相关论文: DT/T beyond linear theory
Cosmological inhomogeneities gravitationally deflect radiation propagating from distant sources, transforming the spatial and angular correlation functions of intrinsic source properties. For a gaussian distribution of deflections (e.g.…
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…
We discuss the photoionization of the intergalactic medium by early formed quasars and propose a mechanism which could generate measurable temperature fluctuations $\delta_{T }~=~\Delta T/T$ of the cosmic microwave background (CMB). Early…
We study the kinematic Sunyaev-Zel'dovich (kSZ) effect in a Lem\^itre-Tolman-Bondi (LTB) universe model whose distance-redshift relation agrees with that of the concordance $\Lambda$CDM model at redshifts $z\lesssim2$. This LTB universe…
We discuss how an extended foreground of the cosmic microwave background (CMB) can account for the anomalies in the low multipoles of the CMB anisotropies. The distortion needed to account for the anomalies is consistent with a cold spot…
Tangled, primordial cosmic magnetic fields create small rotational velocity perturbations on the last scattering surface (LSS) of the cosmic microwave background radiation (CMBR). Such perturbations can contribute significantly to the CMBR…
We investigate the contribution of cosmic string loops to the Cosmic Microwave Background (CMB) anisotropies. This is done by extending the Unconnected Segment Model (USM) to include the contribution of the cosmic string loops created…
Weak lensing distortion of the background cosmic microwave background (CMB) temperature and polarization patterns by the foreground density fluctuations is well studied in the literature. We discuss the gravitational lensing modification to…
We study the evolution of curvature perturbations and the cosmic microwave background (CMB) power spectrum in the presence of an hypothesized extra anisotropic stress which might arise, for example, from the dark radiation term in…
We investigate the effect of gravitational lensing, produced by linear density perturbations, for anisotropies of the Cosmic Background Radiation (CBR) on scales of arcminutes. In calculations, a flat universe ($\Omega=1$) and the…
Measurements of the Cosmic Microwave Background (CMB) temperature anisotropies on large angular scales have uncovered a number of anomalous features of marginal statistical significance, such as a hemispherical power asymmetry, lack of…
Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…
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…
The anisotropies of the cosmic microwave background (CMB) are computed for the half-turn space E_2 which represents a compact flat model of the Universe, i.e. one with finite volume. This model is inhomogeneous in the sense that the…
Damping of primordial gravitational waves due to the anisotropic stress contribution owing to the cosmological neutrino background (C$\nu$B) is investigated in the context of a radiation-to-matter dominated Universe. Besides its inherent…
We estimate the level of confusion to Cosmic Microwave Background anisotropy measurements caused by extragalactic infrared sources. CMB anisotropy observations at high resolution and high frequencies are especially sensitive to this…
Large-scale magnetic fields affect the scalar modes of the geometry whose ultimate effect is to determine the anisotropies of the Cosmic Microwave Background (CMB in what follows). For the first time, a consistent numerical approach to the…
The full sky measurements of the Cosmic Microwave Background (CMB) temperature anisotropies by $\textit{WMAP}$ and $\textit{Planck}$ have highlighted the presence of several unexpected isotropy-breaking features on the largest angular…
We have computed an estimate of the angular power spectrum of the Cosmic Microwave Background (CMB) induced by cosmic strings on angular scales $>~ 15'$, using a numerical simulation of a cosmic string network; and decomposed this pattern…
Several accurate analyses have revealed a statistically significant North-South ecliptic asymmetry in the large-angle correlations strength of the Cosmic Microwave Background (CMB) radiation temperature field data from the Wilkinson…