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Cohomology of the space of commuting n-tuples in a compact Lie group

Thomas Baird
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Abstract

Consider the space Hom(Z^n,G) of pairwise commuting n-tuples of elements in a compact Lie group G. This forms a real algebraic variety, which is generally singular. In this paper, we construct a desingularization of the generic component of Hom(Z^n,G), which allows us to derive formulas for its ordinary and equivariant cohomology in terms of the Lie algebra of a maximal torus in G and the action of the Weyl group. This is an application of a general theorem concerning G-spaces for which every element is fixed by a maximal torus.

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Thomas Baird. 2007-02-19. Cohomology of the space of commuting n-tuples in a compact Lie group. https://doi.org/10.2140/agt.2007.7.737

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