English
Related papers

Related papers: Excursion set theory for modified gravity: correla…

200 papers

Chameleon gravity is an example of a model that gives rise to interesting phenomenology on cosmological scales while simultaneously possessing a screening mechanism, allowing it to avoid solar system constraints. Such models result in…

General Relativity and Quantum Cosmology · Physics 2022-06-15 Andrius Tamosiunas , Chad Briddon , Clare Burrage , Weiguang Cui , Adam Moss

We extend the chameleon models by considering Scalar-Fluid theories where the coupling between matter and the scalar field can be represented by a quadratic effective potential with density-dependent minimum and mass. In this context, we…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-09 Philippe Brax , Nicola Tamanini

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

Theories that attempt to explain cosmic acceleration by modifying gravity typically introduces a long-range scalar force that needs to be screened on small scales. One common screening mechanism is the chameleon, where the scalar force is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Philip Chang , Lam Hui

We present a novel combination of the excursion-set approach with the peak theory formalism in Lagrangian space and provide accurate predictions for halo and void statistics over a wide range of scales. The set-up is based on an effective…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-04 Giovanni Verza , Carmelita Carbone , Alice Pisani , Cristiano Porciani , Sabino Matarrese

Globular clusters (GCs) in the Milky Way have characteristic velocity dispersions that are consistent with the predictions of Newtonian gravity, and may be at odds with Modified Newtonian Dynamics (MOND). We discuss a modified gravity (MOG)…

Astrophysics · Physics 2008-06-14 J. W. Moffat , V. T. Toth

The enumeration of weighted walks in the quarter plane reduces to studying a functional equation with two catalytic variables. When the steps of the walk are small, Bousquet-M\'elou and Mishna defined a group called the group of the walk…

Combinatorics · Mathematics 2025-10-16 Pierre Bonnet , Charlotte Hardouin

In recent work (Milgrom 2009, Blanchet & Novak 2011), the authors showed that MOdified Newton Dynamics (MOND) have a non-negligible secular perturbation effect on planets with large semi-major axes (gaseous planets) in the Solar System.…

Earth and Planetary Astrophysics · Physics 2015-04-16 Lucie Maquet , Frédéric Pierret

We investigate nonlocal Lagrangian bias contributions involving gradients of the linear density field, for which we have predictions from the excursion set peak formalism. We begin by writing down a bias expansion which includes all the…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-30 Matteo Biagetti , Kwan Chuen Chan , Vincent Desjacques , Aseem Paranjape

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 search for viable f(R) theories of gravity, making use of the equivalence between such theories and scalar-tensor gravity. We find that models can be made consistent with solar system constraints either by giving the scalar a high mass…

Astrophysics · Physics 2008-11-26 Thomas Faulkner , Max Tegmark , Emory F. Bunn , Yi Mao

We study the impact of primordial non-Gaussianity generated during inflation on the bias of halos using excursion set theory. We recapture the familiar result that the bias scales as $k^{-2}$ on large scales for local type non-Gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-28 Peter Adshead , Eric J. Baxter , Scott Dodelson , Adam Lidz

A model of the gravitationally evolved dark matter distribution, in the Eulerian space, is developed. It is a simple extension of the excursion set model that is commonly used to estimate the mass function of collapsed dark matter haloes.…

Astrophysics · Physics 2009-10-30 Ravi K. Sheth

We investigate the solar-system constraint on the f(R) theory of modified gravity with chameleon mechanism, where f(R) represents the deviation from general relativity in the gravity action. We obtain a stringent bound to a general,…

General Relativity and Quantum Cosmology · Physics 2011-08-09 Je-An Gu , Wei-Ting Lin

The impact of biasing schemes on the clustering of tracers of the large-scale structure is analytically studied in the weakly nonlinear regime. For this purpose, we use the one-loop approximation of the integrated perturbation theory…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-20 Takahiko Matsubara , Vincent Desjacques

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

In order to obtain functional limit theorems for heavy tailed stationary processes arising from dynamical systems, one needs to understand the clustering patterns of the tail observations of the process. These patterns are well described by…

Dynamical Systems · Mathematics 2023-04-19 Raquel Couto

It has been suggested that a monitoring program employing the pixel lensing method to search for microlensing events towards galactic globular clusters may increase the statistics and discriminate among different halo models. Stimulated by…

Astrophysics · Physics 2009-11-07 V. F. Cardone , M. Cantiello

We study the halo mass function (HMF) in modified gravity (MG) models using a set of large $N$-body simulations -- the ELEPHANT suite. We consider two popular beyond-general relativity scenarios: the Hu-Sawicki chameleon $f(R)$ model and…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-22 Suhani Gupta , Wojciech A. Hellwing , Maciej Bilicki , Jorge Enrique García-Farieta

We develop the formalism to include substructure in the halo model of clustering. Real halos are not likely to be perfectly smooth, but have substructure which has so far been neglected in the halo model -- our formalism allows one to…

Astrophysics · Physics 2009-11-07 Ravi K. Sheth , Bhuvnesh Jain
‹ Prev 1 3 4 5 6 7 10 Next ›