The Self-Organized de Sitter Universe

TL;DR

This paper introduces a background-independent quantum gravity model using a nonperturbative path integral approach, demonstrating the spontaneous emergence of a de Sitter universe through self-organization, with quantum fluctuations analyzed near the Planck scale.

Contribution

It presents a novel nonperturbative, diffeomorphism-invariant quantum gravity theory that shows a de Sitter universe naturally emerges from the dynamics.

Findings

A de Sitter universe emerges on large scales in simulations.

Quantum fluctuations remain small until near the Planck scale.

The model exhibits self-organizing, entropic behavior similar to condensed matter systems.

Abstract

We propose a theory of quantum gravity which formulates the quantum theory as a nonperturbative path integral, where each spacetime history appears with a weight given by the exponentiated Einstein-Hilbert action of the corresponding causal geometry. The path integral is diffeomorphism-invariant (only geometries appear) and background-independent. The theory can be investigated by computer simulations, which show that a de Sitter universe emerges on large scales. This emergence is of an entropic, self-organizing nature, with the weight of the Einstein-Hilbert action playing a minor role. Also the quantum fluctuations around this de Sitter universe can be studied quantitatively and remain small until one gets close to the Planck scale. The structures found to describe Planck-scale gravity are reminiscent of certain aspects of condensed-matter systems.