Massless (pseudo-)scalar seeds of CMB anisotropy
Astrophysics
2012-10-23 v1 General Relativity and Quantum Cosmology
High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
A primordial stochastic background of very weakly coupled massless (pseudo-)scalars can seed CMB anisotropy, when large-scale fluctuations of their stress-tensor re-enter the horizon during the matter-dominated era. A general relation between multipole coefficients of the CMB anisotropy and the seed's energy spectrum is derived. Magnitude and tilt of the observed anisotropies can be reproduced for the nearly scale-invariant axion spectra that are predicted in a particularly symmetric class of string cosmology backgrounds.
Keywords
Cite
@article{arxiv.astro-ph/9806015,
title = {Massless (pseudo-)scalar seeds of CMB anisotropy},
author = {R. Durrer and M. Gasperini and M. Sakellariadou and G. Veneziano},
journal= {arXiv preprint arXiv:astro-ph/9806015},
year = {2012}
}
Comments
9 pages, LATEX