Consider the space Hom(ℤn,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(ℤn,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.
Baird, Thomas John  1
@article{10_2140_agt_2007_7_737,
author = {Baird, Thomas John},
title = {Cohomology of the space of commuting n{\textendash}tuples in a compact {Lie} group},
journal = {Algebraic and Geometric Topology},
pages = {737--754},
year = {2007},
volume = {7},
number = {2},
doi = {10.2140/agt.2007.7.737},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2007.7.737/}
}
TY - JOUR AU - Baird, Thomas John TI - Cohomology of the space of commuting n–tuples in a compact Lie group JO - Algebraic and Geometric Topology PY - 2007 SP - 737 EP - 754 VL - 7 IS - 2 UR - http://geodesic.mathdoc.fr/articles/10.2140/agt.2007.7.737/ DO - 10.2140/agt.2007.7.737 ID - 10_2140_agt_2007_7_737 ER -
Baird, Thomas John. Cohomology of the space of commuting n–tuples in a compact Lie group. Algebraic and Geometric Topology, Tome 7 (2007) no. 2, pp. 737-754. doi: 10.2140/agt.2007.7.737
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