Remarks on η-parallel real hypersurfaces in ℂP2 and ℂH2
Abstract
Let M be a three-dimensional real hypersurface in a nonflat complex space form of complex dimension two. In this paper, we prove that M is η-parallel with two distinct principal curvatures at each point if and only if it is locally congruent to a geodesic sphere in ℂP2 or a horosphere, a geodesic sphere or a tube over totally geodesic complex hyperbolic plane in ℂH2. Moreover, η-parallel real hypersurfaces in ℂP2 and ℂH2 under some other conditions are classified and these results extend Suh’s in [Characterizations of real hypersurfaces in complex space forms in terms of Weingarten map, Nihonkai Math. J. 6 (1995) 63–79] and Kon–Loo’s in [On characterizations of real hypersurfaces in a complex space form with η-parallel shape operator, Canad. Math. Bull. 55 (2012) 114–126].