We present a brief overview of attempts to construct de Sitter vacua in string theory and
explain how the results of this 20-year endeavor could point to the fact that string theory …

This white paper summarizes recent progress in the cosmological bootstrap, an approach to
the study of the statistics of primordial fluctuations from consistency with unitarity, locality and …

We give a brief overview of the string landscape and techniques used to construct string
compactifications. We then explain how this motivates the notion of the swampland and …

We review the advanced version of the KKLT construction and pure de Sitter supergravity,
involving a nilpotent multiplet, with regard to various conjectures that de Sitter state cannot …

Observers in de Sitter space can only access the space up to their cosmological horizon.
Assuming thermal equilibrium, we use the quantum Ryu–Takayanagi or island formula to …

These lectures present an elementary discussion of some background material relevant to
the problem of de Sitter quantum gravity. The first two lectures discuss the classical …

Massive spin s⩾ 3/2 fields can become partially massless in cosmological backgrounds. In
the plane spanned by m2 and Λ, there are lines where new gauge invariances permit …

T-Duality on a timelike circle does not interchange IIA and IIB string theories, but takes the
IIA theory to a type IIB∗ theory and the IIB theory to a type IIA∗ theory. The type II∗ theories …

Abstract The (m 2, Λ) plane of spin s> 1 massive fields in (anti-) de Sitter space backgrounds
is shown to consist of separate phases, divided by lines of novel “partially massless” gauge …

We give a detailed construction of gauged N= 8 supergravity theories in five dimensions with
Yang-Mills gauge groups SO (p, 6− p)(p= 0, 1, 2, 3), physical global symmetry SU (1, 1), and …