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In this paper, the dynamical behavior of the accelerated expansion of the universe is discussed within the framework of $f(T)$ gravity, considering power law functional form of $ f(T)=\alpha (-T)^{n}$. Two distinct redshift-dependent…

General Relativity and Quantum Cosmology · Physics 2025-08-29 Shivank Pal , Romanshu Garg , Gyan Prakash Singh , Gauree Shanker

We consider the cosmological evolution of a bulk scalar field and ordinary matter living on the brane world in the light of the constraints imposed by the matter dominated cosmological evolution and a small cosmological constant now. We…

High Energy Physics - Theory · Physics 2016-09-06 Ph. Brax , A. C. Davis

We study the accelerated expansion phase of the universe by using the {\textit{kinematic approach}}. In particular, the deceleration parameter $q$ is parametrized in a model-independent way. Considering a generalized parametrization for…

General Relativity and Quantum Cosmology · Physics 2018-10-22 Abdulla Al Mamon , Kazuharu Bamba

The expansion of the Universe is accelerated as testified by observations of SNeIa at varying redshifts. Explanations of this acceleration are of two kinds: modifications of Einstein gravity or new forms of energy. An example of modified…

Astrophysics · Physics 2011-11-10 M. Roos

A proposal to study the original and new agegraphic dark energy in DGP braneworld cosmology is presented in this work. To verify our model with the observational data, the model is constrained by a variety of independent measurements such…

General Relativity and Quantum Cosmology · Physics 2016-06-08 H. Farajollahi , A. Ravanpak , G. F. Fadakar

The cosmic curvature density parameter has been constrained in the present work independent of any background cosmological model. The reconstruction is performed adopting the non-parametric Gaussian Processes (GP). The constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-18 Purba Mukherjee , Narayan Banerjee

This paper is devoted to study some holographic dark energy models in the context of Chern-Simon modified gravity by considering FRW universe. We analyze the equation of state parameter using Granda and Oliveros infrared cut-off proposal…

General Relativity and Quantum Cosmology · Physics 2017-08-31 M. Jamil Amir , Sarfraz Ali

The evolution of the dark energy parameter within the scope of a spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model filled with perfect fluid and dark energy components is studied by generalizing the recent results…

General Physics · Physics 2014-03-11 Anirudh Pradhan

A simple speed-up cosmology model is proposed to account for the dark energy puzzle. We condense contributions from dark energy and curvature term into one effective parameter in order to reduce parameter degeneracies and to find any…

Astrophysics · Physics 2007-10-10 Xin-He Meng , Meng Su , Zheng Wang

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

We consider a holographic dark energy model, with a varying parameter, n, which evolves slowly with time. We obtain the differential equation describing evolution of the dark energy density parameter, $\Omega_d$, for the flat and non-flat…

General Relativity and Quantum Cosmology · Physics 2015-01-28 Bushra Majeed , Mubasher Jamil , Azad A. Siddiqui

The self-accelerating braneworld model (DGP) seems to provide a simple alternative to the the standard $\Lambda$CDM cosmology to explain the current cosmic acceleration, which is strongly indicated by measurements of Type Ia supernovae, as…

Astrophysics · Physics 2009-11-13 Zong-Hong Zhu , Mauro Sereno

We investigate the evolution of matter density perturbations within a fractional cosmological framework inspired by fractal space-time constructions in field theory, where a deformation of the integration measure induces non-locality and…

General Relativity and Quantum Cosmology · Physics 2026-04-24 S. M. M. Rasouli

We investigate the evolution of the relic density for asymmetric dark matter incorporating self annihilation processes in both the shear-dominated universe and Gauss-Bonnet braneworld. Under the same conditions where the ratio of final…

High Energy Physics - Phenomenology · Physics 2025-05-08 Qiquan Li , Hoernisa Iminniyaz , Fangyu Liu

We show that the equations of motion governing the evolution of a collisionless gravitating system of particles in an expanding universe can be cast in a form which is almost independent of the cosmological density parameter, $\Omega$, and…

Astrophysics · Physics 2020-11-25 Adi Nusser , Jörg M. Colberg

In this paper, we have investigated the anisotropic behavior of the accelerating universe in Bianchi V space time in the frame work of General Relativity (GR). The matter field we have considered is of two non interacting fluids i.e. the…

General Relativity and Quantum Cosmology · Physics 2018-03-30 B. Mishra , P. K. Sahoo , Pratik P. Ray

We study the shear dynamics of higher dimensional Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) cosmology by considering a non-perfect fluid which exerts different pressure in the normal and extra dimensions. We generalise the definition…

General Relativity and Quantum Cosmology · Physics 2015-12-09 Isha Pahwa , Hemwati Nandan , Umananda Dev Goswami

We investigate the evolution of a universe with a decaying cosmological term (vacuum energy) that is assumed to be a function of the scale factor. In this model, while the cosmological term increases to the early universe, the radiation…

Astrophysics · Physics 2008-11-26 Riou Nakamura , Masa-aki Hashimoto , Kiyotomo Ichiki

In 2000, Giorgi Dvali, Gregory Gabadadze and Massimo Porrati (Dvali et al. 2000) was proposed a new braneworld model named as DGP model, having two branches with $(\epsilon=+1)$ and $(\epsilon=-1)$. Former one $(~\epsilon=+1)$ known as the…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Mahasweta Biswas , Shounak Ghosh , Ujjal Debnath

For a perfect fluid, pressure $p$ and energy density $\rho$ are related via the equation of state (EOS) $\omega = p/\rho$, where $\omega$ is the EOS parameter, being its interpretation usually constrained to a numerical value for each…

General Relativity and Quantum Cosmology · Physics 2024-09-27 Lucas Squillante , Gabriel O. Gomes , Isys F. Mello , Guilherme Nogueira , Antonio C. Seridonio , Roberto E. Lagos-Monaco , Mariano de Souza