English
Related papers

Related papers: Systematic simulations of modified gravity: symmet…

200 papers

We present a systematic study of modified gravity (MG) models containing a single scalar field non-minimally coupled to the metric. Despite a large parameter space, exploiting the effective field theory of dark energy (EFT of DE)…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-26 Louis Perenon

Observations on galactic scales seem to be in contradiction with recent high resolution N-body simulations. This so-called cold dark matter (CDM) crisis has been addressed in several ways, ranging from a change in fundamental physics by…

Astrophysics · Physics 2008-11-26 Alexander Knebe , Brett Little , Ranty Islam , Julien Devriendt , Asim Mahmood , Joe Silk

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

We present a general method to compute the nonlinear matter power spectrum for dark energy and modified gravity scenarios with percent-level accuracy. By adopting the halo model and nonlinear perturbation theory, we predict the reaction of…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-16 Matteo Cataneo , Lucas Lombriser , Catherine Heymans , Alexander Mead , Alexandre Barreira , Sownak Bose , Baojiu Li

We analyze how to parametrize general modifications of the dark matter perturbations equations in a model-independent way. We prove that a general model with an imperfect and non-conserved dark matter fluid with bulk and shear viscosities…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-17 Miguel Aparicio Resco , Antonio L. Maroto

In theories of modified gravity with the chameleon screening mechanism, the strength of the fifth force depends on environment. This induces an environment dependence of structure formation, which differs from $\Lambda$CDM. We show that…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Joaquin Armijo , Yan-Chuan Cai , Nelson Padilla , Baojiu Li , John A. Peacock

We study Modified Gravity (MG) theories by modelling the redshifted matter power spectrum in a spherical Fourier-Bessel (sFB) basis. We use a fully non-linear description of the real-space matter power-spectrum and include the lowest-order…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Dipak Munshi , Geraint Pratten , Patrick Valageas , Peter Coles , Philippe Brax

In this paper we analyze a suite of cosmological simulations of modified gravitational action f(R) models, where cosmic acceleration is induced by a scalar field that acts as a fifth force on all forms of matter. In particular, we focus on…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-23 Héctor Gil-Marín , Fabian Schmidt , Wayne Hu , Raul Jimenez , Licia Verde

In this work, we analyze the Lyman-$\alpha$ forest in cosmological hydrodynamical simulations of chameleon-type f(R) gravity with the goal to assess whether the impact of such models is detectable in absorption line statistics. We carry out…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Christian Arnold , Ewald Puchwein , Volker Springel

We investigate the observational implications of a gravitational model wherein the gravitational constant $G$ and the cosmological constant $\Lambda$ exhibit scale-dependent behavior at the perturbative level, while preserving the General…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Wiliam S. Hipólito-Ricaldi , Rodrigo von Marttens , Felipe de Melo-Santos , Davi C. Rodrigues

We introduce a new code, ECOSMOG, to run N-body simulations for a wide class of modified gravity and dynamical dark energy theories. These theories generally have one or more new dynamical degrees of freedom, the dynamics of which are…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-04 Baojiu Li , Gong-Bo Zhao , Romain Teyssier , Kazuya Koyama

Low energy interactions between particles are often characterised by elastic scattering. Just as electrons undergo Thomson scattering with photons, dark matter particles may experience an analogous form of momentum exchange with dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Marco Baldi , Fergus Simpson

We use baryon acoustic oscillation and redshift space distortion from the completed Baryon Oscillation Spectroscopic Survey, corresponding to data release 12 of the Sloan Digital Sky Survey, combined sample analysis in combination with…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-09 Eva-Maria Mueller , Will Percival , Eric Linder , Shadab Alam , Gong-Bo Zhao , Ariel G. Sánchez , Florian Beutler

A Bayesian statistical analysis using redshift space distortions data is performed to test a model of Symmetric Teleparallel Gravity where gravity is non-metrical. The cosmological background mimics a $\Lambda$CDM evolution but differences…

General Relativity and Quantum Cosmology · Physics 2020-06-15 Bruno J. Barros , Tiago Barreiro , Tomi Koivisto , Nelson J. Nunes

In this work, we investigate the effects of the growth rate scale dependence in the Symmetron modified gravity (MG) model on cosmic structure formation and we analyze the redshift-space distortion (RSD) multipoles, comparing with the…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-19 Gerardo Morales-Navarrete , Jorge L. Cervantes-Cota

Off-diagonal vacuum and nonvacuum configurations in Einstein gravity can mimic physical effects of modified gravitational theories of $f(R,T,R_{\mu \nu}T^{\mu \nu})$ type. To prove this statement, exact and approximate solutions are…

General Relativity and Quantum Cosmology · Physics 2015-07-01 Emilio Elizalde , Sergiu I. Vacaru

We present an analytical description of the probability distribution function (PDF) of the smoothed three-dimensional matter density field for modified gravity and dark energy. Our approach, based on the principles of Large Deviations…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-05 Matteo Cataneo , Cora Uhlemann , Christian Arnold , Alex Gough , Baojiu Li , Catherine Heymans

We present an interpretable emulator for the linear matter power spectrum (MPS) in the standard cosmological model $\Lambda$CDM, constructed via a physics-informed symbolic regression framework. By combining domain knowledge with a machine…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-12 J. Bayron Orjuela-Quintana , Domenico Sapone , Savvas Nesseris

Models of loop quantum gravity based on real connections have a deformed notion of general covariance, which leads to the phenomenon of signature change. This result is confirmed here in a general analysis of all midisuperspace models…

General Relativity and Quantum Cosmology · Physics 2017-07-11 Martin Bojowald , Suddhasattwa Brahma

The observed accelerated expansion of the Universe may be explained by dark energy or the breakdown of general relativity (GR) on cosmological scales. When the latter case, a modified gravity scenario, is considered, it is often assumed…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-04 Jiro Matsumoto , Teppei Okumura , Misao Sasaki
‹ Prev 1 3 4 5 6 7 10 Next ›