%0 Journal Article
%T A natural cosmological constant from chameleons
%A Horatiu Nastase
%A Amanda Weltman
%J Physics
%D 2013
%I arXiv
%X We present a simple model where the effective cosmological constant appears from chameleon scalar fields. For a Kachru-Kallosh-Linde-Trivedi (KKLT)-inspired form of the potential and a particular chameleon coupling to the local density, patches of approximately constant scalar field potential cluster around regions of matter with density above a certain value, generating the effect of a cosmological constant on large scales. This construction addresses both the cosmological constant problem (why $\Lambda$ is so small, yet nonzero) and the coincidence problem (why $\Lambda$ is comparable to the matter density now).
%U http://arxiv.org/abs/1302.1748v3