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Related papers: Limits for primordial magnetic fields

200 papers

We investigate the origin and evolution of primordial electric and magnetic fields in the early universe, when the expansion is governed by a cosmological constant $\Lambda_0$. Using the gravitoelectromagnetic inflationary formalism with…

General Relativity and Quantum Cosmology · Physics 2009-04-06 Federico Agustin Membiela , Mauricio Bellini

Sufficiently large seeds for generating the observed (inter)galactic magnetic fields emerge naturally in string cosmology from the amplification of electromagnetic vacuum fluctuations due to a dynamical dilaton background. The success of…

High Energy Physics - Theory · Physics 2009-10-28 M. GasperinI , M. Giovannini , G. Veneziano

In this paper we investigate magnetic fields generated in the early Universe. These fields are important candidates at explaining the origin of astrophysical magnetism observed in galaxies and galaxy clusters, whose genesis is still by and…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-19 Stefano Camera , Cosimo Fedeli , Lauro Moscardini

In this paper we show that the Universe is already strongly magnetized at very early epochs during cosmic evolution. Our calculations are based on the efficient amplification of weak magnetic seed fields, which are unavoidably present in…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Jacques M. Wagstaff , Robi Banerjee , Dominik Schleicher , Guenter Sigl

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

The idea that the seed primordial magnetic fields can be explained by the nonminimal coupling between gravitational and electromagnetic fields is discussed. The predicted values of the magnetic field of the spiral galaxies are in agreement…

General Relativity and Quantum Cosmology · Physics 2007-05-23 R. Opher , U. F. Wichoski

Dynamical extra dimensions break the conformal invariance of Maxwell's equations in four dimensions. A higher dimensional background with $n$ contracting extra dimensions and four expanding dimensions is matched to an effectively four…

High Energy Physics - Phenomenology · Physics 2010-04-05 Kerstin E. Kunze

The property of the spectrum of large-scale magnetic fields generated due to the breaking of the conformal invariance of the Maxwell theory through some mechanism in inflationary cosmology is studied. It is shown that the spectrum of the…

Astrophysics · Physics 2008-11-26 Kazuharu Bamba

We discuss generation of magnetic field from cosmological perturbations. We consider the evolution of three component plasma (electron, proton and photon) evaluating the collision term between elecrons and photons up to the second order.…

We describe the generation of the electric current flowing along the external magnetic field in the system of massive charged fermions, possessing anomalous magnetic moments and electroweakly interacting with background matter. This current…

High Energy Physics - Phenomenology · Physics 2019-06-07 Maxim Dvornikov

It is argued that large scale cosmic magnetic field could be generated in the primeval plasma slightly before hydrogen recombination. Non-zero vorticity, necessary for that, might be created by the photon diffusion in the second order in…

Astrophysics · Physics 2016-08-30 Z. Berezhiani , A. D. Dolgov

In this letter, we discuss generation of magnetic field from cosmological perturbations. We consider the evolution of three component plasma (electron, proton and photon) evaluating the collision term between elecrons and photons up to the…

Astrophysics · Physics 2009-11-10 Keitaro Takahashi , Kiyotomo Ichiki , Hiroshi Ohno , Hidekazu Hanayama

The evolution and genesis of Anomalous X-ray Pulsars and Soft Gamma ray Repeaters are investigated. The new arguments in favor of magnetar model are found. It is shown, that these objects are formed from more massive stars and responsible…

Astrophysics · Physics 2008-10-30 F. K. Kasumov , A. O. Allakhverdiev

Enormous progress has been made on observing stellar magnetism in stars from the main sequence through to compact objects. Recent data have thrown into sharper relief the vexed question of the origin of stellar magnetic fields, which…

Solar and Stellar Astrophysics · Physics 2015-06-24 Lilia Ferrario , Andrew Melatos , Jonathan Zrake

We performed cosmological, magneto-hydrodynamical simulations to follow the evolution of magnetic fields in galaxy clusters, exploring the possibility that the origin of the magnetic seed fields are galactic outflows during the star-burst…

Astrophysics · Physics 2009-11-13 J. Donnert , K. Dolag , H. Lesch , E. Müller

The possible existence of a primordial magnetic field in the universe has been previously investigated in many articles. Studies involving the influence of a magnetic field in the nucleosyntesis era, studies considering the effects in the…

Astrophysics · Physics 2009-10-30 J. C. N. de Araujo , R. Opher

We argue that the first stars may have spanned the conventional mass range rather than be identified with the Very Massive Objects (100-1000 solar masses) favoured by numerical simulations. Specifically, we find that magnetic field…

Astrophysics · Physics 2008-11-26 Joseph Silk , Mathieu Langer

Despite the widespread presence of magnetic fields, their origin, evolution and role are still not well understood. Primordial magnetism sounds appealing but is not problem free. The magnetic implications for the large-scale structure of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Christos G. Tsagas

Primordial magnetic fields are often thought to be the early Universe seeds that have bloomed into what we observe today as galactic and extra-galactic magnetic fields. Owing to their minuscule strength, primordial magnetic fields are very…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-11 Sabir Ramazanov , Federico R. Urban , Alexander Vikman

Most of the visible matter in the Universe is ionized, so that cosmic magnetic fields are quite easy to generate and due to the lack of magnetic monopoles hard to destroy. Magnetic fields have been measured in or around practically all…

Astrophysics of Galaxies · Physics 2023-10-06 Rainer Beck , Richard Wielebinski