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arXiv · 1111.7002

Codazzi Tensors with Two Eigenvalue Functions

Gabe Merton
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Abstract

This paper addresses a gap in the classifcation of Codazzi tensors with exactly two eigenfunctions on a Riemannian manifold of dimension three or higher. Derdzinski proved that if the trace of such a tensor is constant and the dimension of one of the the eigenspaces is $n-1$, then the metric is a warped product where the base is an open interval- a conclusion we will show to be true under a milder trace condition. Furthermore, we construct examples of Codazzi tensors having two eigenvalue functions, one of which has eigenspace dimension $n-1$, where the metric is not a warped product with interval base, refuting a remark in \cite{Besse} that the warped product conclusion holds without any restriction on the trace.

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Gabe Merton. 2011-11-29. Codazzi Tensors with Two Eigenvalue Functions. https://arxiv.org/abs/1111.7002

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