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Related papers: Computation approach for CMB bispectrum from primo…

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Pursuing the original idea proposed in our previous paper (Paper I), we improve the method to determine the shape of the initial curvature perturbation spectrum $P(k)$ from the CMB data. The thickness of the last scattering surface (LSS)…

Astrophysics · Physics 2009-10-09 Makoto Matsumiya , Misao Sasaki , Jun'ichi Yokoyama

We calculate the cosmic microwave background (CMB) $B$-mode power spectrum resulting from anisotropic cosmic birefringence, without relying on the thin approximation of the last scattering surface. Specifically, we consider the influence of…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-04 Toshiya Namikawa

Primordial non-Gaussianity has set strong constraints on models of the early universe. Studies have shown that Loop Quantum Cosmology (LQC), which is an attempt to extend inflationary scenario to planck scales, leads to a strongly scale…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Roshna K , V. Sreenath

We examine the extent to which galactic and extragalactic foregrounds can hamper the detection of primordial Cosmic Microwave Background (CMB) anisotropies. We limit our discussion to intermediate angular scales, $10^{\prime}\lsim \theta…

Astrophysics · Physics 2009-09-25 L. Toffolatti

The Cosmic Microwave Background (CMB) is a relict of the early universe. Its perfect 2.725K blackbody spectrum demonstrates that the universe underwent a hot, ionized early phase; its anisotropy (about 80 \mu K rms) provides strong evidence…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Paolo de Bernardis , Silvia Masi

The primordial magnetic fields (PMFs) produced in the early universe are expected to be the origin of the large-scale cosmic magnetic fields. The PMFs are considered to leave a footprint on the cosmic microwave background (CMB) anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-17 Teppei Minoda , Kiyotomo Ichiki , Hiroyuki Tashiro

Magnetic fields appear wherever plasma and currents can be found. As such, they thread through all scales in Nature. It is natural, therefore, to suppose that magnetic fields might have been formed within the high temperature environments…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-16 Dai G. Yamazaki , Toshitaka Kajino , Grant J. Mathew , Kiyotomo Ichiki

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

In this talk I present a short review of primordial magnetic helicity effects on Cosmic Microwave Background (CMB) temperature and polarization anisotropies. These effects allow us to test for cosmological magnetic helicity, however, very…

Astrophysics · Physics 2009-11-13 Tina Kahniashvili

The cosmological birefringence caused by the coupling between the cosmic scalar field and the cosmic microwave background (CMB) photons through the Chern-Simons term can rotate the polarization planes of the photons, and mix the CMB E-mode…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Wen Zhao , Mingzhe Li

Weak lensing distortion of the background cosmic microwave background (CMB) temperature and polarization patterns by the foreground density fluctuations is well studied in the literature. We discuss the gravitational lensing modification to…

Astrophysics · Physics 2009-11-11 Chao Li , Asantha Cooray

The recent Cosmic Microwave Background (CMB) measurements indicate that there is power deficiency of the CMB anisotropies at large scales compared with the $\Lambda$CDM model. We have investigated the possibility of explaining such effects…

Astrophysics · Physics 2009-11-13 Rita Sinha , Tarun Souradeep

I discuss how parameters describing inflation in the very early universe may be related to primordial perturbation spectra. Precision observations of anisotropies in the cosmic microwave background (CMB) such as those provided by the WMAP…

Astrophysics · Physics 2015-06-24 David Wands

We consider a novel contribution to the polarization of the Cosmic Microwave Background induced by vector and tensor modes generated by the non-linear evolution of primordial scalar perturbations. Our calculation is based on relativistic…

Astrophysics · Physics 2009-11-10 Silvia Mollerach , Diego Harari , Sabino Matarrese

The changes in the cosmic microwave background (CMB) spectrum seen as an increase of temperature due to a strong magnetic field are determined and their influence on the polarization of the radiation is exhibited. The effect is due to the…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-24 Zofia Bialynicka-Birula , Iwo Bialynicki-Birula

We consider the hypothesis that nonlocal, omnidirectional, causally-coherent quantum entanglement of inflationary horizons may account for some well-known measured anomalies of Cosmic Microwave Background (CMB) anisotropy on large angular…

General Relativity and Quantum Cosmology · Physics 2022-02-16 Craig Hogan , Stephan S. Meyer

Measurements of the cosmic microwave background (CMB) radiation provide a unique opportunity for a direct study of the primordial cosmic plasma at redshift z ~1000. The angular power spectra of temperature and polarisation fluctuations are…

Astrophysics · Physics 2009-11-10 Marco Bersanelli , Davide Maino , Aniello Mennella

Measurement of Cosmic Microwave Background (CMB) temperature by Planck has resulted in extremely tight constraints on the $\Lambda$CDM model. However the data indicates a evidence of dipole modulated temperature fluctuations at large…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-06 Suvodip Mukherjee

We derive an expression for the non-Gaussian cosmic-microwave-background (CMB) statistic $I_l^3$ defined recently by Ferreira, Magueijo, and G\'orski in terms of the slow-roll-inflation parameters $\epsilon$ and $\eta$. This result shows…

Astrophysics · Physics 2011-02-02 Limin Wang , Marc Kamionkowski

Anisotropies in distortions to the frequency spectrum of the cosmic microwave background (CMB) can be created through spatially varying heating processes in the early Universe. For instance, the dissipation of small-scale acoustic modes…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Jens Chluba , Emanuela Dimastrogiovanni , Mustafa A. Amin , Marc Kamionkowski