Related papers: Superhorizon Perturbations and the Cosmic Microwav…
We investigate the Sunyaev-Zel'dovich (SZ) effect caused by primordial black holes (PBHs) on the cosmic microwave background (CMB) temperature fluctuations. The gas accreting on a PBH heats up by the release of the gravitational energy. As…
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…
In view of the growing tension between the dipole anisotropy of number counts of cosmologically distant sources and of the cosmic microwave background (CMB), we investigate the number count dipole induced by primordial perturbations with…
Thomson scattering of CMBR temperature anisotropies will cause the spectrum of the CMBR to differ from blackbody even when one resolves all anisotropies. A formalism for computing the anisotropic and inhomogeneous spectral distortions of…
Cosmic Microwave Background (CMB) experiments, such as WMAP and Planck, measure intensity anisotropies and build maps using a \emph{linearized} formula for relating them to the temperature blackbody fluctuations. However such a procedure…
Spatially fluctuating primordial magnetic fields (PMFs) inhomogeneously reheat the Universe when they dissipate deep inside the horizon before recombination. Such an energy injection turns into an additional photon temperature perturbation.…
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…
First, we establish which measures of large-scale perturbations are least afflicted by gauge artifacts and directly map the apparent evolution of inhomogeneities to local interactions of cosmological species. Considering nonlinear and…
The theoretical basis for the prediction of anisotropies in the cosmic microwave background is very well developed. Very low amplitude density and temperature perturbations produce small gravitational effects, leading to an anisotropy that…
Gravitational lensing, caused by matter perturbations along the line-of-sight to the last scattering surface, can modify the shape of the cosmic microwave background (CMB) anisotropy power spectrum. We discuss the detectability of lensing…
We propose a new mechanism of generating the $\mu$ distortion in cosmic microwave background (CMB) originated from primordial gravitational waves. Such $\mu$ distortion is generated by the damping of the temperature anisotropies through the…
In the context of cold dark matter (CDM) cosmological models, we have simulated images of the brightness temperature fluctuations in the cosmic microwave background (CMB)sky owing to the Sunyaev Zel$^{\prime}$dovich (S-Z) effect in a…
We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N)-theories. We point out a problem…
We discuss the nature of the possible high-l excess in the Cosmic Microwave Background (CMB) anisotropy power spectrum observed by the Cosmic Background Imager (CBI). We probe the angular structure of the excess in the CBI deep fields and…
In the context of inflationary scenarios, the observed large angle anisotropy of the Cosmic Microwave Background (CMB) temperature is believed to probe the primordial metric perturbations from inflation. Although the perturbations from…
We predict the level of small-scale anisotropy in the cosmic microwave background (CMB) due to the Sunyaev--Zel'dovich (SZ) effect for the ensemble of cosmological models that are consistent with current measurements of large-scale CMB…
We examine bounds on adiabatic and isocurvature density fluctuations from $\mu$-type spectral distortions of the cosmic microwave background (CMB). Studies of such distortion are complementary to CMB measurements of the spectral index and…
We derive cosmological parameters from the CBI measurements of the Cosmic Microwave Background (CMB) angular power spectrum. Our results provide an independent confirmation of the standard $\Omega_{\rm tot}=1$ $\Lambda$CDM model within the…
We study the effects on cosmic microwave background (CMB) temperature and polarization anisotropies of spatial fluctuations of the fine-structure parameter between causally disconnected regions of the Universe at the time of recombination.…
In a concordant $\Lambda$ Cold Dark Matter ($\Lambda$CDM) model, large-angle Cosmic Microwave Background (CMB) temperature anisotropy due to linear perturbations in the local universe is not negligible. We explore a possible role of an…