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Related papers: A Holographic Bound on Cosmic Magnetic Fields

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Recently, Sun et al. (2008) published new Galactic 3D-models of magnetic fields in the disk and halo of the Milky Way and the distribution of cosmic-ray electron density by taking into account the thermal electron density model NE2001 by…

Astrophysics of Galaxies · Physics 2015-05-20 Xiaohui Sun , Wolfgang Reich

We consider a neutral holographic plasma with dynamical electromagnetic interactions in a finite external magnetic field. The Coulomb interactions are introduced via mixed boundary conditions for the Maxwell gauge field. The collective…

High Energy Physics - Theory · Physics 2021-06-07 Matteo Baggioli , Ulf Gran , Marcus Tornsö

AdS black holes with hyperbolic horizons provide strong-coupling descriptions of thermal CFT states on hyperboloids. The low-temperature limit of these systems is peculiar. In this note we show that, in addition to a large ground state…

High Energy Physics - Theory · Physics 2016-01-27 Jose L. F. Barbon , Javier Martin-Garcia

The origin of the substantial magnetic fields that are found in galaxies and on even larger scales, such as in clusters of galaxies, is yet unclear. If the second-order couplings between photons and electrons are considered, then…

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

Recently the lower bounds of the intergalactic magnetic fields $10^{-16} \sim 10^{-20}$ Gauss are set by gamma-ray observations while it is unlikely to generate such large scale magnetic fields through astrophysical processes. It is known…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-17 Shohei Saga , Maresuke Shiraishi , Kiyotomo Ichiki , Naoshi Sugiyama

Radio quasar sightlines with strong MgII absorption lines display statistically enhanced Faraday Rotation Measures (RM) indicating the presence of additional magneto-active plasma with respect to sightlines free of such absorption. In this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 M. L. Bernet , F. Miniati , S. J. Lilly

We study thermalization of strongly coupled gauge theory plasma in the presence of magnetic field using the AdS/CFT correspondence. We utilize the falling energy-shell model as a holographic description of gauge theory plasma undergoing…

High Energy Physics - Phenomenology · Physics 2015-11-06 Kiminad A. Mamo , Ho-Ung Yee

A decade ago, there was very limited knowledge of magnetic fields of our Galaxy. The local fields in the Solar vicinity were known to be directed towards a Galactic longitude $l\sim~90^{\circ}$ with reversed directions at smaller…

Astrophysics · Physics 2007-05-23 J. L. Han

We explore the possibility that matter bulk flows could generate the required vorticity in the electron-proton-photon plasma to source cosmic magnetic fields through the Harrison mechanism. We analyze the coupled set of perturbed Maxwell…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-05 J. A. R. Cembranos , A. L. Maroto , H. Villarrubia-Rojo

In the present letter we use holographic methods to show that a very intense magnetic field lowers the temperature at which the mesons melt and decreases the mass gap of the spectrum along with their masses. Consequently, there is a range…

High Energy Physics - Theory · Physics 2019-07-10 Daniel Ávila , Leonardo Patiño

A possible explanation for the origin of the magnetic fields observed today in matter structures is that they were generated in the primordial universe. After briefly revising the model of a primordial stochastic magnetic field and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Chiara Caprini

The generation of a magnetic field in the Early Universe is considered, due to the gravitational production of the Z-boson field during inflation. Scaled to the epoch of galaxy formation this magnetic field suffices to trigger the galactic…

Astrophysics · Physics 2017-01-25 Konstantinos Dimopoulos

We derive an upper limit of $B_0<3.4\times 10^{-9}(\Omega_0h_{50}^2)^{1/2}$ Gauss on the present strength of any primordial homogeneous magnetic field. The microwave background anisotropy created by cosmological magnetic fields is…

Astrophysics · Physics 2016-08-30 John D. Barrow , Pedro G. Ferreira , Joseph Silk

Blazar observations point toward the possible presence of magnetic fields over intergalactic scales of the order of up to $\sim1\,$Mpc, with strengths of at least $\sim10^{-16}\,$G. Understanding the origin of these large-scale magnetic…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-17 Tina Kahniashvili , Axel Brandenburg , Arthur Kosowsky , Sayan Mandal , Alberto Roper Pol

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

Helical intergalactic magnetic fields at the $\sim 10^{-14}~{\rm G}$ level on $\sim 10~{\rm Mpc}$ length scales are indicated by current gamma ray observations. The existence of magnetic fields in cosmic voids and their non-trivial helicity…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Tanmay Vachaspati

The generalized Second Law of thermodynamics and the Holographic Principle are combined to obtain the maximum mass of black holes formed inside a static spherical box of size $R$ filled with radiation at initial temperature $T_{i}$. The…

General Relativity and Quantum Cosmology · Physics 2017-01-18 P. S. Custodio , J. E. Horvath

Primordial magnetic fields may account for all or part of the fields observed in galaxies. We consider the evolution of the magnetic fields created by pseudoscalar effects in the early universe. Such processes can create force-free fields…

Astrophysics · Physics 2009-10-31 George B. Field , Sean M. Carroll

In this thesis, we aim to investigate the mechanisms underlying the genesis of magnetic fields in the Universe and explore their potential in addressing the matter-antimatter asymmetry. We construct consistent models that generate the…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Ashu Kushwaha