Building Supergravity Quintessence Model

Understand

It was recently pointed out that the cosmological constant (even metastable one) belongs to the so-called "swampland" and hence cannot be obtained as the low-energy limit of string theory that requires $|\nabla V| > c V$.

• If true, the dark energy needs to be described by an evolving scalar field, i.e., quintessence with $w>-1$ within supergravity.
• However, the large hierarchy between the supersymmetry breaking scale and the energy scale of dark energy imposes a challenge on building quintessence models in supergravity as the quintessence field typically acquires a mass of order the gravitino mass.
• We investigate two approaches to circumvent this obstacle.