English
Related papers

Related papers: A Fast Route to Non-Linear Clustering Statistics i…

200 papers

We describe and demonstrate the potential of a new and very efficient method for simulating certain classes of modified gravity theories, such as the widely studied $f(R)$ gravity models. High resolution simulations for such models are…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-14 Sownak Bose , Baojiu Li , Alexandre Barreira , Jian-hua He , Wojciech A. Hellwing , Kazuya Koyama , Claudio Llinares , Gong-Bo Zhao

In this work we systematically study the linear and nonlinear structure formation in chameleon theories of modified gravity, using a generic parameterisation which describes a large class of models using only 4 parameters. For this we have…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 Philippe Brax , Anne-C. Davis , Baojiu Li , Hans A. Winther , Gong-Bo Zhao

We present a formalism to study screening mechanisms in modified theories of gravity via perturbative methods in different cosmological scenarios. We consider Einstein frame posed theories that are recast as Jordan frame theories, where a…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Alejandro Aviles , Jorge L. Cervantes-Cota , David F. Mota

This thesis introduces a set of methods for testing models of modified gravity using galaxy clusters. In particular, a technique for constraining models with a chameleon screening is introduced. In addition, the outlined technique is…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Andrius Tamosiunas

Theories in which gravity is weaker on cosmological scales have been proposed to explain the observed acceleration of the universe. The nonlinear regime in such theories is not well studied, though it is likely that observational tests of…

Astrophysics · Physics 2009-11-11 Hans F. Stabenau , Bhuvnesh Jain

Viable modifications of gravity that may produce cosmic acceleration need to be screened in high-density regions such as the Solar System, where general relativity is well tested. Screening mechanisms also prevent strong anomalies in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-22 Lucas Lombriser , Fergus Simpson , Alexander Mead

We implement an adaptation of the COLA approach, a hybrid scheme that combines Lagrangian perturbation theory with an N-body approach, to model non-linear collapse in chameleon and symmetron modified gravity models. Gravitational screening…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-30 Georgios Valogiannis , Rachel Bean

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

Observational evidence implying the accelerated expansion of the universe has been the motivation to develop various classes of modified gravity theories. One of them uses the so-called "screening mechanism", which is successful in…

General Relativity and Quantum Cosmology · Physics 2019-11-18 Noshad Khosravi Largani , Mohammad Taghi Mirtorabi

We revisit a method to incorporate the Vainshtein screening mechanism in N-body simulations proposed by R. Scoccimarro in~\cite{Scoccimarro:2009eu}. We further extend this method to cover a subset of Horndeski theories that evade the bound…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-28 Guilherme Brando , Kazuya Koyama , Hans A. Winther

We consider modified gravity models driven by a scalar field whose effects are screened in high density regions due to the presence of non-linearities in its interaction potential and/or its coupling to matter. Our approach covers…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Philippe Brax , Anne-Christine Davis , Baojiu Li , Hans A. Winther

We present an upgraded version of \textsc{MG-MAMPOSSt}, an extension of the \textsc{MAMPOSSt} algorithm that performs Bayesian fits of models of mass and velocity anisotropy profiles to the distribution of tracers in projected phase space,…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-13 Lorenzo Pizzuti , Ippocratis D. Saltas , Luca Amendola

In the context of scalar tensor theories for gravity, there is a universally adopted hypothesis when running N-body simulations that time derivatives in the equation of motion for the scalar field are negligible. In this work we propose to…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David F. Mota

We perform high resolution N-body simulations for f(R) gravity based on a self-adaptive particle- mesh code MLAPM. The Chameleon mechanism that recovers General Relativity on small scales is fully taken into account by self-consistently…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 Gong-Bo Zhao , Baojiu Li , Kazuya Koyama

We present MG-GLAM, a code developed for the very fast production of full $N$-body cosmological simulations in modified gravity (MG) models. We describe the implementation, numerical tests and first results of a large suite of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-13 César Hernández-Aguayo , Cheng-Zong Ruan , Baojiu Li , Christian Arnold , Carlton M. Baugh , Anatoly Klypin , Francisco Prada

Theoretical differences in the growth of structure offer the possibility that we might distinguish between modified gravity theories of dark energy and \LambdaCDM. A significant impediment to applying current and prospective large scale…

Astrophysics · Physics 2008-11-26 Istvan Laszlo , Rachel Bean

Theories of modified gravity where light scalars with non-trivial self-interactions and non-minimal couplings to matter-chameleon and symmetron theories-dynamically suppress deviations from general relativity in the solar system. On other…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-20 Clare Burrage , Jeremy Sakstein

Several extensions of the standard cosmological model include scalar fields as new degrees of freedom in the underlying gravitational theory. A particular class of these scalar field theories include screening mechanisms intended to hide…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David F. Mota , Hans A. Winther

We present MG-GLAM, a code developed for the very fast production of full $N$-body cosmological simulations in modified gravity (MG) models. We describe the implementation, numerical tests and first results of a large suite of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-13 Cheng-Zong Ruan , César Hernández-Aguayo , Baojiu Li , Christian Arnold , Carlton M. Baugh , Anatoly Klypin , Francisco Prada

We introduce the method and the implementation of a cosmological simulation of a class of metric-variation f(R) models that accelerate the cosmological expansion without a cosmological constant and evade solar-system bounds of small-field…

Astrophysics · Physics 2008-12-30 Hiroaki Oyaizu
‹ Prev 1 2 3 10 Next ›