Exponential potentials and cosmological scaling solutions
摘要
We present a phase-plane analysis of cosmologies containing a barotropic fluid with equation of state , plus a scalar field with an exponential potential where . In addition to the well-known inflationary solutions for , there exist scaling solutions when in which the scalar field energy density tracks that of the barotropic fluid (which for example might be radiation or dust). We show that the scaling solutions are the unique late-time attractors whenever they exist. The fluid-dominated solutions, where at late times, are always unstable (except for the cosmological constant case ). The relative energy density of the fluid and scalar field depends on the steepness of the exponential potential, which is constrained by nucleosynthesis to . We show that standard inflation models are unable to solve this `relic density' problem.
引用
@article{arxiv.gr-qc/9711068,
title = {Exponential potentials and cosmological scaling solutions},
author = {Edmund J Copeland and Andrew R Liddle and David Wands},
journal= {arXiv preprint arXiv:gr-qc/9711068},
year = {2011}
}
备注
6 pages RevTeX file with four figures incorporated (uses RevTeX and epsf). Matches published version