Seshadri fibrations of algebraic surfaces
arXiv:0709.2592
Abstract
We refine results of Hwang, Keum and Szemberg, Tutaj-Gasinska which relate local invariants - Seshadri constants - of ample line bundles on surfaces to the global geometry - fibration structure. We show that the same picture emerges when looking at Seshadri constants measured at any finite subset of the given surface.
8 pages, to appear in Math. Nachr