The Monodromy Conjecture for hyperplane arrangements

The Monodromy Conjecture for Hyperplane Arrangements

The Monodromy Conjecture asserts that if c is a pole of the local topological zeta function of a hypersurface, then exp(2πic) is an eigenvalue of the monodromy on the cohomology of the Milnor fiber. A stronger version of the conjecture asserts that every such c is a root of the Bernstein-Sato polynomial of the hypersurface. In this note we prove the weak version of the conjecture for hyperplane...

The Braid Monodromy of Plane Algebraic Curves and Hyperplane Arrangements

To a plane algebraic curve of degree n, Moishezon associated a braid monodromy homomorphism from a finitely generated free group to Artin’s braid group Bn. Using Hansen’s polynomial covering space theory, we give a new interpretation of this construction. Next, we provide an explicit description of the braid monodromy of an arrangement of complex affine hyperplanes, by means of an associated “b...

The Topology of Hyperplane Arrangements

Complex Hyperplane Arrangements

We were fortunate to spend the 2004 fall semester in residence at MSRI, participating in the program on Hyperplane Arrangements and Applications. It was an intense, stimulating, productive, enlightening, eventful and most enjoyable experience. It was especially so for us long-timers in the field because the program truly marked a coming-of-age in the evolution of the subject from relative obscu...

Extended Linial Hyperplane Arrangements for Root Systems and a Conjecture of Postnikov and Stanley

A hyperplane arrangement is said to satisfy the “Riemann hypothesis” if all roots of its characteristic polynomial have the same real part. This property was conjectured by Postnikov and Stanley for certain families of arrangements which are defined for any irreducible root system and was proved for the root system An−1. The proof is based on an explicit formula [1, 2, 11] for the characteristi...