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Related papers: Cosmography in $f(Q)$ gravity

200 papers

In order to account for the observable Universe, any comprehensive theory or model of cosmology must draw from many disciplines of physics, including gauge theories of strong and weak interactions, the hydrodynamics and microphysics of…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Peter Anninos

Advances in our understanding of the origin, evolution and structure of the universe have long been driven by cosmological perturbation theory, model building and effective field theory. In this review, we introduce numerical relativity as…

General Relativity and Quantum Cosmology · Physics 2022-03-08 Anna Ijjas

Cosmic spatial curvature is a fundamental geometric quantity of the Universe. We investigate a model independent, geometric approach to measure spatial curvature directly from observations, without any derivatives of data. This employs…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-01 Mikhail Denissenya , Eric V. Linder , Arman Shafieloo

A cubic correction of $f(T)$ gravity, where $T$ is the teleparallel scalar torsion, is considered to describe gravity in spatially flat Friedmann-Robertson-Walker model. A scale factor permitting departure from inflation era has been…

General Physics · Physics 2015-11-06 G. G. L. Nashed , W. El Hanafy

$f(Q,T)$ theory of gravity is very recently proposed to incorporate within the action Lagrangian, the trace $T$ of the energy-momentum tensor along with the non-metricity scalar $Q$. The cosmological application of this theory in a…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Tee-How Loo , M. Koussour , Avik De

We extract constraints on the transition redshift $z_{tr}$, determining the onset of cosmic acceleration, predicted by an effective cosmographic construction, in the framework of $f(T)$ gravity. In particular, employing cosmography we…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Salvatore Capozziello , Orlando Luongo , Emmanuel N. Saridakis

We investigate the cosmological implications of $f(Q)$ gravity, which is a modified theory of gravity based on non-metricity, in non-flat geometry. We perform a detailed dynamical-system analysis keeping the $f(Q)$ function completely…

General Relativity and Quantum Cosmology · Physics 2023-06-26 Hamid Shabani , Avik De , Tee-How Loo , Emmanuel N. Saridakis

The paper deals with cosmology in modified f(T) gravity theory. With some phenomenological choices for the function f(T) it is possible to have cosmological solutions describing different phases of the evolution of the Universe for the…

General Relativity and Quantum Cosmology · Physics 2020-11-03 Akash Bose , Subenoy Chakraborty

Numerical N-body simulations of large scale structure formation in the universe are based on Newtonian gravity. However, according to our current understanding, the most correct theory of gravity is general relativity. It is therefore…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-27 Ugo Bertello

We consider multidimensional gravity with a Lagrangian containing the Ricci tensor squared and the Kretschmann invariant. In a Kaluza-Klein approach with a single compact extra space of arbitrary dimension, with the aid of a slow-change…

General Relativity and Quantum Cosmology · Physics 2009-11-13 K. A. Bronnikov , S. A. Kononogov , V. N. Melnikov , S. G. Rubin

A cosmological model is formulated in the context of a scalar-tensor theory of gravity in which the entire cosmic background evolution is due to a complex scalar field evolving in Minkowski spacetime, such that its (dimensional) modulus is…

General Physics · Physics 2019-09-24 Meir Shimon

Cosmic voids are low-mass-density regions on intergalactic scales. They are where cosmic expansion and acceleration are most dominant, important places to understand and analyze for cosmology. This entry summarises theoretical underpinnings…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-01 Yan-Chuan Cai , Mark Neyrinck

The cosmology of general fourth order corrections to Einstein gravity is considered, both for a homogeneous and isotropic background and for general tensor perturbations. It is explicitly shown how the standard cosmological history can be…

General Relativity and Quantum Cosmology · Physics 2011-03-07 William Nelson

Our modified gravity theory (MOG) is a gravitational theory without exotic dark matter, based on an action principle. MOG has been used successfully to model astrophysical phenomena such as galaxy rotation curves, galaxy cluster masses, and…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 J. W. Moffat , V. T. Toth

We constrain the parameters describing the kinematical state of the universe using a cosmographic approach, which is fundamental in that it requires a very minimal set of assumptions (namely to specify a metric) and does not rely on the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Vincenzo Vitagliano , Jun-Qing Xia , Stefano Liberati , Matteo Viel

As revealed by Hubble in 1928, our Universe is expanding. This discovery was fundamental to widening our horizons and our conception of space, and since then determining the rate at which our Universe is expanding has become one of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-04 Michele Moresco

Modified gravity theories can be used for the description of homogeneous and isotropic cosmological models through the corresponding field equations. These can be cast into systems of autonomous differential equations because of their sole…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

In this work we use cosmography to alleviate the degeneracy among cosmological models, proposing a way to parameterize matter and dark energy in terms of cosmokinematics quantities. The recipe of using cosmography allows to expand…

General Relativity and Quantum Cosmology · Physics 2015-12-23 Orlando Luongo , Giovanni Battista Pisani , Antonio Troisi

Using a new sub-sample of observed strong gravitational lens systems, for the first time, we present the equation for the angular diameter distance in the $y$-redshift scenario for cosmography and use it to test the cosmographic parameters.…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-08 Andrés Lizardo , Mario H. Amante , Miguel A. García-Aspeitia , Juan Magaña , V. Motta

Among the various possibilities to probe the theory behind the recent accelerated expansion of the universe, the energy conditions (ECs) are of particular interest, since it is possible to confront and constrain the many models, including…

General Relativity and Quantum Cosmology · Physics 2018-09-17 M. E. S. Alves , F. C. Carvalho , J. C. N. de Araujo , M. Penna-Lima , S. D. P. Vitenti
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