de Sitter equilibrium as a fundamental framework for cosmology

TL;DR

This paper explores the idea that cosmology can be understood as fluctuations around a de Sitter equilibrium state, addressing common questions and issues like the Boltzmann Brain problem, and connecting to recent theoretical developments.

Contribution

It presents a comprehensive review of the de Sitter equilibrium framework as a fundamental approach to cosmology, clarifying its advantages and resolving key conceptual issues.

Findings

The framework avoids the Boltzmann Brain problem.

It relates de Sitter equilibrium to the clock ambiguity in quantum cosmology.

Provides a coherent interpretation of cosmological fluctuations.

Abstract

Cosmology might turn out to be the study of fluctuations around a "de Sitter equilibrium" state. In this article I review the basic ideas and the attractive features of this framework, and respond to a number common questions raised about the de Sitter equilibrium picture. I show that this framework does not suffer from the "Boltzmann Brain" problem, and relate this cosmological picture to recent work on the "clock ambiguity".