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arXiv · 1806.08311

Cohen-Macaulay Du Bois singularities with a torus action of complexity one

Antonio Laface·Alvaro Liendo·Joaquín Moraga
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Abstract

Using Altmann-Hausen-Suss description of $\mathbb{T}$-varieties via divisorial fans and K\'ovacs-Schwede-Smith characterization of Du Bois singularities, we study Cohen-Macaulay Du Bois $\mathbb{T}$-singularities of complexity one. We exhibit cohomological criteria for a $\mathbb{T}$-variety to be Cohen-Macaulay and Du Bois in terms of polyhedral divisors. We give an example of a Cohen-Macaulay Du Bois singularity of complexity one which does not have rational singularities.

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Antonio Laface, Alvaro Liendo, Joaquín Moraga. 2018-06-21. Cohen-Macaulay Du Bois singularities with a torus action of complexity one. https://arxiv.org/abs/1806.08311

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