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String Cohomology of a Toroidal Singularity

Lev A. Borisov
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Abstract

We construct explicitly regular sequences in the semigroup ring $R=\CC[K]$ of lattice points of the graded cone $K$. We conjecture that the quotients of $R$ by these sequences describe locally string-theoretic cohomology of a toroidal singularity associated to $K$. As a byproduct, we give an elementary proof of the result of Hochster that semigroup rings of rational polyhedral cones are Cohen-Macaulay.

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Lev A. Borisov. 1998-02-10. String Cohomology of a Toroidal Singularity. https://arxiv.org/abs/math/9802052

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