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We investigate the gravitational wave production induced by the primordial magnetic fields in a parity-violating magnetogenesis model. It is shown that the gravitational waves detectable by LISA, DECIGO or BBO and the magnetic fields strong…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-17 So Okano , Tomohiro Fujita

Cosmic magnetic fields may be generated during early cosmic phase transition, such as the QCD- or electroweak- transitions. The magnitude of the remainder of such fields at the present epoch crucially depends on the exponent $n$ of their…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-02 Karsten Jedamzik , Guenter Sigl

We propose a mechanism to generate large-scale magnetic fields with correlation lengths of 100 kpc. Domain walls with QCD scale internal structure form and coalesce obtaining Hubble scale correlations and align nucleon spins. Due to strong…

High Energy Physics - Phenomenology · Physics 2009-10-31 Michael McNeil Forbes , Ariel R. Zhitnitsky

We show that the relatively strong magnetic fields ($\ge 1 \mu$G) in high redshift objects can be explained by the combined action of an evolving protogalactic fluctuation and electrodynamic processes providing the magnetic seed fields.…

Astrophysics · Physics 2007-05-23 Harald Lesch , Masashi Chiba

We revisit the big bang nucleosynthesis (BBN) limits on primordial magnetic fields and/or turbulent motions accounting for the decaying nature of turbulent sources between the time of generation and BBN. This leads to larger estimates for…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Tina Kahniashvili , Emma Clarke , Jonathan Stepp , Axel Brandenburg

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…

If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field---e.g. the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Robert R. Caldwell , Leonardo Motta , Marc Kamionkowski

The generation of large-scale magnetic fields is studied in inflationary cosmology. We consider the violation of the conformal invariance of the Maxwell field by dilatonic as well as non-minimal gravitational couplings. We derive a general…

Astrophysics · Physics 2009-11-11 Kazuharu Bamba , Misao Sasaki

We review current ideas on the origin of galactic and extragalactic magnetic fields. We begin by summarizing observations of magnetic fields at cosmological redshifts and on cosmological scales. These observations translate into constraints…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lawrence M. Widrow , Dongsu Ryu , Dominik Schleicher , Kandaswamy Subramanian , Christos G. Tsagas , Rudolf A. Treumann

We consider the stochastic background of gravitational waves produced during the radiation-dominated hot big bang as a constraint on the primordial density perturbation on comoving length scales much smaller than those directly probed by…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Hooshyar Assadullahi , David Wands

The generation of large-scale magnetic fields in inflationary cosmology is explored, in particular, in a kind of moduli inflation motivated by racetrack inflation in the context of the Type IIB string theory. In this model, the conformal…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Kazuharu Bamba

Cosmological hydrodynamical simulations of primordial star formation suggest that the gas within the first star-forming halos is turbulent. This has strong implications on the subsequent evolution, in particular on the generation of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Sharanya Sur , Dominik R. G. Schleicher , Robi Banerjee , Christoph Federrath , Ralf S. Klessen

Primordial magnetic fields (PMFs) are possible candidates for explaining the observed magnetic fields in galaxy clusters. Two competing scenarios of primordial magnetogenesis have been discussed in the literature: inflationary and…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-17 Salome Mtchedlidze , Paola Domínguez-Fernández , Xiaolong Du , Wolfram Schmidt , Axel Brandenburg , Jens Niemeyer , Tina Kahniashvili

Dark gauge fields have been discussed as candidates for dark matter recently. If they existed, primordial dark magnetic fields during inflation would have existed. It is believed that primordial gravitational waves (PGWs) arise out of…

High Energy Physics - Theory · Physics 2023-06-09 Sugumi Kanno , Ann Mukuno , Jiro Soda , Kazushige Ueda

The most studied mechanism of inflationary magnetogenesis relies on the time-dependence of the coefficient of the gauge kinetic term $F_{\mu\nu}\,{F}^{\mu\nu}$. Unfortunately, only extremely finely tuned versions of the model can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Chiara Caprini , Lorenzo Sorbo

Large scale magnetic fields represent a triple point where cosmology, high-energy physics and astrophysics meet for different but related purposes. After reviewing the implications of large scale magnetic fields in these different areas,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Massimo Giovannini

We present generic bounds on magnetic fields produced from cosmic inflation. By investigating field bounds on the vector potential, we constrain both the quantum mechanical production of magnetic fields and their classical growth in a model…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-10 Daniel Green , Takeshi Kobayashi

We present a new realization of the resonant production of primordial black holes as well as gravitational waves in a two-stage inflation model consisting of a scalar field \phi with an axion-monodromy-like periodic structure in the…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Zihan Zhou , Jie Jiang , Yi-Fu Cai , Misao Sasaki , Shi Pi

We study the instability of magnetic fields in a neutron star core driven by the parity violating part of the electron-nucleon interaction in the Standard Model. Assuming a seed field of the order $10^{12}\thinspace\text{G}$, that is a…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Maxim Dvornikov , Victor B. Semikoz

We explore a novel process in the early Universe in which thermalized photons are converted into gravitons in the presence of strong primordial magnetic fields. It is found that the frequency of generated gravitational waves (GWs) is…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-19 Tomohiro Fujita , Kohei Kamada , Yuichiro Nakai
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