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Related papers: Conformal anomaly and primordial magnetic fields

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Relaxation of the magnetic field in rigidly rotating quark-gluon plasma is studied. It is shown that the infrared modes satisfying $k < |m|\Omega$ and $k< |m\pm 1|\Omega$, where integer $m$ is the projection of the orbital angular momentum…

High Energy Physics - Phenomenology · Physics 2025-04-02 Aritra Das , Kirill Tuchin

Motivated by a scenario of magnetogenesis in which a homogeneous magnetic field is generated during inflation, we study the magnetohydrodynamic evolution of the primordial plasma motions for two kinds of initial conditions -- (i) a…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-28 Axel Brandenburg , Ruth Durrer , Yiwen Huang , Tina Kahniashvili , Sayan Mandal , Shinji Mukohyama

We propose a novel scenario to generate primordial magnetic fields during inflation induced by an oscillating coupling of the electromagnetic field to the inflaton. This resonant mechanism has two key advantages over previous proposals.…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Christian T. Byrnes , Lukas Hollenstein , Rajeev Kumar Jain , Federico R. Urban

It is shown that an unmagnetized nonrelativistic thermal electron-proton plasma spontaneously emits aperiodic turbulent magnetic field fluctuations of strength $|\delta B|=9\beta_eg^{1/3}W_e^{1/2}$ G, where $\beta_e$ is the normalized…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 R. Schlickeiser

Recently, it has been showed that a slow expansion, which is asymptotically a static state in infinite past and may be described as an evolution with \epsilon \ll -1, of early universe may lead to the generation of primordial perturbation…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yun-Song Piao

If cosmic background neutrinos interact very weakly with each other, through spin-spin interactions, then they may have experienced a phase transition, leading to a ferromagnetic ordering. The small magnetic field resulting from…

High Energy Physics - Phenomenology · Physics 2014-07-11 Paola Arias , Jorge Gamboa , Justo Lopez-Sarrion

Motivated by the aim of producing significant number of primordial black holes, over the past few years, there has been a considerable interest in examining models of inflation involving a single, canonical field, that permit a brief period…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Sagarika Tripathy , Debika Chowdhury , H. V. Ragavendra , L. Sriramkumar

In early-type stars a fossil magnetic field may be generated during the star formation process or be the result of a stellar merger event. Surface magnetic fields are thought to be erased by (sub)surface convection layers, which typically…

Solar and Stellar Astrophysics · Physics 2020-06-17 Adam S. Jermyn , Matteo Cantiello

Cosmological inflation provides the initial conditions for the structure formation. However, the origin of large-scale magnetic fields cannot be addressed in this framework. The key issue for this long-standing problem is the conformal…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 Debottam Nandi , S. Shankaranarayanan

We discuss how a cosmological magnetic field could affect the expansion of the universe, through its interaction with the spacetime geometry. The tension of the field lines means that the magneto-curvature coupling tends to accelerate…

Astrophysics · Physics 2009-10-31 D. R. Matravers , C. G. Tsagas

The amplification of magnetic fields in a highly conducting fluid is studied numerically. During growth, the magnetic field is spatially intermittent: it does not uniformly fill the volume, but is concentrated in long thin folded…

Chaotic Dynamics · Physics 2009-11-10 A. A. Schekochihin , S. C. Cowley , J. L. Maron , J. C. McWilliams

The simplest gauge invariant models of inflationary magnetogenesis are known to suffer from the problems of either large backreaction or strong coupling, which make it difficult to self-consistently achieve cosmic magnetic fields from…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Ricardo J. Z. Ferreira , Rajeev Kumar Jain , Martin S. Sloth

Recent numerical studies suggest that magnetic fields play an important role in primordial star formation in the early universe. However, the detailed evolution of the magnetic field in the collapse phase still has uncertainties because of…

Astrophysics of Galaxies · Physics 2024-02-27 Sho Higashi , Hajime Susa , Christoph Federrath , Gen Chiaki

This dissertation studies the quantum anomalous effects on the description of high energy electrodynamics. We argue that on the temperatures comparable to the electroweak scale, characteristic for the early Universe and objects like neutron…

High Energy Physics - Phenomenology · Physics 2021-02-23 Petar Pavlović

We discuss whether an unaccounted contribution to the Cosmic Microwave Background polarization $B$-mode by primordial magnetic fields (PMFs) can bias future constraints on inflationary gravitational waves. As a case-study, we consider a…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Fabrizio Renzi , Giovanni Cabass , Eleonora Di Valentino , Alessandro Melchiorri , Luca Pagano

A period of rapidly accelerating expansion is expected in the early Universe implemented by a scalar field slowly rolling down along an asymptotically flat potential preferred by the current data. In this paper, we point out that this…

General Relativity and Quantum Cosmology · Physics 2022-09-01 Rong-Gen Cai , Yu-Shi Hao , Shao-Jiang Wang

We investigate the symmetry constraints on the bispectrum, i.e. the three-point correlation function of primordial density fluctuations, in slow-roll inflation. It follows from the defining property of slow-roll inflation that primordial…

High Energy Physics - Theory · Physics 2013-03-29 Koenraad Schalm , Gary Shiu , Ted van der Aalst

There is an observational indication of extragalactic magnetic fields. No known astrophysical process can explain the origin of such large scale magnetic fields, which motivates us to look for their origin in primordial inflation. By…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Teruaki Suyama , Jun'ichi Yokoyama

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

An appealing feature of inflationary cosmology is the presence of a phase-space attractor, "slow roll", which washes out the dependence on initial field velocities. We investigate the robustness of this property under backreaction from…

General Relativity and Quantum Cosmology · Physics 2021-04-05 Julien Grain , Vincent Vennin
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