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Related papers: Cosmic voids in modified gravity scenarios

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Within the effective field theory approach to cosmic acceleration, the background expansion can be specified separately from the gravitational modifications. We explore the impact of modified gravity in a background different from a…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Guilherme Brando , Felipe T. Falciano , Eric V. Linder , Hermano E. S. Velten

The missing gravity in galaxies requires dark matter, or alternatively a modification of gravity or inertia. These theoretical possibilities of fundamental importance may be distinguished by the statistical relation between the observed…

Astrophysics of Galaxies · Physics 2022-12-21 Kyu-Hyun Chae

A large fraction of cosmological information on dark energy and gravity is encoded in the nonlinear regime. Precision cosmology thus requires precision modeling of nonlinearities in general dark energy and modified gravity models. We modify…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Weiguang Cui , Pengjie Zhang , Xiaohu Yang

We study cosmology in a class of minimally modified gravity (MMG) with two local gravitational degrees of freedom. We classify modified gravity theories into type-I and type-II: theories of type-I have an Einstein frame and can be recast by…

General Relativity and Quantum Cosmology · Physics 2019-01-16 Katsuki Aoki , Antonio De Felice , Chunshan Lin , Shinji Mukohyama , Michele Oliosi

In 'modified' gravity the observed acceleration of the universe is explained by changing the gravitational force law or the number of degrees of freedom in the gravitational sector. Both possibilities can be tested by measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Clare Burrage , David Parkinson , David Seery

One of the most pressing issues in cosmology is whether general relativity (GR) plus a dark sector is the underlying physical theory or whether a modified gravity model is needed. Upcoming dark energy experiments designed to probe dark…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Charles Shapiro , Scott Dodelson , Ben Hoyle , Lado Samushia , Brenna Flaugher

Modified gravity theories may provide an alternative to dark energy to explain cosmic acceleration. We argue that the observational program developed to test dark energy needs to be augmented to capture new tests of gravity on astrophysical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Bhuvnesh Jain

A modified Mimetic gravity (MMG) is proposed as a generalization of general relativity. The model contain a physical metric which is function of an auxiliary (unphysical) metric and a Lyra's metric. We construct different kinds of…

General Relativity and Quantum Cosmology · Physics 2015-04-07 Davood Momeni , Aziza Altaibayeva , Ratbay Myrzakulov

Dynamical mass discrepancies in galaxies have two possible explanations: the existence of large amounts of dark matter or the breakdown of Newtonian gravity. True dark matter halos of galaxies could differ in several respects from apparent…

Astrophysics · Physics 2007-05-23 J. A. Sellwood , A. Kosowsky

We consider the cosmological consequences of a special scalar-tensor-vector theory of gravity, known as MOG (for MOdified Gravity), proposed to address the dark matter problem. This theory introduces two scalar fields $G(x)$ and $\mu(x)$,…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Sara Jamali , Mahmood Roshan , Luca Amendola

Cosmic voids, the less dense patches of the Universe, are promising laboratories to extract cosmological information. Thanks to their unique low density character, voids are extremely sensitive to diffuse components such as neutrinos and…

Modifications to gravity can provide attractive alternatives to the dark components of the standard model of cosmology. These modifications to general relativity (GR) must be hidden at small scales where theory is well tested, and so one…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-06 Benjamin Bose

We use properties of void populations identified in $N$-body simulations to forecast the ability of upcoming galaxy surveys to differentiate models of f(R) gravity from \lcdm~cosmology. We analyze multiple simulation realizations, which…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Paul Zivick , P. M. Sutter , Benjamin D. Wandelt , Baojiu Li , Tsz Yan Lam

We review recent developments and results in testing general relativity (GR) at cosmological scales. The subject has witnessed rapid growth during the last two decades with the aim of addressing the question of cosmic acceleration and the…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-09 Mustapha Ishak

Testing gravity and the concordance model of cosmology, $\Lambda$CDM, at large scales is a key goal of this decade's largest galaxy surveys. Here we present a comparative study of dark matter power spectrum predictions from different…

The general theory of relativity (GR) was proposed with an aim of incorporating Mach's principle mathematically. Despite early hopes, it became evident that GR did not follow Mach's principle. Over time, multiple researchers attempted to…

General Relativity and Quantum Cosmology · Physics 2025-09-09 Santanu Das

We review various modified gravities considered as gravitational alternative for dark energy. Specifically, we consider the versions of $f(R)$, $f(G)$ or $f(R,G)$ gravity, model with non-linear gravitational coupling or string-inspired…

High Energy Physics - Theory · Physics 2009-09-17 S. Nojiri , S. D. Odintsov

An obvious criterion to classify theories of modified gravity is to identify their gravitational degrees of freedom and their coupling to the metric and the matter sector. Using this simple idea, we show that any theory which depends on the…

General Relativity and Quantum Cosmology · Physics 2017-03-01 Xavier Calmet , Iberê Kuntz

We investigate the cosmological perturbations in the context of a Scalar-Tensor-Vector theory of Gravity known as MOG in the literature. Recent investigations show that MOG reproduces a viable background cosmological evolution comparable to…

General Relativity and Quantum Cosmology · Physics 2020-02-18 Sara Jamali , Mahmood Roshan , Luca Amendola

In the past decade or so observations of supernovae, Large Scale Structures (LSS), and the Cosmic Microwave Background (CMB) have confirmed the presence of what is called dark energy - the cause of accelerating expansion of the Universe.…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-14 Houri Ziaeepour
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