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In this paper, we study the $F(R, G)$ gravity model with an interacting model by flat-FRW metric in a viscous fluid. We consider that the universe dominates with components of dark matter and dark energy. This means that the dark matter…

General Relativity and Quantum Cosmology · Physics 2023-03-22 E. Mahichi , Alireza Amani , M. A. Ramzanpour

Astronomical measurements of the Omegas for mass density, cosmological constant lambda and curvature k are shown to be sufficient to produce a unique and detailed cosmological model describing dark energy influences based on the Friedman…

General Physics · Physics 2010-01-14 James G. Gilson

It has been shown beyond reasonable doubt that the majority (about 95%) of the total energy budget of the universe is given by the dark components, namely Dark Matter and Dark Energy. What constitutes these components remains to be…

General Relativity and Quantum Cosmology · Physics 2021-02-08 Saurya Das , Mohit Kumar Sharma , Sourav Sur

The Friedmann equation, augmented with an additional term that effectively takes on the role of dark energy, is demonstrated to be an exact solution to the recently proposed gravitational theory named "conformal Killing gravity." This…

General Relativity and Quantum Cosmology · Physics 2023-11-20 Junpei Harada

A phenomenological approach is proposed to the problem of universe accelerated expansion and of the dark energy nature. A general class of models is introduced whose energy density depends on the redshift $z$ in such a way that a smooth…

Astrophysics · Physics 2009-11-10 V. F. Cardone , A. Troisi , S. Capozziello

Following the approach of the induced-matter theory, we investigate the cosmological implications of a five-dimensional Brans-Dicke theory, and propose to explain the acceleration of the universe. After inducing in a four-dimensional…

General Relativity and Quantum Cosmology · Physics 2013-07-10 Amir F. Bahrehbakhsh , Mehrdad Farhoudi , Hajar Vakili

A dark Friedman-Robertson-Walker fluid governed by a non-linear inhomogeneous equation of state is considered which can be viewed as a conveniently simple paradigm for a whole class of models which exhibit phase transitions from a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 I. Brevik , E. Elizalde , O. Gorbunova , A. V. Timoshkin

In this paper, we investigate the behavior of equation of state parameter and energy density for dark energy in the framework of f(T) gravity. For this purpose, we use anisotropic LRS Bianchi type I universe model. The behavior of…

General Relativity and Quantum Cosmology · Physics 2015-06-15 M. Sharif , Sehrish Azeem

We consider the holographic dark energy model with axial torsion which satisfy the cosmological principle. Subsequently, by using the torsional analogues of Friedmann equations for the new equation from Einstein-Cartan gravity theory, we…

General Relativity and Quantum Cosmology · Physics 2025-11-18 Yongjun Yun , Jungjai Lee

We present a comprehensive phase-space analysis of a quadratic dark energy model where the pressure includes a nonlinear term proportional to the square of the energy density. This minimal extension beyond the $\Lambda$CDM framework…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Sahar Mohammadi , Ebrahim Yusofi , Kosar Asadi

We study the dynamical aspects of dark energy in the context of a non-minimally coupled scalar field with curvature and torsion. Whereas the scalar field acts as the source of the trace mode of torsion, a suitable constraint on the torsion…

General Relativity and Quantum Cosmology · Physics 2017-08-18 Sourav Sur , Arshdeep Singh Bhatia

It is shown that so-called dark energy could possible be a manifestation of the gravitational vortex producing the "gravitomagnetic" (GM) force field: associated with cosmic matter rotation and inertial spacetime frame dragging. The general…

General Physics · Physics 2018-01-24 Reva Kay Williams

We discuss a model of the universe where dark energy is replaced by electrically-charged extremely-massive dark matter. The cosmological constant has a value of the same order as the mean matter density, consistent with observations, and is…

General Physics · Physics 2026-01-26 Paul H. Frampton

A late accelerated expansion of the Universe is obtained from non-relativistic particles with a short-range attractive interaction, and low enough temperature to produce a Bose-Einstein condensate; by considering coupled dark-energy…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-13 Jaime Besprosvany , German Izquierdo

It has recently been shown that the observed Hubble function for cosmological expansion can be fitted accurately back to redshift unity (7.33 Gyr ago) with only one free constant, while neglecting cosmic curvature and mass, using the…

General Physics · Physics 2021-05-26 R. K. Nesbet

Measurement of accelerated expansion in the Universe led to propose a new cosmic fluid as its cause: dark energy. Its various incarnations offer a wealth of models whose relevance it is important to discriminate via contacts with…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Morgan Le Delliou

Specific internal self-interactions in gaseous cosmic fluids are shown to give rise to effective negative pressures which may violate the strong energy condition. On this basis we discuss the transition from an initial de Sitter phase to a…

Astrophysics · Physics 2016-08-16 W. Zimdahl , A. B. Balakin , D. J. Schwarz , D. Pavón

In this work we present the cosmological dynamics of interacting dark energy models in the framework of particle creation mechanism. The particle creation mechanism presented here describes the true non equilibrium thermodynamics of the…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Sujay Kr. Biswas , Wompherdeiki Khyllep , Jibitesh Dutta , Subenoy Chakraborty

Motivated by an earlier work on fractional-action cosmology with a periodic weight function [1], we extend it by choosing a power-law weight function in the action. In this approach, we obtain a varying gravitational coupling constant. We…

General Physics · Physics 2012-03-16 Mubasher Jamil , Muneer A. Rashid , D. Momeni , O. Razina , Kuralay Esmakhanova

A six parameter cosmological model, involving a vacuum energy density that is extremely tiny compared to fundamental particle physics scales, describes a large body of increasingly accurate astronomical data. In a first part of this brief…

High Energy Physics - Phenomenology · Physics 2009-11-11 Norbert Straumann