English
Related papers

Related papers: A Cautionary Note on Cosmological Magnetic Fields

200 papers

The major theoretical limitation for extracting cosmological parameters from the CMB sky lies in the precision with which we can calculate the cosmological recombination process. Uncertainty in the details of hydrogen and helium…

Astrophysics · Physics 2009-11-13 Wan Yan Wong , Adam Moss , Douglas Scott

In certain astrophysical systems the commonly employed ideal magnetohydrodynamics (MHD) approximation breaks down. Here, we introduce novel explicit and implicit numerical schemes of ohmic resistivity terms in the moving-mesh code AREPO. We…

Instrumentation and Methods for Astrophysics · Physics 2018-03-09 Federico Marinacci , Mark Vogelsberger , Rahul Kannan , Philip Mocz , Rüdiger Pakmor , Volker Springel

Many interesting terrestrial and astrophysical scenarios involving magnetic fields can be approached in axial geometry. Even though the Lagrangian smoothed particle hydrodynamics (SPH) technique has been successfully extended to handle…

Instrumentation and Methods for Astrophysics · Physics 2022-07-05 Domingo García-Senz , Robert Wissing , Rubén M. Cabezón

The magnetohydrodynamics (MHD) equations plus 'non-ideal' (Ohmic, Hall, ambipolar) resistivities are widely used to model weakly-ionized astrophysical systems. We show that if gradients in the magnetic field become too steep, the implied…

Earth and Planetary Astrophysics · Physics 2025-10-09 Philip F. Hopkins , Jonathan Squire , Raphael Skalidis , Nadine H. Soliman

We consider the ideal magnetohydrodynamics (MHD) of a shallow fluid layer on a rapidly rotating planet or star. The presence of a background toroidal magnetic field is assumed, and the "shallow water" beta-plane approximation is used. We…

Earth and Planetary Astrophysics · Physics 2015-06-22 Alexander M. Balk

There are at present more then 30 theories about the origin of cosmic magnetic fields at galactic and intergalactic scales. Most of them rely on concepts of elementary particle physics, like phase transitions in the early Universe, string…

Astrophysics · Physics 2007-05-23 E. Battaner , H. Lesch

The $\nu$HDM is the only cosmological model based on Milgromian Dynamics (MOND) with available structure formation simulations. While MOND accounts for galaxies, with a priori predictions for spirals and ellipticals, a light sterile…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-25 Nick Samaras , Sebastian Grandis , Pavel Kroupa

In the single fluid, nonrelativistic, ideal-Magnetohydrodynamic (MHD) plasma description magnetic field lines play a fundamental role by defining dynamically preserved "magnetic connections" between plasma elements. Here we show how the…

Plasma Physics · Physics 2016-04-06 F. Pegoraro

Most early Universe scenarios predict negligible magnetic fields on cosmological scales if they are unprocessed during subsequent expansion of the Universe. We present a new numerical treatment of the evolution of primordial fields and…

Astrophysics · Physics 2009-11-07 Guenter Sigl

In this paper, we use a set of observational $H(z)$ data (OHD) to constrain the $\Lambda$CDM cosmology. This data set can be derived from the differential ages of the passively evolving galaxies. Meanwhile, the $\mathcal {A}$-parameter,…

Astrophysics · Physics 2014-11-18 Hui Lin , Cheng Hao , Xiao Wang , Qiang Yuan , Ze-Long Yi , Tong-Jie Zhang , Bao-Quan Wang

Physical problems with a solution that can be expressed analytically are scarce; this holds even more true for problems set in a cosmological context. Such solutions are, however, invaluable tools for making comparisons between theory,…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-13 Orestis A. Karapiperis , Matthieu Schaller

We describe and test a new version of the adaptive mesh refinement (AMR) cosmological code MASCLET. The new version of the code includes all the ingredients of its previous version plus a description of the evolution of the magnetic field…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Vicent Quilis , José Ma. Martí , Susana Planelles

Magnetic fields play an important role in many astrophysical systems and a detailed understanding of their impact on the gas dynamics requires robust numerical simulations. Here we present a new method to evolve the ideal…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Philip Mocz , Mark Vogelsberger , Lars Hernquist

Advantages of inhomogeneous cosmological models that are exact solutions of Einstein's equations over linearised perturbations of homogeneous models are presented. Examples of effects that can be described in the inhomogeneous ones are…

General Relativity and Quantum Cosmology · Physics 2011-12-05 Andrzej Krasiński

Many astrophysical and terrestrial scenarios involving magnetic fields can be approached in axial geometry. Although the smoothed particle hydrodynamics (SPH) technique has been successfully extended to magneto-hydrodynamics (MHD), a…

Instrumentation and Methods for Astrophysics · Physics 2022-12-14 Domingo García-Senz , Robert Wissing , Rubén M. Cabezón , Eda Vurgun , Manuel Linares

In the recent years, global coronal models have experienced an ongoing increase in popularity as tools for forecasting solar weather. Within the domain of up to 21.5Rsun, magnetohydrodynamics (MHD) is used to resolve the coronal structure…

Solar and Stellar Astrophysics · Physics 2022-11-30 Michaela Brchnelova , Błażej Kuźma , Barbara Perri , Andrea Lani , Stefaan Poedts

Magnetohydrodynamical (MHD) turbulence is ubiquitous in magnetized astrophysical plasmas, and it radically changes a great variety of astrophysical processes. In this review, we give the concept of MHD turbulence and explain the origin of…

Solar and Stellar Astrophysics · Physics 2023-02-24 Elena Popova , Alexandre Lazarian

We propose that cosmological magnetic fields generated in regions of finite spatial dimensions may manifest themselves in the global dynamics of the Universe as `dark energy'. We test our model in the context of spatially flat cosmological…

Astrophysics · Physics 2019-08-19 Ioannis Contopoulos , Spyros Basilakos

Cosmic ray propagation is determined by the properties of interstellar turbulence. The multiphase nature of interstellar medium (ISM) and diversity of driving mechanisms give rise to spatial variation of turbulence properties. Meanwhile,…

High Energy Astrophysical Phenomena · Physics 2021-09-21 Huirong Yan

The conventional $\Lambda$CDM cosmological model supplemented by the inflation concept describes the Universe very well. However, there are still a few concerns: new Planck data impose constraints on the shape of the inflaton potential,…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-03 Branislav Vlahovic , Maxim Eingorn , Cosmin Ilie