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Local rigidity of 3-dimensional cone-manifolds

Hartmut Weiss
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Abstract

We investigate the local deformation space of 3-dimensional cone-manifold structures of constant curvature $\kappa \in \{-1,0,1\}$ and cone-angles $\leq \pi$. Under this assumption on the cone-angles the singular locus will be a trivalent graph. In the hyperbolic and the spherical case our main result is a vanishing theorem for the first $L^2$-cohomology group of the smooth part of the cone-manifold with coefficients in the flat bundle of infinitesimal isometries. We conclude local rigidity from this. In the Euclidean case we prove that the first $L^2$-cohomology group of the smooth part with coefficients in the flat tangent bundle is represented by parallel forms.

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Hartmut Weiss. 2005-04-06. Local rigidity of 3-dimensional cone-manifolds. https://arxiv.org/abs/math/0504114

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