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arXiv · 1906.02087

Degree 3 unramified cohomology of classifying spaces for exceptional groups

Sanghoon Baek
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Abstract

Let $G$ be a reductive group defined over an algebraically closed field of characteristic $0$ such that the Dynkin diagram of $G$ is the disjoint union of diagrams of types $G_{2}, F_{4}, E_{6}, E_{7}, E_{8}$. We show that the degree $3$ unramified cohomology of the classifying space of $G$ is trivial. In particular, combined with articles by Merkurjev \cite{Mer17} and the author \cite{Baek}, this completes the computations of degree $3$ unramified cohomology and reductive invariants for all split semisimple groups of a homogeneous Dynkin type.

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Sanghoon Baek. 2019-06-05. Degree 3 unramified cohomology of classifying spaces for exceptional groups. https://arxiv.org/abs/1906.02087

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