We explore in this work whether the slotheon model of dark energy obeys the swampland criteria of string theory. Since a de Sitter vacuum is very difficult to construct in string theory the cosmological constant as an explanation of dark energy is almost ruled out in string theory as it involves a scalar potential $V$ with positive local minimum that ends up to a stable (or metastable) de Sitter (ds) vacuum. In the quintessence model, however, if the derivative of the scalar potential $V$ ($\nabla V$) is small and $\frac{|\nabla V|}{V}\sim \mathcal{O}(1)$ then in this situation the potential $V$ can be positive but the scalar field may not be at the minimum. For a consistent quantum theory of gravity the theory should not have any ds or metastable ds vacua. In this regard the swampland criterion is proposed which any low energy theory should obey to be consistent with the quantum theory of gravity. This criterion is written as $|\nabla V|/V>c\sim \mathcal{O}(1)$. In this work we consider a scalar field model for dark energy namely the slotheon dark energy model inspired by the theories of extra dimensions and show that this dark energy model agrees better with the swampland criteria than the quintessence dark energy model.

• Received 9 April 2019

DOI:https://doi.org/10.1103/PhysRevD.100.024006