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We report on a current investigation of the anisotropy pattern induced by cosmic strings on the cosmic microwave background radiation (MBR). We have numerically evolved a network of cosmic strings from a redshift of $Z = 100$ to the present…

Astrophysics · Physics 2007-05-23 B. Allen , R. R. Caldwell , E. P. S. Shellard , A. Stebbins , S. Veeraraghavan

Recent measurements of the cosmic microwave background (CMB) anisotropies by BOOMERANG and MAXIMA collaborations have tightened the observational constraints on theories of structure formation. They disagree with the predictions of…

Astrophysics · Physics 2009-10-31 Levon Pogosian

We investigate the effect of wiggly cosmic strings on the cosmic microwave background radiation anisotropy and matter power spectrum by modifying the string network model used by Albrecht et al.. We employ the wiggly equation of state for…

Astrophysics · Physics 2016-08-25 Levon Pogosian , Tanmay Vachaspati

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…

Astrophysics · Physics 2009-09-25 Leandros Perivolaropoulos , Richhild Moessner , Robert Brandenberger

We compare the anisotropies in the cosmic microwave background radiation measured by the COBE experiment to the predictions of cosmic strings. We use an analytic model for the $\Delta T/T$ power spectrum that is based on our previous…

High Energy Physics - Phenomenology · Physics 2009-10-22 David P. Bennett , Albert Stebbins , Francois R. Bouchet

We introduce a new technique to detect the discrete temperature steps that cosmic strings might have left in the cosmic microwave background (CMB) anisotropy map. The technique provides a validity test on the pattern search of cosmic…

Astrophysics · Physics 2009-11-11 E. Jeong , G. F. Smoot

This is a somewhat extended version of the original July 93 report. It is proved that the cosmological density perturbation is associated with a peculiar velocity field. This allows a simple formulation of cosmological perturbation theory,…

Astrophysics · Physics 2010-11-01 Marco Bruni , David H. Lyth

We study how the presence of world-sheet currents affects the evolution of cosmic string networks, and their impact on predictions for the cosmic microwave background (CMB) anisotropies generated by these networks. We provide a general…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-21 I. Yu. Rybak , A. Avgoustidis , C. J. A. P. Martins

We simulate the anisotropy in the cosmic microwave background (CMB) induced by cosmic strings. By numerically evolving a network of cosmic strings we generate full-sky CMB temperature anisotropy maps. Based on $192$ maps, we compute the…

Astrophysics · Physics 2008-11-26 B. Allen , R. R. Caldwell , E. P. S. Shellard , A. Stebbins , S. Veeraraghavan

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…

Astrophysics · Physics 2016-08-30 B. Allen , R. R. Caldwell , S. Dodelson , L. Knox , E. P. S. Shellard , A. Stebbins

Using an analytical model for the string network we show that the kurtosis of cosmic microwave background (CMB) temperature gradient maps is a good statistic to distinguish between the cosmic string model and inflationary models of…

Astrophysics · Physics 2011-05-10 R. Moessner , L. Perivolaropoulos , R. Brandenberger

Line discontinuities in cosmic microwave background anisotropy maps are a distinctive prediction of models with cosmic strings. These signatures are visible in anisotropy maps with good angular resolution and should be identifiable using…

Astrophysics · Physics 2009-06-23 Stephen Amsel , Joshua Berger , Robert H. Brandenberger

We briefly review certain aspects of cosmic microwave background anisotropies as generated in passive and active models of structure formation. We then focus on cosmic strings based models and discuss their status in the light of current…

Astrophysics · Physics 2009-11-07 Alejandro Gangui , Levon Pogosian , Serge Winitzki

Cosmic string networks generate cosmological perturbations actively throughout the history of the universe. Thus, the string sourced anisotropy of the cosmic microwave background is not affected by Silk damping as much as the anisotropy…

Astrophysics · Physics 2010-04-15 Levon Pogosian , S. -H. Henry Tye , Ira Wasserman , Mark Wyman

A recently proposed mechanism for large-scale structure in string cosmology --based on massless axionic seeds-- is further analyzed and extended to the acoustic-peak region. Existence, structure, and normalization of the peaks turn out to…

Astrophysics · Physics 2009-10-31 A. Melchiorri , F. Vernizzi , R. Durrer , G. Veneziano

We present updated constraints on cosmic string and superstring parameters derived from Cosmic Microwave Background (CMB) anisotropies. The constraints are obtained via Markov Chain Monte Carlo (MCMC) analyses of the full \textit{Planck}…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-23 Juhan Raidal , Anastasios Avgoustidis , Edmund Copeland , Adam Moss

The predictions of the inflationary LCDM paradigm match today's high-precision measurements of the cosmic microwave background anisotropy extremely well. The same data put tight limits on other sources of anisotropy. Cosmic strings are a…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Cora Dvorkin , Mark Wyman , Wayne Hu

The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history,…

In the near future, observations of the cosmic microwave background (CMB) anisotropies will provide accurate determinations of many fundamental cosmological parameters. In this paper, we analyse degeneracies among cosmological parameters to…

Astrophysics · Physics 2009-10-30 G. Efstathiou , J. R. Bond

Accurate measurements of the cosmic microwave background (CMB) anisotropies with an angular resolution of a few arcminutes can be used to determine fundamental cosmological parameters such as the densities of baryons, cold and hot dark…

Astrophysics · Physics 2016-01-13 J. Richard Bond , George Efstathiou , Max Tegmark
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