Abstract: In this paper, we show that every almost Einstein-Hermitian 4-manifold (i.e., almost Hermitian 4-manifold with J-invariant Ricci tensor and harmonic Weyl tensor) is either Einstein or Hermitian. Consequently, we obtain that any almost Einstein-Hermitian 4-manifold which is not Einstein must be Hermitian and that every almost Einstein-Hermitian 4-manifold which is not Hermitian is Einstein. In contrast to the 4-dimensional case, there exists an almost Einstein-Hermitian manifold of dimension which is neither Einstein nor Hermitian.
|
Keywords and phrases: almost Einstein-Hermitian 4-manifold, Einstein, Hermitian, almost Einstein-Hermitian manifold of dimensio
Received: October 22, 2024; Accepted: November 18, 2024; Published: December 24, 2024
How to cite this article: Jaeman Kim, Almost Einstein-Hermitian manifolds, JP Journal of Geometry and Topology 30(2) (2024), 119-130. https://doi.org/10.17654/0972415X24008
This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License
References: [1] A. L. Besse, Einstein Manifolds, Springer, Berlin, 1987. [2] G. Catino, Generalized quasi-Einstein manifolds with harmonic Weyl tensor, Math. Z. 271(3-4) (2012), 751-756. [3] J. Kim, On Einstein Hermitian manifolds, Monatsh. Math. 152 (2007), 251-254. [4] O. Muskarov, On Hermitian surfaces with J-invariant Ricci tensor, J. Geom. 72 (2001), 151-156. [5] E. Ribeiro, Rigidity of four-dimensional compact manifolds with harmonic Weyl tensor, Ann. Mat. Pura Appl. (4) 195 (2016), 2171-2181. [6] T. Sato, Some remarks on almost Kähler 4-manifolds of pointwise constant holomorphic sectional curvature, Kodai Math. J. 22 (1999), 286-303. [7] K. Yano, Differential Geometry on Complex and Almost Complex Spaces, Pergamon Press, 1965.
|