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Related papers: Mixing matters

200 papers

We derive and analyze a class of spherically symmetric cosmological models whose source is an interactive mixture of inhomogeneous cold dark matter (DM) and a generic homogeneous dark energy (DE) fluid. If the DE fluid corresponds to a…

Astrophysics · Physics 2009-11-10 Roberto A Sussman , Israel Quiros , Osmel Martin Gonzalez

Magnetic reconnection is a process that changes magnetic field topology in highly conducting fluids. Within the standard Sweet-Parker model, this process would be too slow to explain observations (e.g. solar flares). In reality, the process…

Astrophysics of Galaxies · Physics 2017-04-05 Grzegorz Kowal , Diego A. Falceta-Gonçalves , Alex Lazarian , Ethan T. Vishniac

We present a one-equation subgrid scale model that evolves the turbulence energy corresponding to unresolved velocity fluctuations in large eddy simulations. The model is derived in the context of the Germano consistent decomposition of the…

Astrophysics · Physics 2009-11-11 W. Schmidt , J. C. Niemeyer , W. Hillebrandt

We discuss the general framework for a perfect continuum medium in cosmology and show that an interesting generalization of the fluids normally used is for the medium to have rigidity and, hence, be analogous to an elastic solid. Such…

Astrophysics · Physics 2008-11-26 Richard A. Battye , Adam Moss

A spatially homogeneous and anisotropic Bianchi type I universe is studied with the interacting holographic and new agegraphic scalar fields models of dark energy. Given, the framework of the anisotropic model, both the dynamics and…

General Relativity and Quantum Cosmology · Physics 2018-08-10 Hossien Hossienkhani , Ali Aghamohammadi , S. W. Rabieei , abdollah Refaei

We present a study of the dynamics of multi-component models of spiral galaxies at various stages of grand merging. Numerical models include a self-consistent account of the dynamics of collisionless stellar subsystems and N-body dark…

Astrophysics of Galaxies · Physics 2025-02-25 Alexander Khoperskov , Sergei Khrapov , Danila Sirotin , Anatoly Zasov

Theoretical approaches to low-frequency magnetized turbulence in collisionless and weakly collisional astrophysical plasmas are reviewed. The proper starting point for an analytical description of these plasmas is kinetic theory, not fluid…

Astrophysics · Physics 2009-11-11 A. A. Schekochihin , S. C. Cowley , W. Dorland

We examine the chemical properties of 5 cosmological hydrodynamical simulations of an M33-like disc galaxy which have been shown to be consistent with the morphological characteristics and bulk scaling relations expected of late-type…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 K. Pilkington , B. K. Gibson , C. B. Brook , F. Calura , G. S. Stinson , R. J. Thacker , L. Michel-Dansac , J. Bailin , H. M. P. Couchman , J. Wadsley , T. R. Quinn , A. Maccio

We ask how the inclusion of various physical heating processes due to the metal content of gas affect the evolution of massive galaxies and compute a suite of cosmological hydrodynamical simulations that follow these systems and their…

Prior studies of non-equilibrium dynamics using anisotropic hydrodynamics have used the relativistic Anderson-Witting scattering kernel or some variant thereof. In this paper, we make the first study of the impact of using a more realistic…

High Energy Physics - Phenomenology · Physics 2018-04-24 Dekrayat Almaalol , Michael Strickland

The bulk viscosity of cosmological fluid and the creation of cold dark matter both result in the generation of irreversible entropy (related to dissipative processes) in a homogeneous and isotropic universe. To consider such effects, the…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-16 Nobuyoshi Komatsu , Shigeo Kimura

In this article we give a full description of the dynamics of the flat anisotropic (4+1)-dimensional cosmological model in the presence of both Gauss-Bonnet and Einstein contributions. This is the first complete description of this model…

General Relativity and Quantum Cosmology · Physics 2010-12-13 S. A. Pavluchenko

Many important problems in astrophysics, space physics, and geophysics involve flows of (possibly ionized) gases in the vicinity of a spherical object, such as a star or planet. The geometry of such a system naturally favors numerical…

Computational Physics · Physics 2020-04-01 V. Florinski , D. S. Balsara , S. Garain , K. F. Gurski

In cosmological simulations of large-scale structure star formation and feedback in galaxies are modelled by so-called sub-grid models, that represent a physically motivated approximation of processes occurring below the resolution limit.…

Astrophysics of Galaxies · Physics 2025-09-24 Eirini Batziou , Ulrich P. Steinwandel , Klaus Dolag , Milena Valentini

The arrival directions of TeV-PeV cosmic rays are remarkably uniform due to the isotropization of their directions by scattering on turbulent magnetic fields. Small anisotropies can exist in standard diffusion models, however, only on the…

High Energy Astrophysical Phenomena · Physics 2022-03-14 Marco Kuhlen , Vo Hong Minh Phan , Philipp Mertsch

Hard models for particle interactions have played a crucial role in the understanding of the structure of condensed matter. In particular, they help to explain the formation of oriented phases in liquids made of anisotropic molecules or…

Soft Condensed Matter · Physics 2015-06-22 Luis Mederos , Enrique Velasco , Yuri Martinez-Raton

Plasma turbulence is a ubiquitous dynamical process that transfers energy across many spatial and temporal scales and affects energetic particle transport. Recent advances in the understanding of compressible magnetohydrodynamic (MHD)…

Solar and Stellar Astrophysics · Physics 2024-02-09 Siqi Zhao , Huirong Yan , Terry Z. Liu , Ka Ho Yuen , Mijie Shi

The acceleration of energetic particle transport in high amplitude magnetosonic and Alfvenic turbulence is considered using the method of Monte Carlo particle simulations, involving integration of particle equations of motion. We derive the…

Astrophysics · Physics 2009-09-25 G. Michalek , M. Ostrowski , R. Schlickeiser

Understanding the statistics of ocean geostrophic turbulence is of utmost importance in understanding its interactions with the global ocean circulation and the climate system as a whole. Here, a study of eddy-mixing entropy in a…

Fluid Dynamics · Physics 2017-02-28 Tomos W. David , Laure Zanna , David P. Marshall

An algorithm for simulating self-gravitating cosmological astrophysical fluids is presented. The advantages include a large dynamic range, parallelizability, high resolution per grid element and fast execution speed. The code is based on a…

Astrophysics · Physics 2009-10-30 Ue-Li Pen