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arXiv · 1910.14509

Residues on Affine Grassmannians

Mathieu Florence·Philippe Gille
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Abstract

Given a linear group G over a field k, we define a notion of index and residue of an element g of G(k((t)). This provides an alternative proof of Gabber's theorem stating that G has no subgroups isomorphic to the additive or the commutative group iff G(k[[t]])= G(k((t))). In the case of a reductive group, we offer an explicit connection with the theory of affine grassmannians.

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Mathieu Florence, Philippe Gille. 2019-10-31. Residues on Affine Grassmannians. https://arxiv.org/abs/1910.14509

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