Super-horizon perturbations and preheating
arXiv:astro-ph/0010639 · doi:10.1063/1.1363528
Abstract
We discuss the evolution of linear perturbations about a Friedmann-Robertson-Walker background metric, using only the local conservation of energy-momentum. We show that on sufficiently large scales the curvature perturbation on spatial hypersurfaces of uniform-density is constant when the non-adiabatic pressure perturbation is negligible. We clarify the conditions under which super-horizon curvature perturbations may vary, using preheating as an example.
4 pages, talk presented at "Cosmology and Particle Physics 2000", Verbier (Switzerland), 17-28 July 2000