T. Q. Binh: Institute of Mathematics and Informatics, Lajos Kossuth University, H-4010 Debrecen, P.O. Box 12, Hungary, binh@math.klte.hu; U. C. De and A. A. Shaikh, Department of Mathematics, University of Kalyani, Kalyani-741235, W.B., India, ucde@klyuniv.ernet.in.
Abstract: In this paper we shall give necessary conditions for the compatibility of several $K$-contact structures with weak symmetry and weak Ricci-symmetry and weak Ricci-symmetry, provided they do not reduce to the common local symmetry, that is, they are proper. Thus weak symmetry and weak Ricci-symmetry are weaker than pseudosymmetry and pseudo Ricci-symmetry respectively.
Keywords: Weakly symmetric Riemannian manifold, K-contact manifold
Classification (MSC91): 53C15; 53C25
Full text of the article: