TY - JOUR T1 - Rigidity for Einstein Manifolds under Bounded Covering Geometry AU - Si , Cuifang AU - Xu , Shicheng JO - Journal of Mathematical Study VL - 2 SP - 145 EP - 163 PY - 2025 DA - 2025/06 SN - 58 DO - http://doi.org/10.4208/jms.v58n2.25.02 UR - https://global-sci.org/intro/article_detail/jms/24207.html KW - Einstein, rigidity, almost nonnegative Ricci curvature, bounded covering geometry, space forms. AB -
In this note, we prove three rigidity results for Einstein manifolds with bounded covering geometry. (1) An almost flat manifold $(M,g)$ must be flat if it is Einstein, i.e. ${\rm Ric}_g =λg$ for some real number $λ.$ (2) A compact Einstein manifold with a non-vanishing and almost maximal volume entropy is hyperbolic. (3) A compact Einstein manifold admitting a uniform local rewinding almost maximal volume is isometric to a space form.