Cosmological Implications of the Supergravity Tracking Potential

Abstract

It is demonstrated that any realistic model of quintessence should be based on Supergravity since, when the scalar field is on tracks today, $Q\approx m_{\mathrm{Pl}}$. This improves the agreement between theoretical predictions and the current observations. In particular, a generic property is that ratio ${\omega }_{\mathrm{Q}}\equiv p_{\mathrm{Q}}/{\rho }_{\mathrm{Q}}$ is pushed towards -1. A string-inspired model is proposed where the potential is given by $V(Q)=\frac{{\Lambda }^{4+\alpha }}{Q^{\alpha }}{e}^{\frac{\kappa }{2}{Q}^2}$. The model predicts ${\omega }_{\mathrm{Q}}\approx -0.82$, a value less that one sigma from the current likehood value.

Comments: 4 pages, 2 figures, presented at the Journees Relativistes 99, Weimar, September 12-17, 1999