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arXiv · 1205.1566

Moment Angle Complexes and Big Cohen-Macaulayness

Abstract

Let Z_K be the moment angle complex associated to a simplicial complex K, with the canonical torus T-action. In this paper, we prove that, for any possibly disconnected subgroup G of T, G-equivariant cohomology of Z_K over the integer Z is isomophic to the Tor-module Tor_{H(BR;Z)}(Z[K],Z) as graded modules, where Z_[K] is the Stanley-Reisner ring of K. Based on this, we prove that the surjectivity of the natural map H_T(Z_K;Z) to H_G(Z_K;Z) is equivalent to the vanishing of Tor^{H(BR;Z)}_1(Z[K],Z). Since the integral cohomology of various toric orbifolds can be identified with H_G(Z_K;Z), we studied the conditions for the cohomology of a toric orbifold to be a quotient of its equivariant cohomology by linear terms.

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BibTeXRIS

Shisen Luo, Tomoo Matsumura, W. Frank Moore. 2012-06-11. Moment Angle Complexes and Big Cohen-Macaulayness. https://doi.org/10.2140/agt.2014.14.379

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