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In this paper, we explore the particle creation scenario in the context of $f(\mathcal{G})$ gravity in flat-FLRW metric. For this purpose, from the perspective of thermodynamics and considering an adiabatic universe, we obtain the modified…

General Relativity and Quantum Cosmology · Physics 2025-05-30 S. Ganjizadeh , Alireza Amani , M. A. Ramzanpour

The cosmological implications of the Covariant Canonical Gauge Theory of Gravity (CCGG) are investigated. We deduce that, in a metric compatible geometry, the requirement of covariant conservation of matter invokes torsion of space-time. In…

General Relativity and Quantum Cosmology · Physics 2024-10-28 David Vasak , Johannes Kirsch , Juergen Struckmeier

A new phenomenological dark energy model, originally associated to the large-scale structure formation and considered as a solution to the fine-tuning and coincidence problems related to the cosmological constant, was analyzed within the…

General Relativity and Quantum Cosmology · Physics 2026-03-05 A. Kazım Çamlıbel

The acceleration of the universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark…

Astrophysics · Physics 2008-11-26 Edmund Bertschinger , Phillip Zukin

Dark energy cosmology is considered in a modified Gauss-Bonnet (GB) model of gravity where an arbitrary function of the GB invariant, $f(G)$, is added to the General Relativity action. We show that such theory is endowed with a quite rich…

High Energy Physics - Theory · Physics 2008-11-26 Guido Cognola , Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov , Sergio Zerbini

In this work we apply the gravity-thermodynamics approach for the case of generalized mass-to-horizon entropy, which is a two-parameter extension of Bekenstein-Hawking entropy that arises from the extended mass-to-horizon relation, that is…

General Relativity and Quantum Cosmology · Physics 2025-04-01 Spyros Basilakos , Andreas Lymperis , Maria Petronikolou , Emmanuel N. Saridakis

We investigate the evolution of cosmological perturbations in models of dark energy described by a time-like unit normalized vector field specified by a general function $\mathcal{F}(\mathcal{K})$, so-called Generalized Einstein-Aether…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Richard A. Battye , Francesco Pace , Damien Trinh

The present work deals with scalar field cosmology in the framework of a quantum gravity modified Einstein-Hilbert Lagrangian with variable $G$ and $\Lambda$. Using Renormalization group, variable $G$ behaves as a minimally coupled filed…

General Relativity and Quantum Cosmology · Physics 2019-11-22 Santu Mondal , Sourav Dutta , Subenoy Chakraborty

This paper aims to develop non-interacting ghost dark energy and generalized ghost dark energy models within the framework of $f(Q)$ theory using the correspondence scheme. We use pressureless matter and a power-law scale factor. The cosmic…

General Relativity and Quantum Cosmology · Physics 2025-07-04 M. Sharif , Madiha Ajmal

The goal of this paper is to study new cosmological models where the dark energy is a varying Chaplygin gas. This specific dark energy model with non-linear EoS had been often discussed in modern cosmology. Contrary to previous studies, we…

General Relativity and Quantum Cosmology · Physics 2021-05-04 M. Khurshudyan , R. Myrzakulov

The starting point in this note is $f(R)$ modified gravity in a cosmological setting. We assume a spatially flat Universe to describe late-time cosmology and the perfect-fluid equation of state $p=\omega\rho$ to model the hypothesized dark…

General Relativity and Quantum Cosmology · Physics 2017-06-13 Peter K. F. Kuhfittig

We generalize the cosmic energy equation to the case when massive particles interact via a modified gravitational potential of the form phi(a, r), which is allowed to explicitly depend upon the cosmological time through the expansion factor…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 Yuri Shtanov , Varun Sahni

In this work, we investigate the cosmological dynamics of a spatially flat Friedmann--Lema\^itre--Robertson--Walker Universe in the framework of generalized \( \mathcal{F}(\mathcal{R},\Sigma,\mathcal{T}) \) gravity by incorporating…

General Relativity and Quantum Cosmology · Physics 2026-05-15 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , M. Zeyauddin

We propose a matter effect for the gravitational ultraviolet/infrared (UV/IR) mixing solution to the cosmological constant problem. Previously, the gravitational UV/IR mixing model implied a non-standard equation of state for dark energy,…

High Energy Physics - Theory · Physics 2020-04-15 Joseph Bramante , Elizabeth Gould

In this work, we investigate Newtonian cosmologies with a time-varying gravitational constant, $G(t)$. We examine whether such models can reproduce the low-redshift cosmological observations without a cosmological constant, or any other…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-01 Ekim Taylan Hanımeli , Isaac Tutusaus , Brahim Lamine , Alain Blanchard

We use astrophysical data to shed light on fundamental physics by constraining parametrized theoretical cosmological and gravitational models. Gravitational parameters are those constants that parametrize possible departures from Einstein's…

Astrophysics · Physics 2008-08-18 Yi Mao

We investigate the cosmological implications of a new class of modified gravity, where the field equations generically include higher-order derivatives of the matter fields, arising from the introduction of non-dynamical auxiliary fields in…

General Relativity and Quantum Cosmology · Physics 2016-07-01 Tiberiu Harko , Francisco S. N. Lobo , Emmanuel N. Saridakis

We examine the effects of possible phenomenological interactions between dark energy and dark matter on cosmological parameters and their efficiency in solving the coincidence problem. We work with two simple parameterizations of the…

Astrophysics · Physics 2009-06-23 Jian-Hua He , Bin Wang

From the equivalence principle (EP) and experiments on gravitational (G) time dilation (GTD) it is proved that the standards of observers located in different ``distances'' from the earth are physically different with respect to each other.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Rafael A. Vera

On going good number of research works establish Modified Chaplygin Gas as one one of the most favoured candidates of Dark Energy. In our present work, new bound on the parameter space of associated model - parameter has been worked out…

General Physics · Physics 2010-06-09 Balendra Kr. Dev Choudhury , Julie Saikia
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