Bayer-Macri decomposition on Bridgeland moduli spaces over surfaces

摘要

We find a decomposition formula of the local Bayer-Macri map for the nef line bundle theory on the Bridgeland moduli space over a surface. If there is a global Bayer-Macri map, then such a decomposition gives a precise correspondence from Bridgeland walls to Mori walls. As an application, we compute the nef cone of the Hilbert scheme S-[n] of n-points over special kinds of a fibered surface S of Picard rank 2.