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arXiv · 1312.4171

On the motive of a commutative algebraic group

Giuseppe Ancona·Stephen Enright-Ward·Annette Huber
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Abstract

We prove a canonical Kunneth decomposition for the motive of a commutative group scheme over a field. Moreover, we show that this decomposition behaves under the group law just as in cohomology. We also deduce applications of the decomposition to the existence of a weight filtration, computation of any Weil cohomology theory and study of 1-motives.

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Giuseppe Ancona, Stephen Enright-Ward, Annette Huber. 2013-12-15. On the motive of a commutative algebraic group. https://arxiv.org/abs/1312.4171

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