$L^2$-Serre duality on singular complex spaces and rational singularities

Abstract

In the present paper, we devise a version of topological $L^2$-Serre duality for singular complex spaces with arbitrary singularities. This duality is used to deduce various new $L^2$-vanishing theorems for the $\bar{\partial }$-equation on singular spaces. It is shown that complex spaces with rational singularities behave quite tame with respect to the $\bar{\partial }$-equation in the $L^2$-sense. More precisely: a singular point is rational if and only if the $L^2$-$\bar{\partial }$-complex is exact in this point. So, we obtain an $L^2$-$\bar{\partial }$-resolution of the structure sheaf in rational singular points.

30 pages; completely revised version with more details on the topological difficulties