Cyriaque ATINDOGBE, Oscar LUNGIAMBUDILA, Joël TOSSA

Scalar curvature and symmetry properties of lightlike submanifolds}

In this paper, the induced Ricci tensor and the extrinsic scalar curvature on lightlike submanifolds are obtained. This scalar quantity extend the result given by C. Atindogbe in [1]. An example of extrinsic scalar curvature on one class of 2-degenerate manifolds is provided. We investigate lightlike submanifolds which are locally symmetric, semi-symmetric, Ricci semi-symmetric in indefinite spaces form. In the coisotropic case, we show that, under some conditions, these lightlike submanifolds are totally geodesic.

Anahtar Kelimeler:

Key words: Extrinsic scalar curvature, locally symmetric lightlike submanifold, semi-symmetric lightlike submanifold, Ricci semi-symmetric lightlike submanifold

Scalar curvature and symmetry properties of lightlike submanifolds}

Keywords:

Key words: Extrinsic scalar curvature, locally symmetric lightlike submanifold, semi-symmetric lightlike submanifold, Ricci semi-symmetric lightlike submanifold,

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