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Related papers: A Cautionary Note on Cosmological Magnetic Fields

200 papers

I discuss whether the standard cosmological models fit the WMAP data well enough to justify parameter estimation with standard assumptions. The observed quadrupole is low (but has significant foreground uncertainty) and drives weak evidence…

Astrophysics · Physics 2017-08-23 Antony Lewis

There have been some issues in the past in attempts to simulate magnetic fields using the Smoothed Particle Hydrodynamics (SPH) method. SPH is well suited to star formation problems because of its Lagrangian nature. We present new, stable…

Astrophysics · Physics 2009-11-10 D. J. Price , J. J. Monaghan

We study a simple magnetohydrodynamical approach in which hydrodynamics and MHD turbulence are coupled in a shell model, with given dynamo constrains in the large scales. We consider the case of a low Prandtl number fluid for which the…

Earth and Planetary Astrophysics · Physics 2015-05-13 Roberto Benzi , Jean-Francois Pinton

We test a class of holographic models for the very early universe against cosmological observations and find that they are competitive to the standard $\Lambda$CDM model of cosmology. These models are based on three dimensional perturbative…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-01 Niayesh Afshordi , Claudio Coriano , Luigi Delle Rose , Elizabeth Gould , Kostas Skenderis

The origin of astrophysical magnetic fields observed in galaxies and clusters of galaxies is still unclear. One possibility is that primordial magnetic fields generated in the early Universe provide seeds that grow through compression and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 C. Fedeli , L. Moscardini

Most of the baryonic matter in the Universe is permeated by magnetic fields which affect many, if not most, of astrophysical phenomena both, in compact sources and in diffuse gas. Recent years have been marked by a worldwide surge of…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-23 Elisabete M. de Gouveia Dal Pino

We present three-dimensional magnetohydrodynamic (MHD) simulations of superbubbles, to study the importance of MHD effects in the interpretation of images from recent surveys of the Galactic plane. These simulations focus mainly on…

Astrophysics · Physics 2009-09-29 J. M. Stil , N. D. Wityk , R. Ouyed , A. R. Taylor

Axisymmetric magnetohydrodynamics (MHD) can be invoked for describing astrophysical magnetized flows and formulated to model stellar magnetospheres including main sequence stars (e.g. the Sun), compact stellar objects [e.g. magnetic white…

Solar and Stellar Astrophysics · Physics 2014-03-05 Lile Wang , Yu-Qing Lou

The lecture is devoted to the comparison of a few models of cosmic recombination kinetics with recent CMB anisotropy data and to corresponding predictions for the upcoming PLANCK mission. The influence of additional sources of ionized…

Astrophysics · Physics 2007-05-23 Pavel D. Naselsky

The current cosmological paradigm, $\Lambda$CDM, is characterized its expansive description of the history of the Universe, its deep connections to particle physics and the large amounts of data that support it. Nonetheless, $\Lambda$CDM's…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-08 Michael S. Turner

Holographic cosmology offers a novel framework for describing the very early Universe in which cosmological predictions are expressed in terms of the observables of a three dimensional quantum field theory (QFT). This framework includes…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Niayesh Afshordi , Elizabeth Gould , Kostas Skenderis

Relativistic magnetohydrodynamics (RMHD) provides an extremely useful description of the low-energy long-wavelength phenomena in a variety of physical systems from quark-gluon plasma in heavy-ion collisions to matters in supernovas, compact…

High Energy Physics - Theory · Physics 2022-09-20 Koichi Hattori , Masaru Hongo , Xu-Guang Huang

This paper presents a systematic literature review focusing on the application of machine learning techniques for deriving observational constraints in cosmology. The goal is to evaluate and synthesize existing research to identify…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Luis Rojas , Sebastián Espinoza , Esteban González , Carlos Maldonado , Fei Luo

We present the data-driven reconstruction of gravitational theories and Dark Energy models on cosmological scales. We showcase the power of present cosmological probes at constraining these models and quantify the knowledge of their…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Marco Raveri

Numerical methods to improve the treatment of magnetic fields in smoothed field magnetohydrodynamics (SPMHD) are developed and tested. Chapter 2 is a review of SPMHD. In Chapter 3, a mixed hyperbolic/parabolic scheme is developed which…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Terrence S. Tricco

The quantum hydrodynamic model for charged particle systems is extended to the cases of non zero magnetic fields. In this way, quantum corrections to magnetohydrodynamics are obtained starting from the quantum hydrodynamical model with…

Plasma Physics · Physics 2007-05-23 Fernando Haas

Magnetic helicity is a conserved quantity of ideal magnetohydrodynamics (MHD) that is related to the topology of the magnetic field, and is widely studied in both laboratory and astrophysical plasmas. When the magnetic field has a…

Plasma Physics · Physics 2023-07-28 David MacTaggart , Alberto Valli

We study the effect of inhomogeneities in the matter distribution of the universe on the Faraday rotation of light from distant QSOs and derive new limits on the cosmological magnetic field. The matter distribution in the Universe is far…

Astrophysics · Physics 2009-10-31 Pasquale Blasi , Scott Burles , Angela V. Olinto

It is shown that the standard cosmological model predicts {\it ab initio} generation of large-scale but very small-amplitude cosmic magnetic fields at the epoch of recombination of the primeval plasma. Matter velocities dominated by…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

Comprehending the manner in which magnetic fields affect propagating waves is a first step toward constructing accurate helioseismic models of active region sub-surface structure and dynamics. Here, we present a numerical method to compute…

Astrophysics · Physics 2009-11-13 Shravan M. Hanasoge