Related papers: Cosmic Defects and CMB anisotropy
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 ($h$),…
The dimming of Type Ia supernovae could be the result of Hubble-scale inhomogeneity in the matter and spatial curvature, rather than signaling the presence of a dark energy component. A key challenge for such models is to fit the detailed…
Under the assumption that the concordance Lambda cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with…
The number of cosmic strings in the observable universe is relevant in determining the probability of detecting such cosmic defects through their gravitational signatures. In particular, we refer to the observation of gravitational lensing…
I review the general aspects of cosmological parameter estimation from observations of the cosmic microwave background (CMB) temperature anisotropies in the framework of inflationary adiabatic models. The most recent CMB datasets are…
We present a formalism for analyzing interferometric observations of Cosmic Microwave Background (CMB) anisotropy and polarization data. The formalism is based upon the ell-space expansion of the angular power spectrum favoured in recent…
If current ideas about unified field theories are correct, macroscopic cosmic defects may well exist. The observation of such an entity would have enormous significance for our understanding of fundamental physics. This paper points out a…
Making use of the wealth of new observational data coming from the sky it is possible to constrain particle physics theories beyond the Standard Model. One way to do this is illustrated in this article: a subset of theories admits cosmic…
Non-canonical scaling of the form $\rho_{x} \propto \rho_{m} a^{\xi}$, where $\rho_{x}$ and $\rho_{m}$ are the energy densities of dark energy and dark matter, respectively, provides a natural way to address the coincidence problem -why the…
We demonstrate that recent measurements of Cosmic Microwave Background temperature and polarization anisotropy made by the ACBAR, QUAD and BICEP experiments substantially improve the cosmological constraints on possible variations of the…
We propose a new method for a numerical computation of the angular bispectrum of the CMB anisotropies arising from active models such as cosmic topological defects, using a modified Boltzmann code based on CMBFAST. The method does not use…
Observations of the cosmic microwave background (CMB) together with weak lensing measurements of the clustering of large scale cosmological structures and local measurements of the Hubble constant pose a challenge to the standard…
We calculate predictions from defect models of structure formation for both the matter and Cosmic Microwave Background (CMB) over all observable scales. Our results point to a serious problem reconciling the observed large-scale galaxy…
We calculate the angular scale of the acoustic oscillation from the BOOMERANG and WMAP data on the cosmic microwave background (CMB) to constrain the holographic dark energy model recently proposed by Li. We find that only the phantom-like…
The Planck experiment will soon provide a very accurate measurement of Cosmic Microwave Background anisotropies. This will let cosmologists determine most of the cosmological parameters with unprecedented accuracy. Future experiments will…
The cosmic microwave background (CMB) comprises the oldest photons in the universe and is arguably our most direct cosmological observable. All precise and accurate measurements of its attributes serve to distinguish between cosmological…
Several anomalies appear to be present in the large-angle cosmic microwave background (CMB) anisotropy maps of WMAP. One of these is a lack of large-scale power. Because the data otherwise match standard models extremely well, it is natural…
The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological…
We explore the use of random forest and gradient boosting, two powerful tree-based machine learning algorithms, for the detection of cosmic strings in maps of the cosmic microwave background (CMB), through their unique Gott-Kaiser-Stebbins…
We compute cosmic microwave background angular power spectra for scaling seed models of structure formation. A generic parameterization of the energy momentum tensor of the seeds is employed. We concentrate on two regions of parameter space…