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Primordial magnetic fields (PMFs), being present before the epoch of cosmic recombination, induce small-scale baryonic density fluctuations. These inhomogeneities lead to an inhomogeneous recombination process that alters the peaks and…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 Karsten Jedamzik , Andrey Saveliev

Parity-violating extensions of Maxwell electromagnetism induce a rotation of the linear polarization plane of photons during propagation. This effect, known as cosmic birefringence, impacts on the Cosmic Microwave Background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-18 Alessandro Greco , Nicola Bartolo , Alessandro Gruppuso

Primordial magnetic fields will generate non-Gaussian signals in the cosmic microwave background (CMB) as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. We compute a new measure of…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-15 Pranjal Trivedi , T. R. Seshadri , Kandaswamy Subramanian

We constrain a stochastic background of primordial magnetic field (PMF) by its contribution to the angular power spectrum of cosmic microwave background anisotropies. We parametrize such stochastic background by a power-law spectrum with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Daniela Paoletti , Fabio Finelli

The primordial magnetic field (PMF) can strongly affect the cosmic microwave background (CMB) power spectrum and the formation of large scale structure. In this presentation, we calculate the CMB temperature anisotropies generated by…

Astrophysics · Physics 2008-11-26 Dai G. Yamazaki , Kiyotomo Ichiki , Toshitaka Kajino , Grant J. Mathews

Magnetic fields are everywhere in nature and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-22 Dai G. Yamazaki , Kiyotomo Ichiki , Toshitaka Kajino , Grant J. Mathew

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

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

Recent measurements of the galaxy 4-Point Correlation Function (4PCF) have seemingly detected non-zero parity-odd modes at high significance. Since gravity, the primary driver of galaxy formation and evolution is parity-even, any parity…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-26 Matthew Reinhard , Zachary Slepian , Jiamin Hou , Alessandro Greco

Primordial Magnetic Fields (PMFs) -- magnetic fields originating in the early Universe and permeating the cosmological scales today -- can explain the observed microGauss-level magnetisation of galaxies and their clusters. In light of…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-29 Salome Mtchedlidze , Franco Vazza , Xiaolong Du , Ettore Carretti , Chiara Stuardi , Shane Patrick O'Sullivan

Parity-odd four-point correlation functions, or trispectra, of cosmic matter density fields provide a unique probe of fundamental symmetries in cosmology. Trispectra of primordial matter density fluctuations produced in the early universe…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-08 Sha Azyzy , Drew Jamieson , Eiichiro Komatsu , Toshiki Kurita

The origin of the $\mu$G magnetic fields observed in galaxies is unknown. One promising scenario is that magnetic fields generated during inflation, larger than 0.1 nG on Mpc scales, were adiabatically compressed to $\mu$G strengths in…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Sayan Mandal , Neelima Sehgal , Toshiya Namikawa

Parity-violation leaves tell-tale trails in many cosmological observables. We illustrate parity-odd primordial scalar trispectra, that despite being of modest strength, impart detectable chirality to scalar-induced gravitational waves…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-08 H. V. Ragavendra , Nicola Bartolo

Primordial magnetic fields (PMFs) can enhance matter power spectrum on small scales ($\lesssim$ Mpc) and still agree with bounds from cosmic microwave background (CMB) and Faraday rotation measurements. As modes on scales smaller than Mpc…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 Pranjal Ralegankar , Mak Pavičević , Matteo Viel

We investigate the impact of a stochastic background of Primordial Magnetic Fields (PMF) generated before recombination on the ionization history of the Universe and on the Cosmic Microwave Background radiation (CMB). Pre-recombination PMFs…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-28 D. Paoletti , J. Chluba , F. Finelli , J. A. Rubino-Martin

The origin of astrophysical magnetic fields observed in galaxies and clusters of galaxies is still unclear. One possibility is that primordial magnetic fields generated in the early Universe provide seeds that grow through compression and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 C. Fedeli , L. Moscardini

We study the reconstruction of the cosmic rotation power spectrum produced by parity-violating physics, with an eye to ongoing and near future cosmic microwave background (CMB) experiments such as BICEP Array, CMBS4, LiteBIRD and Simons…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-27 Toshiya Namikawa

We investigate parity-violating signatures of temperature and polarization bispectra of the cosmic microwave background (CMB) in an inflationary model where a rolling pseudoscalar produces large equilateral tensor non-Gaussianity. By a…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 Maresuke Shiraishi , Angelo Ricciardone , Shohei Saga

Possible existence of the primordial magnetic fields has affected the structure formation of the universe. In this paper it is shown that the initial conditions for density perturbations with magnetic fields derived in previous works are…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-20 Kazuhiko Kojima , Kiyotomo Ichiki

Cosmological magnetic fields induce temperature and polarization fluctuations in the cosmic microwave background (CMB) radiation. A cosmological magnetic field with current amplitude of order $10^{-9}$ G is detectable via observations of…

Astrophysics · Physics 2009-11-10 Tina Kahniashvili , Bharat Ratra , ;