Quintessence in a quandary: prior dependence in dark energy models
Abstract
The archetypal theory of dark energy is quintessence: a minimally coupled scalar field with a canonical kinetic energy and potential. By studying random potentials we show that quintessence imposes a restricted set of priors on the equation of state of dark energy. Focusing on the commonly-used parametrisation, , we show that there is a natural scale and direction in the plane that distinguishes quintessence as a general framework. We calculate the expected information gain for a given survey and show that, because of the non-trivial prior information, it is a function of more than just the figure of merit. This allows us to make a quantitative case for novel survey strategies. We show that the scale of the prior sets target observational requirements for gaining significant information. This corresponds to a figure of merit FOM, a requirement that future galaxy redshift surveys will meet.
Keywords
Cite
@article{arxiv.1406.2301,
title = {Quintessence in a quandary: prior dependence in dark energy models},
author = {David J. E. Marsh and Philip Bull and Pedro G. Ferreira and Andrew Pontzen},
journal= {arXiv preprint arXiv:1406.2301},
year = {2014}
}
Comments
5 pages, 3 figures. For the busy reader, Fig. 1 is the money plot. v2: Minor changes, matches published version. Code open source at gitorious.org/random-quintessence