Thermodynamic Aspects of the de Sitter Conjecture

The Swampland program founded in 2005 by C.Vafa has seen a huge rise of interest in recent years. The aim of this program is to restrain the number of consistent looking low-energy effective theories to those, which can actually be consistently coupled to a theory of quantum gravity. A lot of work regarding the swampland program has been put into the formulation of a multitude of remarkable conjectures, which also seem to be interconnected. This thesis will explore the connections between different conjectures regarding the exclusion of (meta-)stable de Sitter solutions derived from a theory of quantum gravity. 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. For that purpose we employ the proposal that quantum breaking of dS is induced by neglecting modes beyond the dS horizon. This leads to a thermal matter component that can be generalized to string theory in a direct fashion. 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 high-temperature regime of string theory