English

Islands in Multiverse Models

High Energy Physics - Theory 2022-04-14 v3 General Relativity and Quantum Cosmology

Abstract

We consider multiverse models in two-dimensional linear dilaton-gravity theories as toy models of false vacuum eternal inflation. Coupling conformal matter we calculate the Von Neumann entropy of subregions. When these are sufficiently large we find that an island develops covering most of the rest of the multiverse, leading to a Page-like transition. This resonates with a description of multiverse models in semiclassical quantum cosmology, where a measure for local predictions is given by saddle point geometries which coarse-grain over any structure associated with eternal inflation beyond one's patch.

Keywords

Cite

@article{arxiv.2108.01278,
  title  = {Islands in Multiverse Models},
  author = {Sergio E. Aguilar-Gutierrez and Aidan Chatwin-Davies and Thomas Hertog and Natalia Pinzani-Fokeeva and Brandon Robinson},
  journal= {arXiv preprint arXiv:2108.01278},
  year   = {2022}
}

Comments

54 pages, 20 figures; v2 reflects accepted version; v3 added erratum and companion addendum

R2 v1 2026-06-24T04:46:43.577Z