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A note on Tutte polynomials and Orlik-Solomon algebras

Raul Cordovil·David Forge
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Abstract

Let A be a (central) arrangement of hyperplanes in a finite dimension complex vector space V. Let M(A) be the dependence matroid determined by A. The Orlik-Solomon algebra OS(M) of a matroid M is the exterior algebra on the points modulo the ideal generated by circuit boundaries. The algebra OS(M) is isomorphic to the cohomology algebra of the complement in V of the union of the hyperplanes of A. The Tutte polynomial T(x,y) of M is a powerful invariant of the matroid M. When M(A) is a rank three matroid and A is the complexification of a real arrangement, we prove that OS(M) determines T(x,y). This result solves partially a conjecure of M. Falk.

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Raul Cordovil, David Forge. 2002-03-15. A note on Tutte polynomials and Orlik-Solomon algebras. https://arxiv.org/abs/math/0203152

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