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arXiv · 1405.2122

Projective duality of arrangements with quadratic logarithmic vector fields

Stefan Tohaneanu
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Abstract

In these notes we study hyperplane arrangements having at least one logarithmic derivation of degree two that is not a combination of degree one logarithmic derivations. It is well-known that if a hyperplane arrangement has a linear logarithmic derivation not a constant multiple of the Euler derivation, then the arrangement decomposes as the direct product of smaller arrangements. The next natural step would be to study arrangements with non-trivial quadratic logarithmic derivations. On this regard, we present a computational lemma that leads to a full classification of hyperplane arrangements of rank 3 having such a quadratic logarithmic derivation. These results come as a consequence of looking at the variety of the points dual to the hyperplanes in such special arrangements.

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Stefan Tohaneanu. 2014-05-08. Projective duality of arrangements with quadratic logarithmic vector fields. https://arxiv.org/abs/1405.2122

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