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arXiv · 0710.2302

Freeness of equivariant cohomology and mutants of compactified representations

Matthias Franz·Volker Puppe
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Abstract

We survey generalisations of the Chang-Skjelbred Lemma for integral coefficients. Moreover, we construct examples of manifolds with actions of tori of rank > 2 whose equivariant cohomology is torsion-free, but not free. This answers a question of Allday's. The "mutants" we construct are obtained from compactified representations and involve Hopf bundles in a crucial way.

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BibTeXRIS

Matthias Franz, Volker Puppe. 2007-10-16. Freeness of equivariant cohomology and mutants of compactified representations. https://doi.org/10.1090/conm%2F460%2F09012

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