Results 31 to 40 of about 63,399 (238)
On the Almost $\eta-$Ricci Solitons on Pseudosymmetric Lorentz Generalized Sasakian Space Forms
Universal Journal of Mathematics and Applications, 2023 In this paper, we consider Lorentz generalized Sasakian space forms admitting almost $\eta-$Ricci solitons in some curvature tensors. Ricci pseudosymmetry concepts of \ Lorentz generalized Sasakian space forms admitting $\eta-$Ricci soliton have ...
Mehmet Atçeken, Tuğba Mert
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Multidimensional gravity with higher derivatives and inflation
Physics Letters B, 2020 We elaborate on the inflationary model starting from multidimensional Lagrangian and gravity with second-order curvature terms. The effective scalar field is related to the Ricci scalar of extra dimensions.
Júlio C. Fabris +2 more
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η-Ricci Solitons on Kenmotsu 3-Manifolds
Annals of the West University of Timisoara: Mathematics and Computer Science, 2018 In the present paper we study η-Ricci solitons on Kenmotsu 3-manifolds. Moreover, we consider η-Ricci solitons on Kenmotsu 3-manifolds with Codazzi type of Ricci tensor and cyclic parallel Ricci tensor.
De Krishnendu, De Uday Chand
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On Ricci tensors of Randers metrics
Journal of Geometry and Physics, 2010 In this paper, we study Randers metrics and find a condition on Ricci tensor of these metrics to be Berwaldian. This generalize Shen's Theorem which says: every R- at complete Randers metric is locally Minkowskian. Then we find a necessary and sufficient condition on Ricci tensor under which a Randers metric of scalar ag curvature is of zero ag ...
Tayebi, A., Peyghan, E.
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η-Ricci Solitons on Sasakian 3-Manifolds
Annals of the West University of Timisoara: Mathematics and Computer Science, 2017 In this paper we study η-Ricci solitons on Sasakian 3-manifolds. Among others we prove that an η-Ricci soliton on a Sasakian 3-manifold is an η-Einstien manifold.
Majhi Pradip +2 more
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RICCI and Matter Collineations of SOM-ROY Chaudhary Symmetric Space Time
Mehran University Research Journal of Engineering and Technology, 2018 gThis paper is devoted to explore the RICCI and MCs (Matter Collineations of the Som-Ray Chaudhary spacetime. The spacetime under consideration is one of the spatially homogeneous and rotating spacetimes.
Muhammad Ramzan +2 more
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Almost $\eta-$Ricci Solitons on Pseudosymmetric Lorentz Sasakian Space Forms
Communications in Advanced Mathematical Sciences, 2023 In this paper, we consider pseudosymmetric Lorentz Sasakian space forms admitting almost $\eta-$Ricci solitons in some curvature tensors. Ricci pseudosymmetry concepts of Lorentz Sasakian space forms admits $\eta-$Ricci soliton have introduced according ...
Mehmet Atçeken, Tuğba Mert
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Scalar–tensor gravitation and the Bakry–Émery–Ricci tensor [PDF]
Classical and Quantum Gravity, 2013 The Bakry-Emery generalized Ricci tensor arises in scalar-tensor gravitation theories in the conformal gauge known as the Jordan frame. Recent results from the mathematics literature show that standard singularity and splitting theorems that hold when an energy condition is applied in general relativity also hold when that energy condition is applied ...
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Variational theory of the Ricci curvature tensor dynamics
European Physical Journal C: Particles and Fields, 2021 In this letter a new Lagrangian variational principle is proved to hold for the Einstein field equations, in which the independent variational tensor field is identified with the Ricci curvature tensor $$R^{\mu \nu }$$ R μ ν rather than the metric tensor
Claudio Cremaschini +3 more
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Palatini approach to Born-Infeld-Einstein theory and a geometric description of electrodynamics [PDF]
, 2003 The field equations associated with the Born-Infeld-Einstein action are derived using the Palatini variational technique. In this approach the metric and connection are varied independently and the Ricci tensor is generally not symmetric.
D.E. Davis, Jr. +10 more
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