Viscous modes, isocurvature perturbations and CMB initial conditions
Cosmology and Nongalactic Astrophysics
2015-06-23 v2 General Relativity and Quantum Cosmology
High Energy Physics - Theory
Abstract
When the predecoupling plasma is thermodynamically reversible its fluctuations are classified in terms of the adiabatic and entropic modes. A different category of physical solutions, so far unexplored, arises when the inhomogeneities of the viscosity coefficients induce computable curvature perturbations. The viscous modes are explicitly illustrated and compared with the conventional isocurvature solutions.
Keywords
Cite
@article{arxiv.1502.01614,
title = {Viscous modes, isocurvature perturbations and CMB initial conditions},
author = {Massimo Giovannini},
journal= {arXiv preprint arXiv:1502.01614},
year = {2015}
}
Comments
9 pages, no figures; corrected typos; to appear in Physical Review as a Rapid Communication