Niloufar HOSSEINPOUR KASHANI, Behzad NAJAFI

On nearly Kenmotsu manifolds

We prove that on a nearly Kenmotsu manifold a second-order symmetric closed recurrent tensor is a multiple of the associated metric tensor. We then find the necessary condition under which a vector field on a nearly Kenmotsu manifold will be a strict contact or Killing vector field. Finally, we prove that every f-recurrent nearly Kenmotsu manifold is an Einstein manifold and every locally f-recurrent nearly Kenmotsu manifold is a manifold of constant curvature -1 .

Anahtar Kelimeler:

Almost contact metric, Kenmotsu manifold, nearly Kenmotsu manifold

On nearly Kenmotsu manifolds

Keywords:

Almost contact metric, Kenmotsu manifold, nearly Kenmotsu manifold,

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