Related papers: Large Angle CMB Fluctuations from Cosmic Strings w…
We study dependence of the CMB temperature anisotropy spectrum on the value of the fine structure constant $\alpha$ and the equation of state of the dark energy component of the total density of the universe. We find that bounds imposed on…
Within two specific string cosmology scenarios --differing in the way the pre- and post-big bang phases are joined-- we compute the size and spectral slope of various types of cosmologically amplified quantum fluctuations that arise in…
The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Universe ($\Omega$), the baryon density, the Hubble constant ($h$),…
Cosmic strings are topological defects possibly formed in the early Universe, which may be observable due to their gravitational effects on the cosmic microwave background radiation or gravitational wave experiments. To this effect it is…
We investigate the potential of observations of anisotropies in the cosmic microwave background (CMB) and large-scale structure in the Universe to detect possible modifications of standard inflationary models by physics beyond the Planck…
We report on a calculation of large scale anisotropy in the cosmic microwave background radiation in the global monopole and texture models for cosmic structure formation. We have evolved the six component linear gravitational field along…
The COBE satellite's maps of the cosmic microwave background (CMB) anisotropy do not have the resolution to discriminate between theories of cosmic structure formation based on inflation, and those based on field ordering following a…
String models can produce successful inflationary scenarios in the context of brane collisions and in many of these models cosmic strings may also be produced. In scenarios such as KKLMMT the string contribution is naturally predicted to be…
We present a cosmic string on a warped five dimensional space time in Einstein-Yang-Mills theory. Four-dimensional cosmic strings show some serious problems concerning the mechanism of string smoothing related to the string mass per unit…
New measurements of galaxy clustering and background radiations provide improved constraints on the isotropy and homogeneity of the Universe on large scales. In particular, the angular distribution of radio sources and the X-Ray Background…
We study the effect of global topology of the spatial geometry on the cosmic microwave background (CMB) for closed flat and closed hyperbolic models in which the spatial hypersurface is multiply connected. If the CMB temperature…
We use observational data on the large scale structure (LSS) of the Universe measured over a wide range of scales from sub-galactic up to horizon scale and on the cosmic microwave background anisotropies to determine cosmological parameters…
We review how the various large-scale data constrain cosmological parameters and, consequently, theories for the origin of large-scale structure in the Universe. We discuss the form of the power spectrum implied by the correlation data of…
We report a search for signatures of cosmic strings in the the Cosmic Microwave Background data from the Wilkinson Microwave Anisotropy Probe. We used a digital filter designed to search for individual cosmic strings and found no evidence…
An analysis of cosmological models in spatially flat Friedmann Universe with cosmic gravitational wave background and zero $\Lambda$-term is presented. The number of free parameters is equal to 5, they are $\sigma_8$, $n$, $\Omega_\nu$,…
( to appear in: Proceedings of the Nishonomiya Yukawa Memorial Symposium Edited by M. Sasaki) There are several models for generating fluctuations in an open universe that are compatible with the microwave background fluctuations detected…
Because cosmic superstrings generically form junctions and gauge theoretic strings typically do not, junctions may provide a signature to distinguish between cosmic superstrings and gauge theoretic cosmic strings. In cosmic microwave…
Overall, brane inflation is compatible with the recent analysis of the WMAP data. Here we explore the constraints of WMAP and 2dFGRS data on the various brane inflationary scenarios. Brane inflation naturally ends with the production of…
We compare various physically different measurements of linear matter density perturbation amplitude, $sigma_8$, which are obtained from the observations of CMB anisotropy, galaxy cluster mass function, weak gravitation lensing, matter…
We study the Cosmic Microwave Background (CMB) anisotropies produced by cosine-type quintessence models. In our analysis, effects of the adiabatic and isocurvature fluctuations are both taken into account. For purely adiabatic fluctuations…