De Sitter Holography: Fluctuations, Anomalous Symmetry, and Wormholes

Understand

The Goheer-Kleban-Susskind no-go theorem says that the symmetry of de Sitter space is incompatible with finite entropy.

• The meaning and consequences of the theorem are discussed in the light of recent developments in holography and gravitational path integrals.
• The relation between the GKS theorem, Boltzmann fluctuations, wormholes, and exponentially suppressed non-perturbative phenomena suggests: the classical symmetry between different static patches is broken; and that eternal de Sitter space -- if it exists at all -- is an ensemble average.