Related papers: Scalar-tensor correlations and large-scale power s…
Many analyses of microwave background experiments neglect the correlation of noise in different frequency or polarization channels. We show that these correlations, should they be present, can lead to severe misinterpretation of an…
In inflationary models with minimal amount of gravity waves, the primordial power spectrum of density fluctuations, $A_S^2(k)$, together with the basic cosmological parameters, completely specify the predictions for the cosmic microwave…
We discuss the cosmological implications of the new constraints on the power spectrum of the Cosmic Microwave Background Anisotropy derived from a new high resolution analysis of the MAXIMA-1 measurement (Lee et al. 2001). The power…
We demonstrate that the cosmic microwave background (CMB) temperature-polarization cross-correlation provides accurate and robust constraints on cosmological parameters. We compare them with the results from temperature or polarization and…
Recent Wilkinson Microwave Anisotropy Probe (WMAP) data confirm the Cosmic Microwave Background (CMB) quadrupole anomaly. We further elaborate our previous proposal that the quadrupole power can be naturally suppressed in axis-symmetric…
We reexamine the temperature-polarization correlation function of the cosmic microwave background induced by tensor mode with a scale-invariant spectrum in reionized standard cold dark matter models. It is found that the sign of the…
This thesis is centered on three main subjects within the theory of inflation and cosmological perturbations: loop corrections to the power spectrum of curvature fluctuations generated during inflation; evolution of cosmological…
We recently derived exact solutions for the scalar, vector and tensor mode functions of a single, minimally coupled scalar plus gravity in an arbitrary homogeneous and isotropic background. These solutions are applied to obtain improved…
As repeatedly speculated in the past, the linear polarization of the Cosmic Microwave Background can be rotated via the Faraday effect. An economic explanation of the recent Bicep2 observations, not relying on long-wavelength tensor modes…
We apply our symmetry based Power tensor technique to test conformity of PLANCK Polarization maps with statistical isotropy. On a wide range of angular scales (l=40-150), our preliminary analysis detects many statistically anisotropic…
We find several missing one-loop-order contributions in previous considerations about secondary gravitational waves induced at nonlinear order in cosmological perturbations. We consider a consistent perturbative expansion to third-order in…
We investigate a possibility of constraining statistical anisotropies of the primordial tensor perturbations by using future observations for the Cosmic Microwave Background (CMB) B-mode polarization. By parameterizing a…
Primordial gravitational waves could be non-Gaussian, just like primordial scalar perturbations. Although the tensor two-point function has thus-far remained elusive, the three-point function could, in principle, be large enough to be…
We study the eigenmodes of the spin-2 Laplacian in orientable Euclidean manifolds and their implications for the tensor-induced part of the cosmic microwave background (CMB) temperature and polarization anisotropies. We provide analytic…
We investigate the possibility that a heavy scalar field, whose mass exceeds the Hubble scale during inflation, could leave non-negligible signatures in the Cosmic Microwave Background (CMB) temperature anisotropy power spectrum through the…
The angular power spectrum of the cosmic microwave background temperature anisotropy observed by WMAP has an anomalous dip at l~20 and bump at l~40. One explanation for this structure is the presence of features in the primordial curvature…
We investigate the ability to constrain oscillatory features in the primordial power spectrum using current and future cosmic microwave background observations. In particular, we study the observability of an oscillation arising from…
We investigate stellar core collapse in scalar-tensor theory with a massive self-interacting scalar field. In these theories, strong long-lived inverse chirp signals could be induced during the stellar core collapse, which provides us with…
We present the first attempt to use a combination of CMB, LIGO, and PPTA data to constrain both the tilt and the running of primordial tensor power spectrum through constraints on the gravitational wave energy density generated in the early…
Spectral distortions of the cosmic microwave background (CMB) may become a powerful probe of primordial perturbations at small scales. Existing studies of spectral distortions focus almost exclusively on primordial scalar metric…