Characteristic varieties and constructible sheaves
Abstract
We explore the relation between the positive dimensional irreducible components of the characteristic varieties of rank one local systems on a smooth surface and the associated (rational or irrational) pencils. Our study, which may viewed as a continuation of D. Arapura's work, yields new geometric insight into the translated components relating them to the multiplicities of curves in the associated pencil, in a close analogy to the compact situation treated by A. Beauville. The new point of view is the key role played by the constructible sheaves naturally arising from local systems.
Cite
@article{arxiv.math/0702871,
title = {Characteristic varieties and constructible sheaves},
author = {Alexandru Dimca},
journal= {arXiv preprint arXiv:math/0702871},
year = {2010}
}
Comments
This new version brings in the orbifold fundamental groups and gives a simple, complete description of the finite group $T(f)$, see Theorem 5.3, which corrects a previous result by Serrano