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Related papers: Magnetized cosmic walls

200 papers

We consider a scale-invariant helical magnetic field generated during inflation. We show that, if the mean magnetic helicity density of such a field is measured, it can be used to determine a lower bound on the duration of inflation. Upper…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-13 Tina Kahniashvili , Axel Brandenburg , Ruth Durrer , Alexander G. Tevzadze , Winston Yin

In this manuscript, we studied the accelerated expansion history of the universe and the formations of large-scale structures using $f(Q)$ gravity model. The expansion rate of the universe within distance modulus and redshift has been…

General Relativity and Quantum Cosmology · Physics 2022-06-07 Shambel Sahlu , Endalkachew Tsegaye

An approach to cosmological modelling is presented that incorporates the inhomogeneous structure of the Cosmic Web, specifically focusing on the interplay between cosmic voids and density walls. We extend the standard homogeneous and…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-12 John Moffat

We investigate an electromagnetic instability in two-dimensional materials arising from an anisotropy of the Fermi surface, utilizing a kinetic model accounting for the effects of the values of temperature, chemical potential and anisotropy…

Materials Science · Physics 2025-06-27 Diogo Simões , Hugo Terças , Jorge Ferreira

Some common properties of helical magnetic fields in decaying and driven turbulence are discussed. These include mainly the inverse cascade that produces fields on progressively larger scales. Magnetic helicity also restricts the evolution…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

In most of the literature on evolution of cosmological magnetic fields, it is found that large-scale magnetic fields evolve as $B^{2}\propto a^{-4}$ (adiabatic magnetic decay) where $a$ is the cosmological scale factor and $B$ is the…

General Relativity and Quantum Cosmology · Physics 2020-04-23 Timothy Oreta , Bob Osano

In this paper, we have investigated the density perturbations and cosmological evolution in the FLRW universe in presence of a cosmic magnetic field, which may be assumed to mimic primordial magnetic fields. Such magnetic fields have…

High Energy Physics - Theory · Physics 2025-08-11 Samarjit Chakraborty , Sarbari Guha

The structure and properties of a geometrically constrained magnetic wall in a constriction separating two wider regions are investigated theoretically. They are shown to differconsiderably from those of an unconstrained wall, so that the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Patrick Bruno

We show, using a covariant and gauge-invariant charged multifluid perturbation scheme, that velocity perturbations of the matter-dominated dust Friedmann-Lemaitre-Robertson-Walker (FLRW) model can lead to the generation of cosmic magnetic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Gerold Betschart , Peter K. S. Dunsby , Mattias Marklund

Exact solutions of the perturbations equations in the magnetized LambdaCDM scenario are presented. They apply during the dark ages and, more specifically, after the baryons are freed from the drag of the photons. The magnetized growth rate…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-25 Massimo Giovannini

Magnetic fields of laboratory, planetary, stellar, and galactic plasmas commonly exhibit significant order on large temporal or spatial scales compared to the otherwise random motions within the hosting system. Such ordered fields can be…

Solar and Stellar Astrophysics · Physics 2015-06-18 Eric G. Blackman

In this Letter, we report a realistic calculation of the magnetic field profile for the equation of state inside strongly magnetized neutron stars. Unlike previous estimates, which are widely used in the literature, we find that magnetic…

High Energy Astrophysical Phenomena · Physics 2017-10-11 V. Dexheimer , B. Franzon , R. O. Gomes , R. L. S. Farias , S. S. Avancini , S. Schramm

The current standard cosmological model is constructed within the framework of general relativity with a cosmological constant $\Lambda$, which is often associated with dark energy, and phenomenologically explains the accelerated cosmic…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Jiamin Hou , Julian Bautista , Maria Berti , Carolina Cuesta-Lazaro , César Hernández-Aguayo , Tilman Tröster , Jinglan Zheng

Magnetic fields have been observed in galaxies, clusters of galaxies and probably in superclusters. While mechanisms exist to generate these in the late universe, it is possible that magnetic fields have existed since very early times. This…

Astrophysics · Physics 2009-12-07 Iain A. Brown

Observational manifestations of some models of modified gravity, which have been suggested to explain the accelerated cosmological expansion, are analyzed for gravitating systems with time dependent mass density. It is shown that if the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 E. V. Arbuzova , A. D. Dolgov

It is widely believed that primordial magnetic fields are dramatically diluted by the expansion of the universe. As a result, cosmological magnetic fields with residual strengths of astrophysical relevance are generally sought by going…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 John D. Barrow , Christos G. Tsagas

A new mechanism for the evolution of primordial magnetic fields is described and analysed. The field evolution is followed from the time of its creation until the epoch of structure and galaxy formation. The mechanism takes into account the…

Astrophysics · Physics 2009-10-28 K. Dimopoulos , A. C. Davis

We investigate in more depth the issue of backreaction in models that attempt at generating cosmological magnetic fields at inflation. By choosing different, physically motivated, parametrisations, we are able to isolate the core of the…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-14 Federico R. Urban

We study multidimensional cosmological models with a higher-dimensional product manifold, that consists of spherical and flat spaces, in the presence of a minimal free scalar field. Dynamical behaviour of the model is analyzed both in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Baukh Victor

Viable models of modified gravity designed to produce cosmic acceleration at the current epoch, closely mimic the $\Lambda$CDM model at the level of background cosmology. However, this degeneracy is generically broken at the level of linear…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Alessandra Silvestri