A paradox in the global description of the multiverse

TL;DR

The paper discusses a paradox in the global multiverse model where most observers are quantum fluctuation-based, conflicting with observations, and explores implications for the stability of vacua.

Contribution

It identifies a paradox in the global multiverse framework and derives constraints on metastable vacuum lifetimes based on observer distribution.

Findings

Most observers in the global multiverse arise from quantum fluctuations

The paradox challenges the global multiverse description unless we are atypical

Constraints on the maximum lifetime of metastable vacua are derived

Abstract

We use an argument by Page to exhibit a paradox in the global description of the multiverse: the overwhelming majority of observers arise from quantum fluctuations and not by conventional evolution. Unless we are extremely atypical, this contradicts observation. The paradox does not arise in the local description of the multiverse, but similar arguments yield interesting constraints on the maximum lifetime of metastable vacua.