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arXiv · 2308.04962

Computing Galois cohomology of a real linear algebraic group

Mikhail Borovoi·Willem A. de Graaf
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Abstract

Let G be a linear algebraic group, not necessarily connected or reductive, over the field of real numbers R. We describe a method, implemented on computer, to find the first Galois cohomology set H^1(R,G). The output is a list of 1-cocycles in G. Moreover, we have an implemented algorithm that, given a 1-cocycle z in Z^1(R,G), finds the cocycle in the computed list to which z is equivalent, together with an element of G(C) realizing the equivalence.

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BibTeXRIS

Mikhail Borovoi, Willem A. de Graaf. 2023-08-09. Computing Galois cohomology of a real linear algebraic group. https://doi.org/10.1112/jlms.12906

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