Abstract
On an almost Hermitian manifold, there are two Hermitian scalar curvatures associated with a canonical Hermitian connection. In this paper, two explicit formulas on these two scalar curvatures are obtained in terms of the Riemannian scalar curvature, norms of the components of the covariant derivative of the fundamental 2-form with respect to the Levi-Civita connection, and the codifferential of the Lee form. Then we use them to get characterization results of the Kähler metric, the balanced metric, the locally conformal Kähler metric or the k-Gauduchon metric. As corollaries, we show partial results related to a problem given by Lejmi and Upmeier (2020) and a conjecture by Angella et al. (2018).
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Acknowledgements
This work was supported by National Natural Science Foundation of China (Grant Nos. 10831008, 11025103 and 11501505). The second author thanks Professor Jiagui Peng and Professor Xiaoxiang Jiao for their helpful suggestions and encouragement. Part of this work was done while the second author was visiting Laboratory of Mathematics for Nonlinear Science, Fudan University. The second author thanks it for the warm hospitality and support.
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Fu, J., Zhou, X. Scalar curvatures in almost Hermitian geometry and some applications. Sci. China Math. 65, 2583–2600 (2022). https://doi.org/10.1007/s11425-021-1943-8
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DOI: https://doi.org/10.1007/s11425-021-1943-8
Keywords
- J-scalar curvature
- canonical Hermitian connection
- Hermitian scalar curvature
- the first Chern form
- balanced metric
- k-Gauduchon metric