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arXiv · 1806.11159

A1-invariants in Galois cohomology and a claim of Morel

Tom Bachmann
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Abstract

We establish a variant of the splitting principle of Garibaldi-Merkurjev-Serre for invariants taking values in a strictly homotopy invariant sheaf. As an application, we prove the folklore result of Morel that pi_0 of the motivic localization of the group completion of the stack of finite \'etale schemes is given by the sheaf of unramified Grothendieck-Witt groups.

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Tom Bachmann. 2018-06-28. A1-invariants in Galois cohomology and a claim of Morel. https://arxiv.org/abs/1806.11159

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