Haloes of k-Essence
Abstract
We study gravitationally bound static and spherically symmetric configurations of k-essence fields. In particular, we investigate whether these configurations can reproduce the properties of dark matter haloes. The classes of Lagrangians we consider lead to non-isotropic fluids with barotropic and polytropic equations of state. The latter include microscopic realizations of the often-considered Chaplygin gases, which we find can cluster into dark matter halo-like objects with flat rotation curves, while exhibiting a dark energy-like negative pressure on cosmological scales. We complement our studies with a series of formal general results about the stability and initial value formulation of non-canonical scalar field theories, and we also discuss a new class of de Sitter solutions with spacelike field gradients.
Cite
@article{arxiv.astro-ph/0505207,
title = {Haloes of k-Essence},
author = {C. Armendariz-Picon and Eugene A. Lim},
journal= {arXiv preprint arXiv:astro-ph/0505207},
year = {2009}
}
Comments
34pages, single column double spacing, 7 figures, 3 Tables, RevTex4. Additional references and minor clarifications. To be submitted to JCAP