The Dirac Spectrum on Manifolds with Gradient Conformal Vector Fields
نویسنده
چکیده
We show that the Dirac operator on a spin manifold does not admit L eigenspinors provided the metric has a certain asymptotic behaviour and is a warped product near infinity. These conditions on the metric are fulfilled in particular if the manifold is complete and carries a non-complete vector field which outside a compact set is gradient conformal and non-vanishing.
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