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arXiv · 1510.07384

K\"ahler-Einstein metrics on group compactifications

Thibaut Delcroix
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Abstract

We obtain a necessary and sufficient condition of existence of a K{\"a}hler-Einstein metric on a $G\times G$-equivariant Fano compactification of a complex connected reductive group $G$ in terms of the associated polytope. This condition is not equivalent to the vanishing of the Futaki invariant. The proof relies on the continuity method and its translation into a real Monge-Amp{\`e}re equation, using the invariance under the action of a maximal compact subgroup $K\times K$.

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Thibaut Delcroix. 2015-10-26. K\"ahler-Einstein metrics on group compactifications. https://doi.org/10.1007/s00039-017-0394-y

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