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相关论文: A Calculation of Cosmic Variance in Cosmic Microwa…

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Anisotropies in the cosmic microwave background radiation due to gravity waves are investigated. An initial spectrum of gravity waves may have been induced during an epoch of inflation. We study the propagation of such a spectrum in a…

天体物理学 · 物理学 2008-02-03 Ruth Durrer , Tina Kahniashvili

We present an in depth discussion of the production of gravitational waves from an inflationary phase that could have occurred in the early universe, giving derivations for the resulting spectrum and energy density. We also consider the…

高能物理 - 唯象学 · 物理学 2016-09-01 Martin White

Cosmic Microwave Background (CMB) anisotropies that result from quantum fluctuations during inflation are explored and the impact of their ``cosmic variance'' on the ability to use existing data to probe inflationary models is studied. We…

天体物理学 · 物理学 2016-08-30 Martin White , Lawrence M. Krauss , Joseph Silk

We asses the contribution to the observed large scale anisotropy of the cosmic microwave background radiation, arising from both gravity waves as well as adiabatic density perturbations, generated by a common inflationary mechanism in the…

高能物理 - 唯象学 · 物理学 2009-10-22 Tarun Souradeep , Varun Sahni

We discuss the influence of gravitational waves (GWs) upon the polarisation of the Cosmic Microwave Background Radiation (CMBR). We show how to compute the {\em rms} temperature anisotropy and polarisation of the CMBR induced by GWs of…

天体物理学 · 物理学 2016-06-08 R. A. Frewin , A. G. Polnarev , P. Coles

Non-linear evolution of cosmological energy density fluctuations triggers deviations from Gaussianity in the temperature distribution of the cosmic microwave background. A method to estimate these deviations is proposed. N-body simulations…

天体物理学 · 物理学 2009-11-07 A. M. Aliaga , V. Quilis , J. V. Arnau , D. Saez

We calculate the large scale polarization of the cosmic microwave background induced by the anisotropy of the spatial geometry of our universe. Assuming an eccentricity at decoupling of about $0.64 10^{-2}$, we find $\Delta T_{pol}/ T_0…

天体物理学 · 物理学 2007-10-24 Paolo Cea

The primary results of most observations of cosmic microwave background (CMB) anisotropy are estimates of the angular power spectrum averaged through some broad band, called band-powers. These estimates are in turn what are used to produce…

天体物理学 · 物理学 2016-08-25 Lloyd Knox

We derive the primordial power spectrum of density fluctuations in the framework of quantum cosmology. For this purpose we perform a Born-Oppenheimer approximation to the Wheeler-DeWitt equation for an inflationary universe with a scalar…

广义相对论与量子宇宙学 · 物理学 2012-01-17 Claus Kiefer , Manuel Kraemer

We investigate a statistical anisotropy on the Cosmic Microwave Background (CMB) bispectrum, which can be generated from the primordial non-Gaussianity induced by quantum fluctuations of a vector field. We find new configurations in the…

宇宙学与河外天体物理 · 物理学 2011-12-03 Maresuke Shiraishi , Shuichiro Yokoyama

Inflation gives rise to a nearly scale-invariant spectrum of tensor perturbations (gravitational waves), their contribution to the Cosmic Background Radiation (CBR) anisotropy depends upon the present cosmological parameters as well as…

天体物理学 · 物理学 2014-10-13 Michael S. Turner , Yun Wang

The analysis of anisotropies in the cosmic microwave background (CMB) has become an extremely valuable tool for cosmology. We even have hopes that planned CMB anisotropy experiments may revolutionize cosmology. Together with determinations…

天体物理学 · 物理学 2011-04-15 Ruth Durrer

We study the possible contribution of a stochastic gravitational wave background to the anisotropy of the cosmic microwave background (CMB) in cold and mixed dark matter (CDM and MDM) models. We test this contribution against recent…

天体物理学 · 物理学 2009-10-31 A. Melchiorri , M. V. Sazhin , V. V. Shulga , N. Vittorio

The effect of gravitational lensing on cosmic microwave background (CMB) anisotropies is investigated using the power spectrum approach. The lensing effect can be calculated in any cosmological model by specifying the evolution of…

天体物理学 · 物理学 2009-10-28 Uros Seljak

A conventional explanation of the dipole anisotropy of the cosmic microwave background (CMB) radiation is in terms of the Doppler effect: our galaxy is moving with respect to CMB frame with $ \sim 600 ~ km ~ s^{-1} $. However, as the deep…

天体物理学 · 物理学 2007-05-23 M. Jaroszynski , B. Paczynski

Recent measurements of the Cosmic Microwave Background Anisotropy have provided evidence for the presence of oscillations in the angular power spectrum. These oscillations are a wonderful confirmation of the standard cosmological scenario…

天体物理学 · 物理学 2007-05-23 Alessandro Melchiorri

Long-wavelength gravitational waves can induce significant temperature anisotropy in the cosmic microwave background. Distinguishing this from anisotropy induced by energy density fluctuations is critical for testing inflationary cosmology…

天体物理学 · 物理学 2009-09-25 R. Crittenden , J. R. Bond , R. L. Davis , G. Efstathiou , P. J. Steinhardt

We present a 1+3 covariant discussion of the contribution of gravitational waves to the anisotropy of the CMB in an almost-Friedmann-Robertson-Walker universe. Our discussion is based in the covariant approach to perturbations in cosmology,…

天体物理学 · 物理学 2014-10-13 Anthony Challinor

We study scalar mode perturbations (magnetosonic waves) induced by a helical stochastic cosmological magnetic field and derive analytically the corresponding cosmic microwave background (CMB) temperature and polarization anisotropy angular…

天体物理学 · 物理学 2008-11-26 Tina Kahniashvili , Bharat Ratra

We study the inflation process of universe based on the renormalizable quantum gravity formulated as a conformal field theory (CFT). We show that the power-law CFT spectrum approaches to that of the Harrison-Zel'dovich-Peebles type as the…

宇宙学与河外天体物理 · 物理学 2010-05-18 Ken-ji Hamada , Shinichi Horata , Tetsuyuki Yukawa
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