Restriction of A-Discriminants and Dual Defect Toric Varieties

Raymond Curran; Eduardo Cattani

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Restriction of A-Discriminants and Dual Defect Toric Varieties

Raymond Curran·Eduardo Cattani

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Abstract

We study the $A$-discriminant of toric varieties. We reduce its computation to the case of irreducible configurations and describe its behavior under specialization of some of the variables to zero. We prove a Gale dual characterization of dual defect toric varieties and deduce from it the classsification of such varieties in codimension less than or equal to four. This classification motivates a decomposition theorem which yields a sufficient condition for a toric variety to be dual defect. For codimension less than or equal to four, this condition is also necessary and we expect this to be the case in general.

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BibTeX RIS

Raymond Curran, Eduardo Cattani. 2006-03-22. Restriction of A-Discriminants and Dual Defect Toric Varieties. https://arxiv.org/abs/math/0510615

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