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arXiv · 1112.1012

Mixed Discriminants

Eduardo Cattani·Maria Angelica Cueto·Alicia Dickenstein·Sandra Di Rocco·Bernd Sturmfels
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Abstract

The mixed discriminant of n Laurent polynomials in n variables is the irreducible polynomial in the coefficients which vanishes whenever two of the roots coincide. The Cayley trick expresses the mixed discriminant as an A-discriminant. We show that the degree of the mixed discriminant is a piecewise linear function in the Plucker coordinates of a mixed Grassmannian. An explicit degree formula is given for the case of plane curves.

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Eduardo Cattani, Maria Angelica Cueto, Alicia Dickenstein, Sandra Di Rocco, Bernd Sturmfels. 2011-12-05. Mixed Discriminants. https://arxiv.org/abs/1112.1012

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