Related papers: Observational Constraints on Cosmic String Product…
We perform a multiparameter likelihood analysis to compare measurements of the cosmic microwave background (CMB) power spectra with predictions from models involving cosmic strings. Adding strings to the standard case of a primordial…
The leading candidate for the very early universe is described by a period of rapid expansion known as inflation. While the standard paradigm invokes a single slow-rolling field, many different models may be constructed which fit the…
When cosmic strings are formed during inflation, they regrow to reach a scaling regime, leaving distinct imprints on the stochastic gravitational wave background (SGWB). Such signatures, associated with specific primordial features, can be…
We confront the predicted effects of hybrid inflationary models on the Cosmic Microwave Background (CMB) with three years of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Using model selection, we compare the ability of a simple…
We present a study of open inflation cosmological scenarios in which cosmic strings form betwen the two inflationary epochs. It is shown that in these models strings are stretched outside the horizon due to the inflationary expansion but…
Inflationary cosmology is the leading explanation of the very early universe. Many different models of inflation have been constructed which fit current observational data. In this work theoretical and numerical methods for constraining the…
A class of well-motivated models of inflation end by producing cosmic strings. The current status of efforts to calculate and observe the signals from such models are outlined, with a particular emphasis on cosmic strings, and on the Cosmic…
WMAP three-year data favors a red power spectrum at the level of 2 standard deviations, which provides a stringent constraint on the inflation models. In this note we use this data to constrain brane inflation models and find that KKLMMT…
We study effects of the cosmic string in the D-term inflation model on the cosmic microwave background (CMB) anisotropy. In the D-term inflation model, gauged cosmic string is usually formed, which may significantly affect the CMB…
At its very beginning, the universe is believed to have grown exponentially in size via the mechanism of inflation. The almost scale-invariant density perturbation spectrum predicted by inflation is strongly supported by cosmological…
ABSRACT: We review recent progress on testing the hypothesis of the existence of cosmic string perturbations in microwave background maps. Using an analytical model for the string network we show that the predicted amplitude and spectrum of…
We revisit D-term inflation with the bounds of the cosmic string tension from gravitational wave observations and consider the possible deviation of the spectral index compared with the $\Lambda$CDM model in light of prerecombination…
I elaborate on a link between the string--scale breaking of supersymmetry that occurs in a class of superstring models and the onset of inflation. The link rests on spatially flat cosmologies supported by a scalar field driven by an…
The inflationary paradigm provides a robust description of the peculiar initial conditions which are required for the success of the Hot Big Bang model of cosmology, as well as of the recent precision measurements of temperature…
We describe string production after angled brane inflation. First, we point out that there was a discrepancy in previous discussions. The expected tension of the cosmic string calculated from the four-dimensional effective Lagrangian did…
In this paper we show how the string landscape can be constrained using observational data. We illustrate this idea by focusing on Fibre Inflation which is a promising class of string inflationary models in type IIB flux compactifications.…
Detecting the parity-odd, or B-mode, polarization pattern in the cosmic microwave background radiation due to primordial gravity waves is considered to be the final observational key to confirming the inflationary paradigm. The search for…
In this thesis, consisting of two main parts, we study observational signatures of cosmic (super)strings in the context of D-brane inflation and properties of scalar perturbations on generic homogeneous inflating backgrounds. In the first…
We present a general set-up for inflation in string theory where the inflaton field corresponds to Wilson lines in compact space in the presence of magnetic fluxes. T-dualities and limits on the value of the magnetic fluxes relate this…
In the context of SUSY GUTs, GUT scale cosmic strings formed at the end of hybrid inflation are compatible with currently available CMB measurements. The maximum allowed cosmic strings contribution to the CMB data constrains the free…