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Related papers: Emulation of $f(R)$ modified gravity from $\Lambda…

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Motivated by the fact that cosmological models based on $f(Q)$ gravity are very efficient in fitting observational datasets at both background and perturbation levels, we perform a combined dynamical system analysis of both background and…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Wompherdeiki Khyllep , Jibitesh Dutta , Emmanuel N. Saridakis , Kuralay Yesmakhanova

Coarse-graining (CG) enables molecular dynamics (MD) simulations of larger systems and longer timescales that are otherwise infeasible with atomistic models. Machine learning potentials (MLPs), with their capacity to capture many-body…

Chemical Physics · Physics 2025-12-01 Weilong Chen , Franz Görlich , Paul Fuchs , Julija Zavadlav

We present a field-level emulator for large-scale structure, capturing the cosmology dependence and the time evolution of cosmic structure formation. The emulator maps linear displacement fields to their corresponding nonlinear…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Drew Jamieson , Yin Li , Francisco Villaescusa-Navarro , Shirley Ho , David N. Spergel

Deep learning models have been shown to outperform methods that rely on summary statistics, like the power spectrum, in extracting information from complex cosmological data sets. However, due to differences in the subgrid physics…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-16 Andrea Roncoli , Aleksandra Ćiprijanović , Maggie Voetberg , Francisco Villaescusa-Navarro , Brian Nord

We present a Neural Network based emulator for the galaxy redshift-space power spectrum that enables several orders of magnitude acceleration in the galaxy clustering parameter inference, while preserving 3$\sigma$ accuracy better than…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Svyatoslav Trusov , Pauline Zarrouk , Shaun Cole

In this investigation, we perform an observational statistical analysis in the theory of $ f(R, L_m) $ gravity. The proposed theoretical model is based on the Ricci scalar's non-linear contribution. We use a distinct parameterization for…

General Relativity and Quantum Cosmology · Physics 2024-08-30 J. K. Singh , Shaily , Akanksha Singh , Harshna Balhara , Joao R. L. Santos

We study the evolution of linear cosmological perturbations in f(R) models of accelerated expansion in the physical frame where the gravitational dynamics are fourth order and the matter is minimally coupled. These models predict a rich and…

Astrophysics · Physics 2008-11-26 Yong-Seon Song , Wayne Hu , Ignacy Sawicki

We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of General Relativity (GR) has been tested accurately…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-24 Kazuya Koyama

Reliable analytical modeling of the non-linear power spectrum (PS) of matter perturbations is among the chief pre-requisites for cosmological analyses from the largest sky surveys. This is especially true for the models that extend the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Suhani Gupta , Wojciech A. Hellwing , Maciej Bilicki

We present a GPU-accelerated cosmological simulation code, PhotoNs-GPU, based on algorithm of Particle Mesh Fast Multipole Method (PM-FMM), and focus on the GPU utilization and optimization. A proper interpolated method for truncated…

Instrumentation and Methods for Astrophysics · Physics 2021-12-28 Qiao Wang , Chen Meng

I examine how two specific examples of modified gravity explanations of cosmic acceleration help us understand some general problems confronting cosmological tests of gravity: how do we distinguish modified gravity from dark energy if they…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Wayne Hu

The recent measurements of Cosmic Microwave Background temperature and polarization anisotropies made by the Planck satellite have provided impressive confirmation of the $\Lambda$CDM cosmological model. However interesting hints of slight…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

The cosmological reconstruction scheme for modified $F(R)$ gravity is developed in terms of e-folding (or, redshift). It is demonstrated how any FRW cosmology may emerge from specific $F(R)$ theory. The specific examples of well-known…

High Energy Physics - Theory · Physics 2014-11-20 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Saez-Gomez

We present the first calculation of an intrinsically relativistic quantity in fully non-linear cosmolog- ical large-scale structure studies. Traditionally, non-linear structure formation in standard {\Lambda}CDM cosmology is studied using…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-26 Marco Bruni , Daniel B. Thomas , David Wands

The extensive catalog of $\gamma$-ray selected flat-spectrum radio quasars (FSRQs) produced by \emph{Fermi} during a four-year survey has generated considerable interest in determining their $\gamma$-ray luminosity function (GLF) and its…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Houdun Zeng , Fulvio Melia , Li Zhang

The higher-curvature gravity with boundary terms i.e the $f(Q)$ theories, grounded on non-metricity as a fundamental geometric quantity, exhibit remarkable efficacy in portraying late-time universe phenomena. The aim is to delineate…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Pooja Vishwakarma , Parth Shah

In this work, we present a method for numerically solving the Friedmann equations of modified $f(\mathcal{G})$ gravity in the presence of pressureless matter. This method enables us to predict the redshift behaviour of the Hubble expansion…

General Relativity and Quantum Cosmology · Physics 2024-11-08 Santosh V. Lohakare , Soumyadip Niyogi , B. Mishra

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-02 Y. Myrzakulov , Alnadhief H. A. Alfedeel , M. Koussour , S. Muminov , E. I. Hassan , J. Rayimbaev

In this paper, we study the non-linear matter power spectrum in a specific family of $f(R)$ models that can reproduce the $\Lambda$CDM background expansion history, using high resolution $N$-body simulations based on the {\sc ecosmog} code.…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-13 Jian-hua He , Baojiu Li , Yipeng Jing

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
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