English
Related papers

Related papers: Primordial magnetic fields: consistent initial con…

200 papers

In this paper we show that noncommutativity in spatial coordinates can generate magnetic field in the early Universe on a horizon scale. The strength of such a magnetic field depends on the number density of massive charged particles…

High Energy Physics - Phenomenology · Physics 2009-10-07 Anupam Mazumdar , Mohammad M. Sheikh-Jabbari

A primordial stochastic magnetic field will induce temperature and polarization fluctuations in the cosmic microwave background. We outline a calculation of the resulting fluctuation power spectra and present numerical results.

Astrophysics · Physics 2009-10-31 Tina Kahniashvili , Arthur Kosowsky , Andrew Mack , Ruth Durrer

A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contribution to the B-mode polarization power spectrum.…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Alex Zucca , Yun Li , Levon Pogosian

We describe a technique for using simulated tensor perturbations in order to place upper limits on the intensity of magnetic fields in the early universe. As an example, we apply this technique to the beginning of primordial…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-09 David Garrison

The Universe's initial conditions, in particular baryon and cold dark matter (CDM) isocurvature perturbations, are poorly constrained on sub-Mpc scales. In this paper, we develop a new formalism to compute the effect of small-scale baryon…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 Nanoom Lee , Yacine Ali-Haïmoud

Strongly supercooled first order phase transitions (FOPTs) can produce primordial black hole (PBH) dark matter (DM) along with observable gravitational waves (GWs) from bubble collisions. Such FOPTs may also produce coherent magnetic fields…

High Energy Physics - Phenomenology · Physics 2025-03-24 Shyam Balaji , Malcolm Fairbairn , Maria Olalla Olea-Romacho

There is a large and growing interest in observations of small-scale structure in dark matter. We propose a new way to probe dark matter structures in the $\sim 10 - 10^8 \, M_\odot$ range. This allows us to constrain the primordial power…

High Energy Physics - Phenomenology · Physics 2024-10-17 Peter W. Graham , Harikrishnan Ramani

We study the constraints on primordial magnetic fields (PMFs) in light of the global 21-cm signal observed during the dark ages. Primordial magnetic fields can heat the intergalactic medium (IGM) via magnetohydrodynamic effects. We…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-03 Vivekanand Mohapatra , Pravin Kumar Natwariya , Alekha C. Nayak

In this contribution we will shortly review the main mechanism through which primordial magnetic fields may affect the electroweak baryogenesis. It is shown that although strong magnetic fields might enhance the strength of the electroweak…

High Energy Physics - Phenomenology · Physics 2016-11-03 Dario Grasso

(abridged) We suggest here that the large scale fields $\sim \mu$G, observed in galaxies at both high and low redshifts by Faraday Rotation Measurements (FRMs), have their origin in the electromagnetic fluctuations that naturally occurred…

Astrophysics · Physics 2008-11-26 Rafael S. de Souza , Reuven Opher

Primordial magnetic fields (PMFs) create a large squeezed-type non-Gaussianity in tensor perturbation, which generates non-Gaussian temperature fluctuations in the cosmic microwave background (CMB). We for the first time derive an…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-13 Maresuke Shiraishi , Toyokazu Sekiguchi

In this work we study the possibility that primordial magnetic fields observed in galaxies could be produced by a dark matter halo made of charged ultra-light bosons. In the model, we assume that ultra-light bosons arise as excitations of a…

General Relativity and Quantum Cosmology · Physics 2019-10-23 M. Hernandez , A. Avilez-Lopez , T. Matos

We study the implications of primordial magnetic fields for the thermal and ionization history of the post-recombination era. In particular we compute the effects of dissipation of primordial magnetic fields owing to ambipolar diffusion and…

Astrophysics · Physics 2009-11-13 Shiv K Sethi , Biman B. Nath , Kandaswamy Subramanian

The origin of large scale magnetic fields is one of the most puzzling topics in cosmology and astrophysics. It is assumed that the observed magnetic fields result from the amplification of an initial field produced in the early universe. In…

General Relativity and Quantum Cosmology · Physics 2014-12-18 Hector J. Hortua , Leonardo Castañeda

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

Primakoff effect offers us with a way to determine the radiative decay width of pseudo-scalar mesons when they are photo-produced in the electromagnetic field of hadronic systems. Taking advantage of recent developments in the Regge…

High Energy Physics - Phenomenology · Physics 2014-11-18 J. M. Laget

Primordial magnetic fields and massive neutrinos can leave an interesting signal in the CMB temperature and polarization. We perform a systematic analysis of general perturbations in the radiation-dominated universe, accounting for any…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 J. Richard Shaw , Antony Lewis

Primordial black holes (PBHs) could provide the dark matter in various mass windows below $10^2 M_{\odot}$ and those of $30 M_{\odot}$ might explain the LIGO events. PBHs much larger than this might have important consequences even if they…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-26 Bernard Carr , Joseph Silk

In view of several conflicting results, we reanalyze the effects of magnetic fields on the primordial nucleosynthesis. In the case the magnetic field is homogeneous over a horizon volume, we show that the main effects of the magnetic field…

Astrophysics · Physics 2008-11-26 D. Grasso , H. R. Rubinstein

We present cosmological dark matter (DM)--only zoom-in simulations of a Milky Way analog originating from enhanced linear matter power spectra $P(k)$ relative to the standard cold, collisionless DM (CDM) cosmology. We consider a Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-23 Ethan O. Nadler , Vera Gluscevic , Andrew Benson