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Related papers: Distinguishing modified gravity models

200 papers

The recent observational data in cosmology seem to indicate that the universe is currently expanding in an accelerated way. An intriguing interpretation of these data is that they may just be signalling that Einstein's General Relativity is…

High Energy Physics - Theory · Physics 2018-05-18 Fulvio Sbisà

The statistics of dark matter halos is an essential component of understanding the nonlinear evolution in modified gravity cosmology. Based on a series of modified gravity N-body simulations, we investigate the halo mass function,…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-21 Youcai Zhang , Pengjie Zhang , Xiaohu Yang , Weiguang Cui

This study conducts a meticulous examination of the cosmological implications inherent in Rastall gravity and $f(R)$ gravity models, assessing their efficacy across distinct cosmic epochs, from early universe structure formation to…

General Relativity and Quantum Cosmology · Physics 2025-01-14 Muhammad Yarahmadi , Amin Salehi , Hadis Mousavi

We carry out a suite of cosmological simulations of modified action f(R) models where cosmic acceleration arises from an alteration of gravity instead of dark energy. These models introduce an extra scalar degree of freedom which enhances…

Astrophysics · Physics 2008-12-30 Hiroaki Oyaizu , Marcos Lima , Wayne Hu

Modified gravity provides a possible explanation for the currently observed cosmic accelaration. In this paper, we study general classes of modified gravity models. The Einstein-Hilbert action is modified by using general functions of the…

Astrophysics · Physics 2008-11-26 Antonio De Felice , Pia Mukherjee , Yun Wang

We present a systematic comparison of several existing and new void finding algorithms, focusing on their potential power to test a particular class of modified gravity models - chameleon $f(R)$ gravity. These models deviate from standard…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Marius Cautun , Enrique Paillas , Yan-Chuan Cai , Sownak Bose , Joaquin Armijo , Baojiu Li , Nelson Padilla

Many models of quintessence predict a time variation of the fundamental constants as well as a composition-dependent gravity like long-range force mediated by the cosmon. We present bounds for the cosmon coupling to matter and radiation…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. Wetterich

Chameleon and similar (symmetron and dilation) theories of gravity can exhibit new and interesting features on cosmological scales whilst screening the modifications on small scales thereby satisfying solar system tests of general…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-17 Jeremy Sakstein

We use the cosmic shear data from the Canada-France-Hawaii Telescope Lensing Survey to place constraints on $f(R)$ and {\it Generalized Dilaton} models of modified gravity. This is highly complimentary to other probes since the constraints…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-21 Joachim Harnois-Déraps , Dipak Munshi , Patrick Valageas , Ludovic van Waerbeke , Philippe Brax , Peter Coles , Luca Rizzo

The subject of this paper is to investigate the weak regime covariant scalar-tensor-vector gravity (STVG) theory, known as the MOdified gravity (MOG) theory of gravity. First, we show that the MOG in the absence of scalar fields is…

General Relativity and Quantum Cosmology · Physics 2018-10-09 M. Khurshudyan , N. S. Mazhari , D. Momeni , R. Myrzakulov , M. Raza

We study cosmological constraints on the various accelerating models of the universe using the time evolution of the cosmological redshift of distant sources. The important characteristic of this test is that it directly probes the…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Deepak Jain , Sanjay Jhingan

The possible variation of the electromagnetic fine structure constant $\alpha_e$ on cosmological scales arouses great interests in recent years. The strongly lensed gravitational waves and the electromagnetic counterparts could be used to…

General Relativity and Quantum Cosmology · Physics 2018-09-05 Xin Li , Li Tang , Hai-Nan Lin , Li-Li Wang

We investigate the observational consequences of scalar instabilities in bimetric theory, under the assumption that the Vainshtein mechanism restores general relativity within a certain distance from gravitational sources. We argue that…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-28 Edvard Mortsell , Jonas Enander

We introduce a large class of scalar-tensor theories where gravity becomes stronger at large distances via the exchange of a scalar that mixes with the graviton. At small distances, i.e. large curvature, the scalar is screened via an analog…

High Energy Physics - Theory · Physics 2010-02-17 E. Babichev , C. Deffayet , R. Ziour

We investigate the cosmological dynamics of a class of supersymmetric chameleon models coupled to cold dark matter fermions. Supergravity corrections ensure that these models are efficiently screened in all astrophysical objects of…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-28 Philippe Brax , Anne-Christine Davis , Jeremy Sakstein

Modified theories of gravity provide us with a unique opportunity to generate innovative tests of gravity. In Chameleon f(R) gravity, the gravitational potential differs from the weak-field limit of general relativity (GR) in a mass…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-26 Alejo Stark , Christopher J. Miller , Nicholas Kern , Daniel Gifford , Gong-Bo Zhao , Baojiu Li , Kazuya Koyama , Robert C. Nichol

We consider the effect of modified gravity on the growth of large-scale structures at second order in perturbation theory. We show that modified gravity models changing the linear growth rate of fluctuations are also bound to change,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Francis Bernardeau , Philippe Brax

Scalar modifications of gravity have an impact on the growth of structure. Baryon and Cold Dark Matter (CDM) perturbations grow anomalously for scales within the Compton wavelength of the scalar field. In the late time Universe when…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Philippe Brax , Sébastien Clesse , Anne-Christine Davis

Theories of modified gravity attempt to reconcile physics at the largest and the smallest scales by explaining the accelerated expansion of our universe without introducing the cosmological constant. One class of such theories, known as…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-11 Youngsoo Park , Mark Wyman

We present a framework for embedding scalar-tensor models of screened modifed gravity such as chameleons, symmetrons and environmental dilatons into global supersymmetry. This achieved by secluding the dark sector from both the observable…

High Energy Physics - Theory · Physics 2015-06-12 Philippe Brax , Anne-Christine Davis , Jeremy Sakstein
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