Sourcing Dark Matter and Dark Energy from $α$-attractors

Abstract

Recently, Kallosh and Linde have drawn attention to a new family of superconformal inflationary potentials, subsequently called $α$-attractors. The $α$-attractor family can interpolate between a large class of inflationary models. It also has an important theoretical underpinning within the framework of supergravity. We demonstrate that the $α$-attractors have an even wider appeal since they may describe dark matter and perhaps even dark energy. The dark matter associated with the $α$-attractors, which we call $α$-dark matter ($α$DM), shares many of the attractive features of fuzzy dark matter, with $V(φ) = \frac{1}{2}m^2φ^2$, while having none of its drawbacks. Like fuzzy dark matter, $α$DM can have a large Jeans length which could resolve the cusp-core and substructure problems faced by standard cold dark matter. $α$DM also has an appealing tracker property which enables it to converge to the late-time dark matter asymptote, $\langle w\rangle \simeq 0$, from a wide range of initial conditions. It thus avoids the enormous fine-tuning problems faced by the $m^2φ^2$ potential in describing dark matter.

43 pages, 22 figures, Some clarifications and an additional reference. Main results unchanged. Accepted for publication in JCAP