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We investigate turbulence generated by cosmological structure formation by means of large eddy simulations using adaptive mesh refinement. In contrast to the widely used implicit large eddy simulations, which resolve a limited range of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 W. Schmidt , A. S. Almgren , H. Braun , J. F. Engels , J. C. Niemeyer , J. Schulz , R. R. Mekuria , A. J. Aspden , J. B. Bell

Three-dimensional (3D) high-speed compressible flow is a typical nonlinear, nonequilibrium, and multiscale complex flow. Traditional fluid mechanics models, based on the quasi-continuum assumption and near-equilibrium approximation, are…

Fluid Dynamics · Physics 2025-04-14 Qinghong Guo , Yanbiao Gan , Bin Yang , Yanhong Wu , Huilin Lai , Aiguo Xu

In the present paper we give a brief summary of some recent theoretical advances in the treatment of inhomogeneous fluids and methods which have applications in the study of dynamical properties of liquids in situations of extreme…

Statistical Mechanics · Physics 2015-07-15 Umberto Marini Bettolo Marconi , Simone Melchionna

A new N-body and hydrodynamical code, called RAMSES, is presented. It has been designed to study structure formation in the universe with high spatial resolution. The code is based on Adaptive Mesh Refinement (AMR) technique, with a tree…

Astrophysics · Physics 2014-10-13 Romain Teyssier

This paper develops a renormalized perturbation theory framework for nonlinear structure formation in a broad class of modified gravity models that exhibit Vainshtein screening, with a focus on a viable subclass of Horndeski theories. We…

General Relativity and Quantum Cosmology · Physics 2025-08-29 Luca Amendola , Carla Bernal , Radouane Gannouji

We present $\mathcal{H}\mathtt{-EFTCAMB}$, the official successor to $\mathtt{EFTCAMB}$. The original $\mathtt{EFTCAMB}$ is designed as a consistent and numerically stable implementation of the effective field theory (EFT) of dark energy in…

General Relativity and Quantum Cosmology · Physics 2026-03-30 Gen Ye , Shijie Lin , Jiaming Pan , Dani de Boe , Stan Verhoeve , Marco Raveri , Bin Hu , Noemi Frusciante , Alessandra Silvestri

Observational constraints are considered on a $w_{log}$CDM model of the dark energy equation of state, $w_{d}(z) = w_{0} + w_{a}\left( \frac{\ln(2+z)}{1+z} - \ln 2 \right)$, using the most recent cosmological datasets including DESI Baryon…

General Physics · Physics 2026-03-10 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

Many problems of theoretical and practical interest involve finding a convex or concave function. For instance, optimization problems such as finding the projection on the convex functions in $H^k(\Omega)$, or some problems in economics. In…

Numerical Analysis · Mathematics 2008-04-11 Néstor Aguilera , Pedro Morin

DESI aims to provide one of the tightest constraints on cosmological parameters by analysing the clustering of more than thirty million galaxies. However, obtaining such constraints requires special care in validating the methodology and…

Based upon the intrinsic symmetries approach to inhomogeneous cosmologies, we propose an exact solution to Einstein's field equations where the spatial sections are flat and the source is a non-perfect fluid such that the dissipative terms…

General Relativity and Quantum Cosmology · Physics 2021-03-11 E. Bittencourt , L. G. Gomes , G. B. Santos

Classical density-functional theory provides an efficient alternative to molecular dynamics simulations for understanding the equilibrium properties of inhomogeneous fluids. However, application of density-functional theory to multi-site…

Computational Physics · Physics 2014-02-14 Ravishankar Sundararaman , T. A. Arias

Recent interest in New Early Dark Energy (NEDE), a cosmological model with a vacuum energy component decaying in a triggered phase transition around recombination, has been sparked by its impact on the Hubble tension. Previous constraints…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-02 Juan S. Cruz , Steen Hannestad , Emil Brinch Holm , Florian Niedermann , Martin S. Sloth , Thomas Tram

In this work we investigate the spherical collapse model in flat FRW dark energy universes. We consider the Holographic Dark Energy (HDE) model as a dynamical dark energy scenario with a slowly time-varying equation-of-state (EoS) parameter…

General Relativity and Quantum Cosmology · Physics 2015-01-27 Tayebe Naderi , Mohammad Malekjani , Francesco Pace

We study a model describing the slow flow of a fluid through a deformable, porous, elastic solid undergoing small deformations. The stress-strain relationship of the solid incorporates nonlinear effects, formulated as a perturbation of the…

Numerical Analysis · Mathematics 2026-04-28 Andrea Bonito , Vivette Girault , Diane Guignard

Direct and large eddy simulations of hydrodynamic and hydromagnetic turbulence have been performed in an attempt to isolate artifacts from real and possibly asymptotic features in the energy spectra. It is shown that in a hydrodynamic…

Astrophysics · Physics 2007-05-23 N. E. L. Haugen , A. Brandenburg

We put forth a dynamic modeling framework for sub-grid parametrization of large eddy simulation of turbulent flows based upon the use of the approximate deconvolution procedure to compute the Smagorinsky constant self-adaptively from the…

Fluid Dynamics · Physics 2016-05-02 Romit Maulik , Omer San

Perfect cosmological hyperfluids generalize the concept of a perfect fluid within the framework of metric affine gravity. These hyperfluids encode the microstructure of matter including shear, dilation, and spin via the hypermomentum…

General Relativity and Quantum Cosmology · Physics 2025-08-13 Himanshu Chaudhary , Saddam Hussain

Hydrodynamics can be consistently formulated on surfaces of arbitrary co-dimension in a background space-time, providing the effective theory describing long-wavelength perturbations of black branes. When the co-dimension is non-zero, the…

High Energy Physics - Theory · Physics 2014-12-23 Jay Armas

We investigate Kaniadakis-holographic dark energy by confronting it with observations. We perform a Markov Chain Monte Carlo analysis using cosmic chronometers, supernovae type Ia, and Baryon Acoustic Oscillations data. Concerning the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 A. Hernández-Almada , Genly Leon , Juan Magaña , Miguel A. García-Aspeitia , V. Motta , Emmanuel N. Saridakis , Kuralay Yesmakhanova

A linear relationship between the Hubble expansion parameter and the time derivative of the scalar field is explored in order to derive exact cosmological, attractor-like solutions, both in Einstein's theory and in Brans-Dicke gravity with…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Olga Arias , Tame Gonzalez , Yoelsy Leyva , Israel Quiros