$L^2$ and intersection cohomologies for the reductive representation of the fundamental groups of quasiprojective manifolds with unipotent local monodromy

Abstract

Let $X$ be a projective manifold, and $D$ be a normal crossing divisor of $X$. By Jost-Zuo's theorem that if we have a reductive representation $ρ$ of the fundamental group $π_{1}(X^{*})$ with unipotent local monodromy, where $X^*=X-D$, then there exists a tame pluriharmonic metric $h$ on the flat bundle $\mathcal V$ associated to the local system $\mathbb V$ obtain from $ρ$ over $X^*$. Therefore, we get a harmonic bundle $(E, θ, h)$, where $θ$ is the Higgs field, i.e. a holomorphic section of $End(E)\otimesΩ^{1,0}_{X^*}$ satisfying $θ^2=0$. In this paper, we study the harmonic bundle $(E,θ,h)$ over $X^*$. We are going to prove that the intersection cohomology $IH^{k}(X; \mathbb V)$ is isomorphic to the $L^{2}$-cohomology $H^{k}(X, (\mathcal A_{(2)}^{\cdot}(X,\mathcal V), \mathbb D))$.

This paper has been withdrawn by the author due to a crucial sign error in lemma 3.7