Quantum Creation of a Toy Universe without Inflation

TL;DR

This paper introduces a toy model where the universe's quantum creation naturally generates scale-invariant fluctuations without requiring inflation, using anisotropic scaling in a Horava-Lifshitz gravity framework.

Contribution

It presents a novel quantum cosmology model that produces scale-invariant fluctuations during universe creation without inflation or bounce mechanisms.

Findings

Fluctuations arise inside an instanton in Euclidean space.

The universe emerges with pre-existing scale-invariant fluctuations.

Anisotropic scaling in space and time is crucial for the mechanism.

Abstract

We propose a toy model for the origin of the universe, where the scale-invariant fluctuations are generated together with the quantum creation process of the universe. The fluctuations arise inside an instanton in the Euclidean domain of time. In the Lorentzian point of view, the universe emerges with passive, coherent and scale-invariant fluctuations present from the beginning, without the need of inflation or a bounce. For this mechanism to work, we need anisotropic scaling in space and time, which is realized in a toy model of Horava-Lifshitz gravity with a Lifshitz scalar field.