English
Related papers

Related papers: Constraining Primordial Magnetism

200 papers

We use the cosmic microwave background temperature anisotropy to place limits on large-scale magnetic fields in an inhomogeneous (perturbed Friedmann) universe. If no assumptions are made about the spacetime geometry, only a weak limit can…

Astrophysics · Physics 2017-08-23 C. A. Clarkson , A. A. Coley , R. Maartens , C. G. Tsagas

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

The effects of magnetic fields on Big Bang Nucleosynthesis(BBN) have been calculated, and the impact on the abundances of the light elements have been investigated numerically. An upper limit on the strength of primordial magnetic fields…

Astrophysics · Physics 2009-12-30 Baolian Cheng , David N. Schramm , James W. Truran

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

Primordial magnetic fields (PMF) can create polarization $B$-modes in the cosmic microwave background (CMB) through Faraday rotation (FR), leading to non-trivial 2-point and 4-point correlators of the CMB temperature and polarization. We…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Amit P. S. Yadav , Levon Pogosian , Tanmay Vachaspati

Upcoming measurements of the small-scale primary cosmic microwave background (CMB) temperature and polarization power spectra ($TT$/$TE$/$EE$) are anticipated to yield transformative constraints on new physics, including the effective…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-26 Fiona McCarthy , J. Colin Hill , Mathew S. Madhavacheril

The presence of magnetic fields in the early universe affects the cosmological processes, leading to the distinct signature, which allows constraining their properties and the genesis mechanisms. In this study, we revisit the method to…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-13 Ashu Kushwaha , Teruaki Suyama

Small scale CMB angular power spectrum contains not only primordial CMB information but also many contaminants coming from secondary anisotropies. Most of the latter depend on the cosmological model but are often marginalised over. We…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Marian Douspis , Laura Salvati , Adélie Gorce , Nabila Aghanim

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

The enormous red-shifting of the modes during the inflationary epoch suggests that physics at the very high energy scales may modify the primordial perturbation spectrum. Therefore, the measurements of the anisotropies in the Cosmic…

High Energy Physics - Theory · Physics 2015-06-26 S. Shankaranarayanan , L. Sriramkumar

Was the primordial universe magnetized? The answer to this question would help explain the origin of micro-Gauss strength magnetic fields observed in galaxies. It is also of fundamental importance in developing a complete theory of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-14 Levon Pogosian , Alex Zucca

Magnetic fields are present on all scales in the Universe. While we understand the processes which amplify the fields fairly well, we do not have a "natural" mechanism to generate the small initial seed fields. By using fully relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-18 Ellie Nalson , Adam J. Christopherson , Karim A. Malik

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

Primordial magnetic fields generated in the early universe are subject of considerable investigation, and observational limits on their strength are required to constrain the theory. Due to their impact on the reionization process, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Dominik R. G. Schleicher , Francesco Miniati

CMB observations provide a precise measurement of the primordial power spectrum on large scales, corresponding to wavenumbers $10^{-3}$ Mpc$^{-1}$ < k < 0.1 Mpc$^{-1}$, [1-8]. Luminous red galaxies and galaxy clusters probe the matter power…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-24 Razieh Emami , George Smoot

Recent cosmological data and astrophysical observations, such as the Hubble tension and the increasing preference from galaxy surveys for dynamical dark energy, have begun to challenge the standard $\Lambda$-cold dark matter cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-23 Jonathan Schiff , Tejaswi Venumadhav

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

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

If the seed magnetic fields exist in the early Universe, tensor components of their anisotropic stresses are not compensated prior to neutrino decoupling and the tensor metric perturbations generated from them survive passively.…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-10 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

Using the full radiation transfer function, we numerically calculate the CMB angular bispectrum seeded by the compensated magnetic scalar density mode. We find that, for the string inspired primordial magnetic fields characterized by index…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Rong-Gen Cai , Bin Hu , Hong-Bo Zhang