Related papers: Deviation from Gaussianity in the cosmic microwave…
We present a new, model-independent approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern. Our approach is based on the empirical distribution function of the normalized spherical harmonic…
Cosmological phase transitions in the primordial universe can produce anisotropic stochastic gravitational wave backgrounds (GWB), similar to the cosmic microwave background (CMB). For adiabatic perturbations, the fluctuations in GWB follow…
The Microwave Anisotropy Probe and Planck missions will provide low noise maps of the temperature of the cosmic microwave background (CMB). These maps will allow measurement of the power spectrum of the CMB with measurement noise below…
In this article, we extend previous studies based on CMB spherical harmonic phases (SHP) to examine the validity of the hypothesis that the temperature field of the CMB is consistent with a Gaussian random field (GRF). The null hypothesis…
The statistical expectation values of the temperature fluctuations of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. This assumption of {\em statistical isotropy} (SI) of the CMB anisotropy should…
The 21-cm brightness temperature fluctuation from the Dark Ages ($z \simeq 30-100$) will allow us to probe the inflationary epoch on very small scales ($>0.1 \, \mbox{Mpc}^{-1}$), inaccessible to cosmic microwave background experiments.…
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…
The improved data on the cosmic microwave background (CMB) anisotropy allow a better determination of the adiabaticity of the primordial perturbation. Interestingly, we find that recent CMB data seem to favor a contribution of a primordial…
We analyze the Cosmic Microwave Background (CMB) anisotropy data from the independent COBE FIRAS and DMR observations. We extract the frequency spectrum of the FIRAS signal that has the spatial distribution seen by DMR and show that it is…
Repeated studies of the CMB based on WMAP data have revealed an apparent asymmetry in the distribution of temperature fluctuations over the celestial sphere. The studies indicate that the amplitudes of temperature fluctuations are higher in…
Observations of the polarization of the cosmic microwave backround (CMB) have the potential to place much tighter constraints on cosmological parameters than observations of the fluctuations in temperature alone. We discuss using CMB…
We study inhomogeneities in the distribution of the excursion sets in the Cosmic Microwave Background (CMB) temperature maps obtained by the three years survey of the Wilkinson Microwave Anisotropy Probe (WMAP). At temperature thresholds…
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…
Current and upcoming high angular resolution and multi-frequency experiments are well poised to explore the rich landscape of secondary CMB anisotropies. In this context, we compute for the first time, the power spectrum of CMB fluctuations…
We develop a formalism for calculating cosmic microwave background (CMB) temperature and polarization anisotropies in cosmological models with Brans-Dicke gravity. We then modify publicly available Boltzmann codes to calculate numerically…
Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of…
Based on recent observations of the cosmic microwave background (CMB), claims of statistical anomalies in the properties of the CMB fluctuations have been made. Although the statistical significance of the anomalies remains only at the…
Upcoming cosmic microwave background (CMB) data can be used to explore harmonic 3-point functions that involve the B-mode component of the CMB polarization signal. We focus on bispectra describing the non-Gaussian correlation of the B-mode…
Inflationary cosmologies predict Gaussian primordial fluctuations, but subsequent gravitational lensing of the CMB disturbs its Gaussianity. Knowledge of the specific signature of lensing is necessary to distinguish a lensed Gaussian sky…
The phases of the Fourier transform of any linear cosmological perturbation may be random (the Gaussian case) or not (the non-Gaussian case). If a non-Gaussian inhomogeneity was generated during the inflationary era by some process of very…