A note on the cohomology of the Langlands group

Fan, Edward

doi:10.1090/S0002-9947-2014-06230-2

A note on the cohomology of the Langlands group
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by Edward S.T. Fan; with an appendix by M. Flach PDF

Trans. Amer. Math. Soc. 367 (2015), 2905-2920 Request permission

Abstract:

We begin with a comparison of various cohomology theories for topological groups. Using the continuity result for Moore cohomology, we establish a Hochschild-Serre spectral sequence for a slightly larger class of groups. We use these properties to compute the cohomology of the Langlands group of a totally imaginary field. The appendix answers a question raised by Flach concerning the cohomological dimension of the group $\mathbb {R}$.

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