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arXiv · 1207.4839

The greatest Ricci lower bound, conical Einstein metrics and the Chern number inequality

Jian Song·Xiaowei Wang
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Abstract

We partially confirm a conjecture of Donaldson relating the greatest Ricci lower bound $R(X)$ to the existence of conical Kahler-Einstein metrics on a Fano manifold $X$. In particular, if $D\in |-K_X|$ is a smooth simple divisor and the Mabuchi $K$-energy is bounded below, then there exists a unique conical Kahler-Einstein metric satisfying $Ric(g) = βg + (1-β) [D]$ for any $β\in (0,1)$. We also construct unique smooth conical toric Kahler-Einstein metrics with $β=R(X)$ and a unique effective Q-divisor $D\in [-K_X]$ for all toric Fano manifolds. Finally we prove a Miyaoka-Yau type inequality for Fano manifolds with $R(X)=1$.

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Jian Song, Xiaowei Wang. 2012-07-20. The greatest Ricci lower bound, conical Einstein metrics and the Chern number inequality. https://doi.org/10.2140/gt.2016.20.49

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