English
Related papers

Related papers: Cosmological Magnetic Fields: Their Generation, Ev…

200 papers

The origin of large-scale magnetic fields in cosmic structures and the intergalactic medium is still poorly understood. We explore the effects of non-minimal couplings of electromagnetism on the cosmological evolution of currents and…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-10 Lukas Hollenstein , Rajeev Kumar Jain , Federico R. Urban

We consider grand unified theories with superconducting cosmic strings and which admit the mechanism for generating primordial magnetic fields recently discussed by Vachaspati. We show that these models are severely constrained by…

High Energy Physics - Phenomenology · Physics 2009-10-22 Robert H. Brandenberger , Anne-Christine Davis , Andrew M. Matheson , Mark Trodden

Observational evidence for strong magnetic fields throughout the envelopes of evolved stars is increasing. Many of the instruments coming on line in the near-future will be able to make further contributions to this field. Specifically,…

Solar and Stellar Astrophysics · Physics 2010-10-07 Wouter Vlemmings

The main motivations and challenges related with the physics of large-scale magnetic fields are briefly analyzed. The interplay between large-scale magnetic fields and scalar CMB anisotropies is addressed with specific attention on recent…

Astrophysics · Physics 2008-11-26 Massimo Giovannini

Magnetic fields of debated origin appear to permeate the Universe on all large scales. There is mounting evidence that supernovae produce not only roughly spherical ejecta and winds, but also highly relativistic jets of ordinary matter.…

Astrophysics · Physics 2009-11-11 Arnon Dar , A. De Rujula

The evolution of the magnetic field is investigated for isolated as well as binary neutron stars. The overall nature of the field evolution is seen to be similar for an initial crustal field and an expelled flux. The major uncertainties of…

Astrophysics · Physics 2007-05-23 Sushan Konar , Dipankar Bhattacharya

Applying the known physics of plasmas to the evolution of galaxies and quasars in the Early Universe, a unique "Strong" Magnetic Field Modsl (SMF) was created that explains the origin of a very large-scale primordial magnetic field in each…

Astrophysics · Physics 2007-05-23 Howard D. Greyber

We show that an inhomogeneous cosmological lepton number may have produced turbulence in the primordial plasma when neutrinos entered (almost) free-streaming regime. This effect may be responsible for the origin of cosmic magnetic fields…

Astrophysics · Physics 2009-11-06 A. D. Dolgov , D. Grasso

It is demonstrated that strong magnetic fields are produced from a zero initial magnetic field during the pregalactic era, when galaxies are first forming. Their development proceeds in three phases. In the first phase, weak magnetic fields…

Astrophysics · Physics 2011-02-11 Russell M. Kulsrud , Renyue Cen , Jeremiah P. Ostriker , Dongsu Ryu

While the presence of magnetic fields on low-mass stars is attributed to a dynamo process essentially driven by convective motions, the existence of magnetic fields on intermediate-mass stars has very likely other reasons. Presuming that…

Solar and Stellar Astrophysics · Physics 2013-09-30 Rainer Arlt

The generation of primordial magnetic seed fields during inflation is studied in a theory derived from the one-loop vacuum polarization effective action of the photon in a curved background. This includes terms which couple the curvature to…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Kerstin E. Kunze

We investigate the cosmological evolution of large- and small-scale magnetic fields in galaxies at high redshifts. Results from simulations of hierarchical structure formation cosmology provide a tool to develop an evolutionary model of…

Astrophysics · Physics 2009-11-13 Tigran G. Arshakian , Rainer Beck , Marita Krause , Dmitry Sokoloff

Both observations and modelling of magnetic fields in the diffuse interstellar gas of spiral galaxies are well developed but the theory has been confronted with observations for only a handful of individual galaxies. There is now sufficient…

Astrophysics of Galaxies · Physics 2015-06-23 Cameron Van Eck , Jo-Anne Brown , Anvar Shukurov , Andrew Fletcher

We propose a mechanism for the generation of magnetic fields on cosmological scales that is operative after recombination. An essential ingredient is an instability (of parametric resonance type) of the electromagnetic field driven by an…

High Energy Physics - Phenomenology · Physics 2025-02-27 Robert Brandenberger , Jürg Fröhlich , Hao Jiao

In this work we consider an extended electromagnetic theory in which the scalar state which is usually eliminated by means of the Lorenz condition is allowed to propagate. This state has been shown to generate a small cosmological constant…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-01 Jose Beltran Jimenez , Antonio L. Maroto

The growing sample of magnetic stars shows a remarkable diversity in the properties of their magnetic fields. The overall goal of current studies is to understand the origin, evolution, and structure of stellar magnetic fields in stars of…

Solar and Stellar Astrophysics · Physics 2019-10-16 Swetlana Hubrig , Markus Schöller

In the standard cosmological model, magnetic fields and vorticity are generated during the radiation era via second-order density perturbations. In order to clarify the complicated physics of this second-order magnetogenesis, we use a…

Astrophysics · Physics 2008-11-26 Tsutomu Kobayashi , Roy Maartens , Tetsuya Shiromizu , Keitaro Takahashi

A symmetry-breaking phase transition in the early universe could have led to the formation of cosmic defects. Because these defects dynamically excite not only scalar and tensor type cosmological perturbations but also vector type ones,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Kouichirou Horiguchi , Kiyotomo Ichiki , Toyokazu Sekiguchi , Naoshi Sugiyama

The strength and spectrum of the extragalactic magnetic field are still unknown. Its measurement would help answer the question of whether galactic fields are purely a primordial relic or were dynamically enhanced from a much smaller…

Astrophysics · Physics 2009-10-28 Sangjin Lee , Angela Olinto , Guenter Sigl

Cosmic superstrings are produced at the end of brane inflation. Their properties are similar to cosmic strings arising in grand unified theories. Like cosmic strings they can give rise to a primordial magnetic field, as a result of vortical…

High Energy Physics - Phenomenology · Physics 2009-11-11 Anne-Christine Davis , Konstantinos Dimopoulos