Contracting cosmologies and the swampland

We consider the cosmology obtained using scalar fields with a negative potential energy, such as employed to obtain an Ekpyrotic phase of contraction. Applying the covariant entropy bound to the tower of states dictated by the distance conjecture, we find that the relative slope of the potential |V '|/|V| is bounded from below by a constant of the order one in Planck units. This is consistent with the requirement to obtain slow Ekpyrotic contraction. We also derive a refined condition on the potential which holds near local minima of a negative potential.

Automated summary

This study investigates the cosmology obtained using scalar fields with negative potential energy, and applies the covariant entropy bound and distance conjecture to derive constraints on the potential. The findings suggest that the relative slope of the potential is bounded from below by a constant in Planck units for slow Ekpyrotic contraction.