Abstract
In this paper, we provide new necessary and sufficient conditions for the existence of Kähler–Einstein metrics on small deformations of a Fano Kähler–Einstein manifold. We also show that the Weil–Petersson metric can be approximated by the Ricci curvatures of the canonical \(L^2\) metrics on the direct image bundles. In addition, we describe the plurisubharmonicity of the energy functional of harmonic maps on the Kuranishi space of the deformation of compact Kähler–Einstein manifolds of general type.
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Acknowledgements
We would like to thank T. Collins and J. Keller for their helpful comments on an earlier version of the paper. We would also like to thank the anonymous referee for providing helpful comments. The second named author would also like to thank S. K. Donaldson, D. H. Phong, R. Schoen and X. Wang for helpful discussions.
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Communicated by Ngaiming Mok.
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Research of H.-D. Cao and X. Sun was supported in part by Simons Foundation Grants.
Research of Y. Zhang was supported by Tsinghua University Initiative Scientific Research Program.
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Cao, HD., Sun, X., Yau, ST. et al. On deformations of Fano manifolds. Math. Ann. 383, 809–836 (2022). https://doi.org/10.1007/s00208-021-02226-2
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DOI: https://doi.org/10.1007/s00208-021-02226-2