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Intersection Homology of Toric Varieties and a Conjecture of Kalai

Tom C. Braden·Robert D. MacPherson
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Abstract

We prove that the intersection homology Poincare' polynomial P(X) of an affine toric variety X is bounded below by the product P(Y)P(X/Y), where Y is the closure of any orbit in X and X/Y is a slice transverse to the orbit. This proves a combinatorial conjecture of Kalai for rational polytopes.

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Tom C. Braden, Robert D. MacPherson. 1997-04-13. Intersection Homology of Toric Varieties and a Conjecture of Kalai. https://arxiv.org/abs/alg-geom/9704014

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