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arXiv · 2505.06631

Non-existence of cohomogeneity one Einstein metrics of two summands

Hanci Chi
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Abstract

We prove the non-existence of cohomogeneity one Einstein metrics on a class of compact manifolds arising as double disk bundles, whose principal orbits split into two inequivalent irreducible summands. The proof uses a phase space barrier argument that yields a new obstruction to the existence of closed cohomogeneity one Einstein metrics, even when the principal orbits admit homogeneous Einstein metrics.

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Hanci Chi. 2025-05-10. Non-existence of cohomogeneity one Einstein metrics of two summands. https://arxiv.org/abs/2505.06631

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