𝜁 (Ric)-vector fields on doubly warped product manifolds
Sibel Gerdan Aydın, Moctar Traore, Hakan Mete TaştanWe investigate 𝜁 (Ric)-vector fields on doubly warped product manifolds. We obtain some results when the vector field is also 𝜁 (Ric) on factor manifolds.We prove that if a vector field is a 𝜁 (Ric)-vector field on a doubly warped product manifold, it is also a 𝜁 (Ric)-vector field on the factor manifolds under certain conditions. Also, we show that a vector field on a doubly warped product manifold can be a 𝜁 (Ric)-vector field with some conditions. Moreover we give two important applications of this concept in the Lorentzian settings, which are the doubly warped product generalized Robertson-Walker space-time and doubly warped product standard static space-time.