Université de GenèveDépartement de Physique ThéoriqueCAP Genève

Cosmic Microwave Background temperature and polarization anisotropies from the large-N limit of global defects

Date: 
15. November 2013
Cite as: 
E. Fenu, D. G. Figueroa, R. Durrer, J. Garcia-Bellido and M. Kunz, [arXiv:1311.3225].
Summary: 

 Cosmic Microwave Background temperature and polarization anisotropies from the large-N limit of global defects 

We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N)-theories. We point out a problem in the standard approach of treating the radiation-matter transition by interpolating the eigenvectors of the unequal-time correlators of the source energy-momentum tensor. This affects the CMB predictions from all type of cosmic defects. We propose a method to overcome this difficulty, and find that in the large-N global model that we study, differences in the final CMB power spectra amplitudes reach up to 25%, when compared to implementations of the eigenvector interpolation technique. We discuss as well how to optimally search for the contribution in the CMB from active sources such as cosmic defects, in experiments like Planck, COrE and PRISM.

Address

Département de Physique Théorique
Université de Genève
24, quai Ernest Ansermet
1211 Genève 4
Switzerland
Directions & contact