Linear free divisors and quiver representations

Ragnar-Olaf Buchweitz; David Mond

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arXiv · math/0509221

Linear free divisors and quiver representations

Ragnar-Olaf Buchweitz·David Mond

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Abstract

Linear free divisors are free divisors, in the sense of K.Saito, with linear presentation matrix (example: normal crossing divisors). Using techniques of deformation theory on representations of quivers, we exhibit families of linear free divisors as discriminants in representation spaces for real Schur roots of a finite quiver. We review some basic material on quiver representations, and explain in detail how to verify whether the discriminant is a free divisor and how to determine its components and their equations, using techniques of A. Schofield. As an illustration, the linear free divisors that arise as the discriminant from the highest roots of Dynkin quivers of type E7 and E8 are treated explicitly.

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Ragnar-Olaf Buchweitz, David Mond. 2005-09-09. Linear free divisors and quiver representations. https://arxiv.org/abs/math/0509221

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