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FRW models of the universe have been studied in the cosmological theory based on Lyra's manifold. A new class of exact solutions has been obtained by considering a time dependent displacement field for variable deceleration parameter from…

General Relativity and Quantum Cosmology · Physics 2015-06-25 A. Pradhan , J. P. Shahi , C. B. Singh

We propose a new law for the deceleration parameter that varies linearly with time and covers Berman's law where it is constant. Our law not only allows one to generalize many exact solutions that were obtained assuming constant…

General Relativity and Quantum Cosmology · Physics 2012-01-25 Ozgur Akarsu , Tekin Dereli

Cosmological models in Lyra's geometry are constructed and investigated with the assumption of a minimal interaction of matter with the displacement vector field and the dynamical $\Lambda$ - term. Exact solutions of the model equations are…

General Relativity and Quantum Cosmology · Physics 2012-10-04 V. K. Shchigolev

In this paper, we investigate a scalar field Brans-Dicke cosmological model in Lyra's geometry which is based on the modifications in geometrical term as well as energy term of Einstein's field equations. We have examined the validity of…

General Relativity and Quantum Cosmology · Physics 2023-11-15 Rajendra Prasad , Lalit Kumar Gupta , Anil Kumar Yadav

The present study deals with Lyra's geometry in plane symmetric metric discussed in the presence of bulk viscous fluid and one dimensional strings are assumed to be loaded with particles and the particle energy density. The variation of…

General Relativity and Quantum Cosmology · Physics 2023-06-21 M Krishna , SobhanBabu Kappala , R Santhikumar

We studied plane symmetric cosmological model in the presence of quark and strange quark matter with the help of f(R,T) theory. To decipher solutions of Plane symmetric space-time, we used power law relation between scale factor and…

General Relativity and Quantum Cosmology · Physics 2017-03-22 P. K. Agrawal , D. D. Pawar

In this paper the observational consequence of the cosmological models and the expression for the neoclassical tests, luminosity distance, angular diameter distance and look back time are analyzed in the framework of Lyra geometry. It is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. S. Khadekar , Anirudh Pradhan , Kashika Srivastava

In this paper, a general FRW cosmological model has been constructed in $f(R,T)$ gravity reconstruction with variable cosmological constant. A number of solutions to the field equations has been generated by utilizing a form for the Hubble…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Nasr Ahmed , Sultan Z. Alamri

This paper has studied five-dimensional FRW cosmological models for k=-1,0,1in the presence of two perfect fluids namely ordinary baryonic fluid and a bizarre creating dark energy within the framework of Lyra's manifold (Lyra 1951). We have…

General Relativity and Quantum Cosmology · Physics 2023-12-22 Syed Sabanam , Kangujam Priyokumar Singh

A spatially homogeneous anisotropic LRS Bianchi type-I cosmological model is studied in $f(R,T)$ gravity with a special form of Hubble's parameter, which leads to constant deceleration parameter. The parameters involved in the considered…

General Relativity and Quantum Cosmology · Physics 2022-07-20 Binaya K. Bishi , S. K. J. Pacif , P. K. Sahoo , G. P. Singh

In this paper, we have derived the field equations in an extended theory of gravity in an anisotropic space time background and in the presence of magnetic field. The physical and geometrical parameters of the models are determined with…

General Relativity and Quantum Cosmology · Physics 2022-07-19 Sankarsan Tarai , Fakhereh Md. Esmaeili , B. Mishra , S. K. Tripathy

We determine a cosmological model that include a positive acceleration of the Universe and a time decreasing fine structure constant. The present day deceleration parameter is estimated by us, according to our model and the available…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

We applied the theory of regularly varying functions to the analysis of the cosmological parameters for the $\Lambda$CDM model with the matter dominated evolution. Carroll et al. proved in 1992 that for this type of universe with the…

Mathematical Physics · Physics 2017-11-21 Žarko Mijajlović , Nadežda Pejović , Viktor Radović

In this work a new law of varying deceleration parameter of third degree have been proposed. The solutions of the modified field equations have been derived under the newly proposed law of the deceleration parameter. Model exhibits the…

General Relativity and Quantum Cosmology · Physics 2022-08-23 Leishingam Kumrah , S. Surendra Singh , L. Anjana Devi , Md Khurshid Alam

We study an special law for the deceleration parameter, recently proposed by Akarsu and Dereli, in the context of $f(R)$, $f(T)$ and $f(\mathcal{G})$ theories of modified gravity. This law covers the law of Berman for obtaining exact…

General Relativity and Quantum Cosmology · Physics 2013-04-11 F. Darabi

We construct the cosmological model to explain the cosmological constant problem. We built the extension of the standard cosmological model $\Lambda$CDM by consideration of decaying vacuum energy represented by the running cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-08 Marek Szydlowski

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-02 Y. Myrzakulov , Alnadhief H. A. Alfedeel , M. Koussour , S. Muminov , E. I. Hassan , J. Rayimbaev

In this paper, we have proposed a generalized parametrization for the deceleration parameter $q$ in order to study the evolutionary history of the universe. We have shown that the proposed model can reproduce three well known…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Abdulla Al Mamon

The main purpose of the present paper is to investigate LRS Bianchi type I metric in the presence of perfect fluid and dark energy. In order to obtain a deterministic solution of the field equations we have assumed that, the two sources of…

General Relativity and Quantum Cosmology · Physics 2020-03-06 Y. S. Solanke , D. D. Pawar , V. J. Dagwal

With due consideration of reasonable cosmological assumptions within the limit of the present cosmological scenario, we have analysed a spherically symmetric metric in 5D setting within the framework of Lyra manifold. The model universe is…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Pheiroijam Suranjoy Singh , Kangujam Priyokumar Singh
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