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Cosmic microwave background radiation can supply us some most significant parts of the information on the universe. Some researchers believe that The gravitational system cannot be decribed by the standard statistical mechanics. In this…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-03 Yang Liu

Cosmic Microwave Background (CMB) experiments, such as WMAP and Planck, measure intensity anisotropies and build maps using a linearized formula for relating them to the temperature blackbody fluctuations. However, this procedure also…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Alessio Notari , Miguel Quartin

Recently, it was shown that local variance maps of temperature anisotropy are simple and useful tools for the study of large scale hemispherical power asymmetry. This was done by studying the distribution of dipoles of the local variance…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-12 Saroj Adhikari

We present a complete set of formulae for calculating the bispectra of CMB temperature and polarization anisotropies generated from non-Gaussianity in the vector and tensor mode perturbations. In the all-sky analysis it is found that the…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-11 Maresuke Shiraishi , Shuichiro Yokoyama , Daisuke Nitta , Kiyotomo Ichiki , Keitaro Takahashi

We constrain deviations of the form $T\propto (1+z)^{1+\epsilon}$ from the standard redshift-temperature relation, corresponding to modifying distance duality as $D_L=(1+z)^{2(1+\epsilon)} D_A$. We consider a consistent model, in which both…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-28 Syksy Rasanen , Jussi Valiviita , Ville Kosonen

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

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce…

Astrophysics · Physics 2009-11-10 Simon Prunet , Jean-Philippe Uzan , Francis Bernardeau , Tristan Brunier

Mapping CMB polarization is an essential ingredient of current cosmological research. Particularly challenging is the measurement of an extremely weak B-mode polarization that can potentially yield unique insight on inflation. Achieving…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. Shimon , Y. Rephaeli , S. Sadeh , B. Keating

In the frame of a moving observer, the Cosmic Microwave Background (CMB) fluctuation exhibits violation of Statistical Isotropy (SI). The SI violation effect from our local motion on CMB temperature fluctuation has been measured in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-27 Suvodip Mukherjee , Aritra De , Tarun Souradeep

Parity violation found in the Cosmic Microwave Background (CMB) radiation is a crucial clue for the non-standard cosmological model or the possible contamination of various foreground residuals and/or calibration of the CMB data sets. In…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-22 P. Naselsky , W. Zhao , J. Kim , S. Chen

We perform an analysis of the CMB temperature data taken by the Planck satellite investigating if there is any significant deviation from cosmological isotropy. We look for differences in the spectrum between two opposite hemispheres and…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-14 Miguel Quartin , Alessio Notari

We study the imprints of anisotropic inflation on the CMB temperature fluctuations and polarizations. The statistical anisotropy stems not only from the direction dependence of curvature and tensor perturbations, but also from the cross…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-23 Masa-aki Watanabe , Sugumi Kanno , Jiro Soda

I review why we expect the CMB anisotropy to be polarized, what we can learn from studying polarization and the level of the experimental challenge it presents. A discussion of current and future polarization sensitive experiments will…

Astrophysics · Physics 2007-05-23 Martin White

We present new measurements of the power spectra of the E-mode of CMB polarization, the temperature T, the cross-correlation of E and T, and upper limits on the B-mode from 2.5 years of dedicated Cosmic Background Imager (CBI) observations.…

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

In single-field, slow-roll inflationary models, scalar and tensorial (Gaussian) perturbations are both characterized by a zero mean and a non-zero variance. In position space, the corresponding variance of those fields diverges in the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 I. Agullo , J. Navarro-Salas , Gonzalo J. Olmo , Leonard Parker

The recent BICEP2 detection of degree scale CMB B-mode polarization, coupled with a deficit of observed power in large angle temperature anisotropy, suggest that the slow-roll parameter $\epsilon_H$, the fractional variation in the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Wayne Hu

Precise measurements of the Cosmic Microwave Background (CMB) anisotropy have been one of the foremost concerns in modern cosmology as it provides valuable information on the cosmology of the universe. However, an accurate estimation of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-20 Fidy A. Ramamonjisoa , Subharthi Ray , Sanjit Mitra , Tarun Souradeep

The important studies of Peebles, and Bond and Efstathiou have led to the formula C_l = const/[l(l +1)] aimed at describing the lower order multipoles of the CMBR temperature variations caused by density perturbations with the flat…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. Dimitropoulos , L. P. Grishchuk
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