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The aberration and Doppler coupling effects of the Cosmic Microwave Background (CMB) were recently measured by the Planck satellite. The most straightforward interpretation leads to a direct detection of our peculiar velocity $\beta$,…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-14 Omar Roldan , Alessio Notari , Miguel Quartin

The cosmic microwave background (CMB) temperature anisotropies exhibit a large-scale dipolar power asymmetry. To determine whether this is due to a real, physical modulation or is simply a large statistical fluctuation requires the…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 D. Contreras , J. P. Zibin , D. Scott , A. J. Banday , K. M. Górski

Future Cosmic Microwave Background (CMB) experiments will deliver extremely accurate measurements of the E-modes pattern of the CMB polarization field. Given the sharpness of the E-modes transfer functions, such surveys make for a powerful…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Matteo Braglia , Xingang Chen , Dhiraj Kumar Hazra , Lucas Pinol

Distortions in the primordial cosmic microwave background (CMB) along the line-of-sight can be modeled and described using 11 fields. These distortion fields correspond to various cosmological signals such as weak gravitational lensing of…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Amit P. S. Yadav , Meng Su , Matias Zaldarriaga

We present an all-sky formalism for the Cosmic Microwave Background (CMB) bispectrum induced by the primordial non-Gaussianities not only in scalar but also in vector and tensor fluctuations. We find that the bispectrum can be formed in an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

In forthcoming years, connections between cosmology and particle physics will be made increasingly important with the advent of a new generation of cosmic microwave background (CMB) experiments. Here, we review a number of these links. Our…

Astrophysics · Physics 2008-11-26 Marc Kamionkowski , Arthur Kosowsky

A primordial cosmic microwave background B-mode is widely considered a "smoking gun" signature of an early period of inflationary expansion. However, competing theories of the origin of structure, including string gases and bouncing…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-11 Brian A. Powell

The BICEP2 collaboration reports a detection of primordial cosmic microwave background (CMB) B-mode with a tensor-scalar ratio $r=0.20^{+0.07}_{-0.05}$ (68% C.L.). However, this result is in tension with the recent Planck limit, $r<0.11$…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-30 Jun-Qing Xia , Yi-Fu Cai , Hong Li , Xinmin Zhang

The BICEP2 collaboration reported recently a B-mode polarization of the cosmic microwave background (CMB) radiation inconsistent with the null hypothesis at a significance of > 5 {\sigma}. This result has been often interpreted as a…

General Physics · Physics 2014-08-28 Luis Gonzalez-Mestres

In this work we investigate the effects of the primordial magnetic fields on cosmic microwave background anisotropies (CMB). Based on cosmological magnetohydrodynamic (MHD) simulations we calculate the CMB anisotropy spectra and…

Astrophysics · Physics 2009-11-13 Hiroyuki Tashiro , Naoshi Sugiyama , Robi Banerjee

In standard inflationary cosmology, scalar and tensor perturbations grew as the Universe expanded and froze when their wavelengths exceeded the Hubble horizon, producing a tell-tale signature in the fluctuation spectrum and amplitude of the…

General Relativity and Quantum Cosmology · Physics 2023-07-21 Fulvio Melia

We investigate the degree to which the Cosmic Microwave Background (CMB) can be used to constrain primordial non-Gaussianity coming from the presence of spinning particles coupled to the inflaton. We compute the $\langle TTT \rangle$ and…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-09 Lorenzo Bordin , Giovanni Cabass

The cosmic microwave background (CMB) offers a unique window into the early universe, providing insights into cosmological parameters like the Hubble constant. Recent precise measurements of the CMB by experiments like Planck seem to point…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-26 Pablo Lemos , Paul Shah

We review aspects of Cosmic Microwave Background (CMB) spectral distortions which do not appear to have been fully explored in the literature. In particular, implications of recent evidences of heating of the intergalactic medium (IGM) by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 G. De Zotti , M. Negrello , G. Castex , A. Lapi , M. Bonato

We present a new and especially powerful signature of cosmic strings and other topological or non-topological defects in the polarization of the cosmic microwave background (CMB). We show that even if defects contribute 1% or less in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Juan Garcia-Bellido , Ruth Durrer , Elisa Fenu , Daniel G. Figueroa , Martin Kunz

The magneto-hydrodynamic decay of primordial magnetic fields can distort the black-body spectrum of the cosmic microwave background (CMB) by draining magnetic energy into thermal plasmas and photons. The current limits on CMB distortion…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-24 Fumio Uchida , Kohei Kamada , Hiroyuki Tashiro

We study the imprint of a coupling of scalar dark energy to photon on the cosmic microwave background (CMB) polarization. The time-evolving field value as well as the perturbation of the scalar generically induce $B$-mode polarization.…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 Seokcheon Lee , Guo-Chin Liu , Kin-Wang Ng

If the B-mode signal in the CMB polarization seen by the BICEP2 experiment is confirmed, it has dramatic implications for models of inflation. The result is also in tension with Planck limits on standard inflationary models. It is therefore…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-20 Camille Bonvin , Ruth Durrer , Roy Maartens

We investigate the potential of observations of anisotropies in the cosmic microwave background (CMB) and large-scale structure in the Universe to detect possible modifications of standard inflationary models by physics beyond the Planck…

Astrophysics · Physics 2009-11-10 Oystein Elgaroy , Steen Hannestad

In this work we study the imprints of a primordial cosmic string on inflationary power spectrum. Cosmic string induces two distinct contributions on curvature perturbations power spectrum. The first type of correction respects the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Sadra Jazayeri , Alireza Vafaei Sadr , Hassan Firouzjahi