Dissipative Emergence of Inflation from Quasi-Cyclic Universe

TL;DR

This paper explores how a dissipative mechanism in a closed universe with a plateau potential can naturally lead to inflation, bounce, or cyclic phases, providing insights into the universe's initial conditions and evolution.

Contribution

It introduces a dissipative dynamics framework that explains the emergence of inflation and cyclic behavior in a closed universe with plateau potentials, linking initial conditions to observable outcomes.

Findings

Dissipative effects enable smooth transition into inflation.

Multiple bounce and cyclic scenarios are possible.

Implications for the universe's wave function and initial conditions.

Abstract

Inflationary models, especially those with plateau-type potentials, are consistent with the cosmological data, but inflation itself does not resolve the initial singularity. This singularity is resolved, for example, by the idea of the quantum creation of the Universe from nothing such as the tunneling and no-boundary proposals. The simplest one predicts a closed Universe. Motivated by these facts, we investigate the classical dynamics of a closed universe with a plateau-type potential. Depending on the initial inflaton field value, the universe can undergo a variety of events: an immediate big crunch, a bounce or cyclic phase, and inflation. Although the non-inflationary solutions may appear irrelevant to our Universe, they can be turned into single or multiple bounces followed by inflation, taking into account the interactions necessary for the reheating of the Universe after inflation. Thus, the dissipative mechanism in our setup explains both the graceful entry to and exit from inflation and gives us an indirect observational handle on the Universe just after creation. We also comment on the implications of these solutions for probabilistic interpretations of the wave function of the Universe.