Results 21 to 30 of about 1,975 (257)
A cosmological model with time dependent Λ, G and viscous fluid in general relativity
Frontiers in Astronomy and Space Sciences, 2022 In this paper, we investigate Bianchi type − V cosmological models with bulk viscous fluid and time varying cosmological Λ and Newtonian G parameters.
Rishi Kumar Tiwari +6 more
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Self-dual cosmological Bianchi IX and VIII metrics
Advances in Theoretical and Mathematical Physics, 2022 We show that self-dual Bianchi IX and VIII cosmological models are described by the Nahm dynamical system for an appropriate type of matrices. We construct the general solutions in the case of the diagonal reductions of the corresponding Nahm equations and give the explicit expressions for the corresponding self-dual metrics in the Euclidean and in the
Mikovic, A., Manojlovic, N.
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LRS Bianchi type I models with anisotropic dark energy and constant deceleration parameter
, 2010 Locally rotationally symmetric Bianchi type I cosmological models are examined in the presence of dynamically anisotropic dark energy and perfect fluid.
Akarsu Ö., Kılınç C.B.
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Exotic massive 3D gravities from truncation
Journal of High Energy Physics, 2019 We introduce a systematic way of constructing 3D exotic massive gravity theories in the first order formulation. Our method is based on truncating a single degree of freedom in the parity odd gravity models found earlier [1] and supplementing it with ...
Hamid Reza Afshar, Nihat Sadik Deger
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Einstein-Weyl structures and Bianchi metrics [PDF]
Classical and Quantum Gravity, 1998 We analyse in a systematic way the (non-)compact four dimensional Einstein-Weyl spaces equipped with a Bianchi metric. We show that Einstein-Weyl structures with a Class A Bianchi metric have a conformal scalar curvature of constant sign on the manifold.
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Energy and Momentum of Bianchi Type VIh Universes
Advances in High Energy Physics, 2015 We obtain the energy and momentum of the Bianchi type VIh universes using different prescriptions for the energy-momentum complexes in the framework of general relativity.
S. K. Tripathy +5 more
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The evolution of time-dependent Λ and G in multi-fluid Bianchi type-I cosmological models
Open Astronomy, 2022 In this work, cosmological solutions based on the time-dependent cosmological (Λ\Lambda ) and Newtonian (GG) running “constants” in the Bianchi type-I spacetime are investigated vis-à-vis known cosmological data. The observationally known values of Ωm,Ωr{
Alfedeel Alnadhief H. A., Abebe Amare
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The momentum 4-vector imparted by gravitational waves in Bianchi-type metrics [PDF]
Astrophysics and Space Science, 2006 This paper has been removed by arXiv administrators because it plagiarizes gr-qc/0008034, "The Energy Distribution of the Bianchi Type I Universe," by I. Radinschi; Phys. Rev. D 41, 1086 (1990), "Energy associated with a Kerr-Newman black hole," by K.S. Virbhadra; and Braz. J. Phys.
Havare, A., Korunur, M., Salti, M.
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Kasner type magnetized string cosmological models in f(R,T) gravity [PDF]
Serbian Astronomical Journal, 2018 The Bianchi-I Kasner type metric with cosmic string and magnetic field in the framework of the f(R,T) theory of gravitation is considered. Three different functional forms of the function f(R,T) are chosen for investigation.
Hatkar S.P., Gore S.V., Katore S.D.
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Constraints of Anisotropy on Warm Power-Law Ination in Light of Planck Results [PDF]
Iranian Journal of Astronomy and Astrophysics, 2021 In this article, we examine the effects of anisotropy on a model of canonical warm inflation with the power-law potential. And we have compared the limitations of this model with Planck's results.
Zahra Ghadiry +2 more
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