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We consider f(Q) extended symmetric teleparallel cosmologies, where Q is the non-metricity scalar, and constrain its functional form through the order reduction method. By using this technique, we are able to reduce and integrate the field…

General Relativity and Quantum Cosmology · Physics 2020-12-03 Francesco Bajardi , Daniele Vernieri , Salvatore Capozziello

We consider homogeneous and isotropic cosmological models in the framework of three geometrical theories of gravitation: in the Einstein general relativity they are given in terms of the curvature of the Levi-Civita connection in torsion…

General Relativity and Quantum Cosmology · Physics 2023-12-20 Laur Järv , Piret Kuusk

We discuss the cosmological consequences of an interacting model in the dark sector in which the $\Lambda$ component evolves as a truncated power series of the Hubble parameter. In order to constrain the free parameters of the model we…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-10 F. E. M. Costa , J. A. S. Lima , F. A. Oliveira

We make a perturbative analysis of the number of degrees of freedom in a large class of metric theories respecting spatial symmetries, of which the Lagrangian includes kinetic terms of both the spatial metric and the lapse function. We show…

General Relativity and Quantum Cosmology · Physics 2019-05-13 Xian Gao , Chao Kang , Zhi-Bang Yao

Cosmological structures grow differently in theories of gravity which are modified as compared to Einstein's General relativity (GR). Cosmic microwave background (CMB) fluctuation patterns at the last scattering surface are lensed by these…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 Toshiya Namikawa , François R. Bouchet , Atsushi Taruya

We investigate the impact on cosmological observables of $f(Q)$-gravity, a specific class of modified gravity models in which gravity is described by the non-metricity scalar, $Q$. In particular we focus on a specific model which is…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 Noemi Frusciante

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

Teleparallel gravity offers a path to resolve a number of longstanding issues in general relativity by re-interpreting gravitation as an artifact of torsion rather than curvature. The present work deals with cosmological solutions in an…

General Relativity and Quantum Cosmology · Physics 2019-06-04 Soumya Chakrabarti , Jackson Levi Said , Kazuharu Bamba

The general relativistic non--linear dynamics of a self--gravitating collisionless fluid with vanishing vorticity is studied in synchronous and comoving -- i.e. {\em Lagrangian} -- coordinates. Writing the equations in terms of the metric…

Astrophysics · Physics 2007-05-23 Sabino Matarrese

This paper proposes a systematic study of cosmological signatures of modifications of gravity via the presence of a scalar field with a multiplicative coupling to the electromagnetic Lagrangian. We show that, in this framework, variations…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-27 A. Hees , O. Minazzoli , J. Larena

This work examines the cosmological implications of two functional forms of $f(R,T) = R + \alpha T^n$ gravity: for two different value of $n $ where $n=1$ and $n\neq 1$, and $\alpha$ and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-24 Mustapha Lamaaoune

In this paper we use the conformal teleparallel gravity to study an isotropic and homogeneous Universe which is settled by the FRW metric. We solve the field equations and we obtain the behavior of some cosmological parameters such as scale…

General Relativity and Quantum Cosmology · Physics 2016-03-30 J. G. Silva , A. F. Santos , S. C. Ulhoa

Symmetric teleparallel gravity (STG) is an alternative description of the gravitational field as an effect of the nonmetricity rather than the curvature of the spacetime. For an specific choice of the symmetric teleparallel lagrangian, the…

General Relativity and Quantum Cosmology · Physics 2022-12-15 J. E. G. Silva

We conduct a Markov Chain Monte Carlo study of the Dvali-Gabadadze-Porrati (DGP) self-accelerating braneworld scenario given the cosmic microwave background (CMB) anisotropy, supernovae and Hubble constant data by implementing an effective…

Astrophysics · Physics 2010-04-21 Wenjuan Fang , Sheng Wang , Wayne Hu , Zoltan Haiman , Lam Hui , Morgan May

According to the separate universe conjecture, spherically symmetric sub-regions in an isotropic universe behave like mini-universes with their own cosmological parameters. This is an excellent approximation in both Newtonian and general…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-14 Gábor Rácz , László Dobos , Róbert Beck , István Szapudi , István Csabai

In this paper, we study the constraints on the $f(Q)=Q/(8\pi G) - \alpha \ln(Q/Q_0)$, symmetric teleparallel model using local measurements and gravitational wave mock standard sirens. Using observational local SNIa and BAO data and energy…

General Relativity and Quantum Cosmology · Physics 2023-08-14 José Antonio Nájera , Carlos Aráoz Alvarado , Celia Escamilla-Rivera

We analyze inhomogeneous cosmological models in the local Universe, described by the Lema\^itre-Tolman-Bondi (LTB) metric and developed using linear perturbation theory on a homogeneous and isotropic Universe background. Focusing on the…

General Relativity and Quantum Cosmology · Physics 2024-05-16 Tiziano Schiavone , Giovanni Montani

We provide a cosmological test of modified gravity with two tensorial degrees of freedom and no extra propagating scalar mode. The theory of gravity we consider admits a cosmological model that is indistinguishable from the $\Lambda$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-01 Takashi Hiramatsu , Tsutomu Kobayashi

We consider the possibility of probing left-right symmetric model (LRSM) via cosmic microwave background (CMB). We adopt the minimal LRSM with Higgs doublets, also known as the doublet left-right model (DLRM), where all fermions including…

High Energy Physics - Phenomenology · Physics 2020-09-02 Debasish Borah , Arnab Dasgupta , Chayan Majumdar , Dibyendu Nanda

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
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