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arXiv · 2110.13062

Galois cohomology and component group of a real reductive group

Mikhail Borovoi·Dmitry A. Timashev
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Abstract

Let G be a connected reductive group over the field of real numbers R. Using results of our previous joint paper, we compute combinatorially the first Galois cohomology set H^1(R,G) in terms of reductive Kac labelings. Moreover, we compute the group of connected components \pi_0 G(R) of the real Lie group G(R) and the maps in exact sequences containing \pi_0 G(R) and H^1(R,G).

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BibTeXRIS

Mikhail Borovoi, Dmitry A. Timashev. 2021-10-25. Galois cohomology and component group of a real reductive group. https://doi.org/10.1007/s11856-023-2526-4

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