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Related papers: Testing gravity with CAMB and CosmoMC

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We investigate a modified cosmological model aimed at addressing the Hubble tension, considering revised dynamics in the late Universe. The model introduces a parameter $c$ affecting the evolution equations, motivated by a modified Poisson…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-13 Luis A. Escamilla , Donatella Fiorucci , Giovanni Montani , Eleonora Di Valentino

A fundamental element of scale-dependent gravity is the scale-setting procedure. We present a new covariant expression to set the scale that arises when examining the field equations. Considering the renormalization group equations and…

General Relativity and Quantum Cosmology · Physics 2025-04-28 Nicolas R. Bertini

We present $\texttt{MG-evolution}$, an $N$-body code simulating the cosmological structure formation for parametrised modifications of gravity. It is built from the combination of parametrised linear theory with a parametrisation of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-03 Farbod Hassani , Lucas Lombriser

Gravitation governs the expansion and fate of the universe, and the growth of large scale structure within it, but has not been tested in detail on these cosmic scales. The observed acceleration of the expansion may provide signs of…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-29 Eric V. Linder

All quantum gravity approaches lead to small modifications in the standard laws of physics which lead to violations of Lorentz invariance. One particular example is the extended standard model (SME). Here, a general phenomenological…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Claus Laemmerzahl , Alfredo Macias , Holger Mueller

First, we establish which measures of large-scale perturbations are least afflicted by gauge artifacts and directly map the apparent evolution of inhomogeneities to local interactions of cosmological species. Considering nonlinear and…

Astrophysics · Physics 2007-05-23 Sergei Bashinsky

In this work, we perform observational data analysis on Einsteinian cubic gravity and $f(P)$ gravity to constrain the parameter space of the theories. We use the 30-point $z-H(z)$ cosmic chronometer data as the observational tool for our…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-14 Kinsuk Giri , Prabir Rudra

In this paper, we have explored the field equations of f(T, B) gravity as an extension of teleparallel gravity in an isotropic and homogeneous space time. In the basic formalism developed, the dynamical parameters are derived by…

General Relativity and Quantum Cosmology · Physics 2024-09-27 S. A. Kadam , Jackson Levi Said , B. Mishra

We present measurements of both scale- and time-dependent deviations from the standard gravitational field equations. These late-time modifications are introduced separately for relativistic and non-relativistic particles, by way of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-16 Andrew Johnson , Chris Blake , Jason Dossett , Jun Koda , David Parkinson , Shahab Joudaki

Recent conjectures that there are mesoscopically ``large'' extra dimensions, through which gravity propagates have interesting implications for much of physics. The scenario implies gross departures from Newton's law of gravity at small…

Astrophysics · Physics 2009-11-07 Steinn Sigurdsson

Modified gravity theories are a popular alternative to dark energy as a possible explanation for the observed accelerating cosmic expansion, and their cosmological tests are currently an active research field. Studies in recent years have…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Juan J. Ceron-Hurtado , Jian-hua He , Baojiu Li

In this review we present a thoroughly comprehensive survey of recent work on modified theories of gravity and their cosmological consequences. Amongst other things, we cover General Relativity, Scalar-Tensor, Einstein-Aether, and Bimetric…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Timothy Clifton , Pedro G. Ferreira , Antonio Padilla , Constantinos Skordis

We introduce a cosmological model in the framework of Generalised Massive Gravity. This theory is an extension of non-linear massive gravity with a broken translation symmetry in the St\"uckelberg space. In a recent work, we showed the…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Michael Kenna-Allison , A. Emir Gumrukcuoglu , Kazuya Koyama

Noncommutative geometry can provide effective description of physics at very short distances taking into account generic effects of quantum gravity. Inflation amplifies tiny quantum fluctuations in the early universe to macroscopic scales…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Tomi S. Koivisto , David F. Mota

In standard general relativity the universe cannot be started with arbitrary initial conditions, because four of the ten components of the Einstein's field equations (EFE) are constraints on initial conditions. In the previous work it was…

General Relativity and Quantum Cosmology · Physics 2017-11-08 Tomonori Totani

We construct a consistency test of General Relativity (GR) on cosmological scales. This test enables us to distinguish between the two alternatives to explain the late-time accelerated expansion of the universe, that is, dark energy models…

Astrophysics · Physics 2009-06-23 Yong-Seon Song , Kazuya Koyama

A new gauge-invariant approach for describing cosmological perturbations is developed. It is based on a physically motivated splitting of the stress-energy tensor of the perturbation into two parts - the bare perturbation and the…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Sergei M. Kopeikin , Juan Ramirez , Bahram Mashhoon , Mikhail V. Sazhin

Modifying the Einstein's gravity at large distance scales is one of the interesting proposals to explain the late time acceleration of the universe. In this paper, we analyse scaling solutions in modified gravity models where the universe…

Astrophysics · Physics 2009-06-23 A. A Sen , N. Chandrachani Devi

One of the challenges in testing gravity with cosmology is the vast freedom opened when extending General Relativity. For linear perturbations, one solution consists in using the Effective Field Theory of Dark Energy (EFT of DE). Even then,…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Jérôme Gleyzes

Using the covariant approach and conformal transformations, we present a gauge-invariant formalism for cosmological perturbations in generalized Einstein theories (GETs), including the Brans-Dicke theory, theories with a non-minimally…

Astrophysics · Physics 2010-11-01 Toshinari Hirai , Kei-ichi Maeda
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