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The Cardassian universe is a proposed modification to the Friedmann Robertson Walker (FRW) equation in which the universe is flat, matter dominated, and accelerating. Here we generalize the original Cardassian proposal to include additional…

High Energy Physics - Phenomenology · Physics 2010-12-09 Katherine Freese

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

It is shown that cosmological equations for homogeneous isotropic models deduced in the framework of the Poincar\'e gauge theory of gravity by certain restrictions on indefinite parameters of gravitational Lagrangian take at asymptotics the…

General Relativity and Quantum Cosmology · Physics 2009-09-29 A. V. Minkevich

We show that inflation and current cosmic acceleration can be generated by a metric-affine f(R) gravity formulated in the Einstein conformal frame, if the gravitational Lagrangian L(R) contains both positive and negative powers of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Nikodem J. Poplawski

We use recent measurements of the expansion history of the universe to place constraints on the parameter space of cubic Galileon models, in particular we concentrate on those models which contain the simplest Galileon term plus a linear…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-20 Emilio Bellini , Raul Jimenez

The current standard model of cosmology, the LambdaCDM model, is based on the homogeneous FLRW solutions of the Einstein equations to which some perturbations are added to account for the CMB features and structure formation at large…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-14 Marie-Noëlle Célérier

We study the late-time cosmological expansion of a modified teleparallel gravity model of type logarithmic type. This modified gravitational lagrangian yields a cosmological constant term and also power-law corrections to the teleparallel…

General Relativity and Quantum Cosmology · Physics 2025-10-27 Adriel O. Aquino , Euclides G. Silva

In this article we propose to add stress-energy tensor to the Einstein equations, assuming that the matter-energy and the metric space-time is nothing but a continuous medium with some elastic properties. We first give a general expression…

General Relativity and Quantum Cosmology · Physics 2014-09-29 Mathieu Beau

Modified gravity has attracted much attention over the last few years and remains a potential candidate for dark energy. In particular, the so-called viable f(R) gravity theories, which are able to both recover General Relativity (GR) and…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby , Sulona Kandhai , Diego Saez-Gomez

We study the late-time cosmological dynamics of a spatially flat FLRW universe in the framework of $f(Q)$ gravity, where $Q$ denotes the nonmetricity scalar. The matter sector is modeled as a bulk viscous fluid with a free equation-of-state…

General Relativity and Quantum Cosmology · Physics 2026-02-20 Simran Arora , Sai Swagat Mishra , P. K. Sahoo

In this communication, we consider a wide class of extensions to General Relativity that break explicitly the Einstein Equivalence Principle by introducing a multiplicative coupling between a scalar field and the electromagnetic Lagrangian.…

General Relativity and Quantum Cosmology · Physics 2015-05-06 A. Hees , O. Minazzoli , J. Larena

We construct cosmological model in nonmetricity scalar functional gravitational Lagrangian $f(Q)$ which describes the dynamical evolution of the late accelerating universe. Cosmological models are constructed considering different…

General Relativity and Quantum Cosmology · Physics 2025-04-23 Bikash Chandra Roy , Aroonkumar Beesham , Bikash Chandra Paul

In this paper, we study a cosmological model in general relativity within the framework of spatially flat Friedmann-Robertson-Walker space-time filled with ordinary matter (baryonic), radiation, dark matter and dark energy, where the latter…

General Relativity and Quantum Cosmology · Physics 2014-09-04 Suresh Kumar , Lixin Xu

Symmetric teleparallel gravity and its $f(Q)$ extensions have emerged as promising alternatives to General Relativity (GR), yet the role of explicit geometry-matter couplings remains largely unexplored. In this work, we address this gap by…

General Relativity and Quantum Cosmology · Physics 2025-09-22 Ayush Hazarika , Simran Arora , P. K. Sahoo , Tiberiu Harko

A wealth of astronomical data indicate the presence of mass discrepancies in the Universe. The motions observed in a variety of classes of extragalactic systems exceed what can be explained by the mass visible in stars and gas. Either (i)…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-28 Benoit Famaey , Stacy McGaugh

In recent years, modifications to General Relativity (GR) have been explored to address cosmological observations, particularly in the context of late-time cosmic acceleration. Among these, modifications based on the Teleparallel Equivalent…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

Major observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark energy that cannot be represented solely…

Astrophysics · Physics 2009-03-12 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

We consider f(R,T) modified theory of gravity in which, in general, the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor. We indicate that in this type of the theory,…

General Relativity and Quantum Cosmology · Physics 2016-10-05 Raziyeh Zaregonbadi , Mehrdad Farhoudi

Constraints on the Covariant Canonical Gauge Gravity (CCGG) theory from low-redshift cosmology are studied. The formulation extends Einstein's theory of General Relativity (GR) by a quadratic Riemann-Cartan term in the Lagrangian,…

General Relativity and Quantum Cosmology · Physics 2021-02-09 David Benisty , David Vasak , Johannes Kirsch , Jurgen Struckmeier

We investigate the new observational constraints on $f(T)$ gravity that arise from the effects of primordial gravitational waves (GWs) on the cosmic microwave background (CMB) anisotropies and the BB spectrum. We first show that on the GWs…

General Relativity and Quantum Cosmology · Physics 2018-11-30 Rafael C. Nunes , Supriya Pan , Emmanuel N. Saridakis
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