De Sitter Quantum Breaking, Swampland Conjectures and Thermal Strings

Abstract

We argue that under certain assumptions the quantum break time approach and the trans-Planckian censorship conjecture both lead to de Sitter swampland constraints of the same functional form. It is a well known fact that the quantum energy-momentum tensor in the Bunch-Davies vacuum computed in the static patch of dS breaks some of the isometries. Proposing that this is a manifestation of quantum breaking of dS, we analyze some of its consequences. In particular, this leads to a thermal matter component that can be generalized to string theory in an obvious way. Imposing a censorship of quantum breaking, we recover the no eternal inflation bound in the low temperature regime, while the stronger bound from the dS swampland conjecture follows under a few reasonable assumptions about the still mysterious, presumably topological, high-temperature regime of string theory.