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Autori: D.C. Cohen, A.I. Suciu
Editorial: Geometry & Topology Monographs, 13, p.105-146, 2008.
We study the topology of the boundary manifold of a line arrangement in CP^2, with emphasis on the fundamental group G and associated invariants. We determine the Alexander polynomial Delta(G), and more generally, the twisted Alexander polynomial associated to the abelianization of G and an arbitrary complex representation. We give an explicit description of the unit ball in the Alexander norm, and use it to analyze certain Bieri–Neumann–Strebel invariants of G. From the Alexander polynomial, we also obtain a complete description of the first characteristic variety of G. Comparing this with the corresponding resonance variety of the cohomology ring of G enables us to characterize those arrangements for which the boundary manifold is formal.
Cuvinte cheie: line arrangement, graph manifold, fundamental group, twisted Alexander polynomial, BNS invariant, cohomology ring, holonomy Lie algebra, characteristic variety, resonance variety, tangent cone, formality