezio·Hélène Esnault
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Abstract

We use the notion of universal extension in a linear abelian category to study extensions of variations of mixed Hodge structure and convergent and overconvergent isocrystals. The results we obtain apply, for example, to prove the exactness of some homotopy sequences for these categories and to study $F$-able isocrystals.

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Marco D'Addezio, Hélène Esnault. 2020-12-06. On the universal extensions in Tannakian categories. https://doi.org/10.1093/imrn%2Frnab107

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