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arXiv · 1211.1224

Combinatorial stratifications and minimality of 2-arrangements

Karim A. Adiprasito
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Abstract

We prove that the complement of any affine 2-arrangement in R^d is minimal, that is, it is homotopy equivalent to a cell complex with as many i-cells as its i-th rational Betti number. For the proof, we provide a Lefschetz-type hyperplane theorem for complements of 2-arrangements, and introduce Alexander duality for combinatorial Morse functions. Our results greatly generalize previous work by Falk, Dimca--Papadima, Hattori, Randell, and Salvetti--Settepanella and others, and they demonstrate that in contrast to previous investigations, a purely combinatorial approach suffices to show minimality and the Lefschetz Hyperplane Theorem for complements of complex hyperplane arrangements.

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BibTeXRIS

Karim A. Adiprasito. 2012-11-06. Combinatorial stratifications and minimality of 2-arrangements. https://doi.org/10.1112/jtopol%2Fjtu018

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