Tuning, Ergodicity, Equilibrium and Cosmology

Abstract

I explore the possibility that the cosmos is fundamentally an equilibrium system, and review the attractive features of such theories. Equilibrium cosmologies are commonly thought to fail due to the ``Boltzmann Brain'' problem. I show that it is possible to evade the Boltzmann Brain problem if there is a suitable coarse grained relationship between the fundamental degrees of freedom and the cosmological observables. I make my main points with simple toy models, and then review the de Sitter equilibrium model as an illustration.

11 pages including 2 figures and 4 tables

References in corpus (4)

• Eternal inflation and its implications
• The Measure Problem in Cosmology
• The Born Rule Dies
• No Firewalls or Information Problem for Black Holes Entangled with Large Systems

Cited by in corpus (5)

• Modifications to Cosmological Power Spectra from Scalar-Tensor Entanglement and their Observational Consequences
• Transients in finite inflation
• Einselection, Equilibrium and Cosmology
• The Log Log Prior for the Frequency of Extraterrestrial Intelligences
• Adapted Caldeira-Leggett Model