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arXiv · 2107.06609

Homogeneous Einstein Metrics and Butterflies

Christoph Böhm·Megan M. Kerr
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Abstract

M.~M.~Graev associated in \cite{Gr} to a compact homogeneous space $G/H$ a nerve $\XGH$, whose non-contractibility implies the existence of a $G$-invariant Einstein metric on $G/H$. The nerve $\XGH$ is a compact semi-algebraic set, defined purely Lie theoretically by intermediate subgroups. In this paper we present a detailed description of the work of Graev and the curvature estimates of \cite{Bo}.

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Christoph Böhm, Megan M. Kerr. 2021-07-14. Homogeneous Einstein Metrics and Butterflies. https://arxiv.org/abs/2107.06609

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