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We study how the presence of a background magnetic field, of intensity compatible with current observation constraints, affects the linear evolution of cosmological density perturbations at scales below the Hubble radius. The magnetic field…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-22 Massimiliano Lattanzi , Nakia Carlevaro , Giovanni Montani

We simulate the propagation of cosmic rays at ultra-high energies, $\gtrsim 10^{18}$ eV, in models of extragalactic magnetic fields in constrained simulations of the local Universe. We investigate the impact of different magneto-genesis…

High Energy Astrophysical Phenomena · Physics 2019-02-13 Stefan Hackstein , Franco Vazza , Marcus Brüggen , Jenny G. Sorce , Stefan Gottlöber

Magnetic field configurations extending over macroscopic scale distances are shown to be generated in rarefied collisionless plasmas when non-thermal and spatially inhomogeneous electron distributions in phase space emerge. The analyzed…

Plasma Physics · Physics 2024-08-23 B. Coppi , B. Basu

In this work we consider quantum electromagnetic fields in an expanding universe. We start by reviewing the difficulties found when trying to impose the Lorenz condition in a time-dependent geometry. Motivated by this fact, we explore the…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jose Beltran Jimenez , Antonio L. Maroto

The maximum magnetic field strength generated by Weibel-type plasma instabilities is estimated for typical conditions in the interstellar medium. The relevant kinetic dispersion relations are evaluated by conducting a parameter study both…

High Energy Astrophysical Phenomena · Physics 2015-06-16 R. C. Tautz , J. Triptow

We investigate bounds on the strength of the primordial magnetic field (PMF) from the cosmic microwave background (CMB) bispectra of the intensity (temperature) modes induced from the auto- and cross-correlated bispectra of the scalar and…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-02 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki

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

Weibel-type instability can self-generate and amplify magnetic fields in both space and laboratory plasmas with temperature anisotropy. The electron Weibel instability has generally proven more challenging to measure than its ion…

The existence of magnetic fields in the universe is unmistakable. They are observed at all scales from stars to galaxy clusters. However, the origin of these fields remains enigmatic. It is believed that magnetic field seeds may have…

General Relativity and Quantum Cosmology · Physics 2022-08-17 Orfeu Bertolami , Maria Margarida Lima , Filipe C. Mena

Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-17 Pranjal Trivedi , Kandaswamy Subramanian , T. R. Seshadri

We study primordial magnetic field effects on the matter perturbations in the Universe. We assume magnetic field generation prior to the big bang nucleosynthesis (BBN), i.e. during the radiation dominated epoch of the Universe expansion,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Tina Kahniashvili , Yurii Maravin , Aravind Natarajan , Nicholas Battaglia , Alexander G. Tevzadze

The cosmological magnetic field is one of the important physical quantities which affect strongly the cosmic microwave background (CMB) power spectrum. Recent CMB observations have been extended to higher multipoles $l\gtrsim$1000, and they…

Astrophysics · Physics 2009-11-10 D. G. Yamazaki , K. Ichiki , T. Kajino

The origin of the magnetic field in galaxies is an open question in astrophysics. Several mechanisms have been proposed related, in general, with the generation of small seed fields amplified by a dynamo mechanism. In general, these…

Astrophysics · Physics 2009-10-30 O. D. Miranda , M. Opher , R. Opher

A primordial magnetic field may be generated during an inflationary period if conformal invariance is broken. We reexamine and generalize previous results about the magnetic field produced by couplings of the form $R^n…

Astrophysics · Physics 2009-10-28 F. D. Mazzitelli , F. M. Spedalieri

Origin of the magnetic field ubiquitous in the Universe is studied based on the Biermann mechanism, which is expected to work in the non-barotropic region. We perform a series of two-dimensional MHD simulations of the first generation…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-17 Hidekazu Hanayama , Keitaro Takahashi , Kohji Tomisaka

We consider that no mean magnetic field exists during this epoch, but that there is a mean magnetic energy associated with large-scale magnetic inhomogeneities. We study the evolution of these inhomogeneities and their influence on the…

Astrophysics · Physics 2009-01-14 E. Battaner , E. Florido , J. Jimenez-Vicente

Particle-in-cell simulations are used to investigate the formation of magnetic fields, B, in plasmas with perpendicular electron density and temperature gradients. For system sizes, L, comparable to the ion skin depth, d_i, it is shown that…

Plasma Physics · Physics 2015-06-16 K. M. Schoeffler , N. F. Loureiro , R. A. Fonseca , L. O. Silva

Damping of magnetic fields via ambipolar diffusion and decay of magnetohydrodynamical (MHD) turbulence in the post decoupling era heats the intergalactic medium (IGM). Delayed recombination of hydrogen atoms in the IGM yields an optical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-26 Kerstin E. Kunze , Eiichiro Komatsu

Primordial tangled cosmological Magnetic Fields source rotational velocity perturbations of the baryon fluid, even in the post-recombination universe. These vortical modes inturn leave a characteristic imprint on the temperature anisotropy…

Astrophysics · Physics 2016-08-30 T. R. Seshadri , Kandaswamy Subramanian

We consider the evolution of primordial magnetic fields generated during cosmological, electroweak or QCD, phase transitions. We assume that the magnetic field generation can be described as an injection of magnetic energy to cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-24 Tina Kahniashvili , Alexander G. Tevzadze , Axel Brandenburg , Andrii Neronov