Attractors, Universality and Inflation

TL;DR

This paper explores the initial conditions for inflation, highlighting how including scalar potential data reveals the significance of inflection point inflation and universality classes, thereby affecting the likelihood and predictability of inflation.

Contribution

It extends the analysis of inflation initial conditions by incorporating scalar potential data, demonstrating the role of inflection points and attractor dynamics in inflation likelihood.

Findings

Inflection point inflation enhances inflation likelihood to an inverse cubic power law.

Universality classes emerge from inflection point inflation dynamics.

Including potential data alters the phase space analysis of initial conditions.

Abstract

Studies of the initial conditions for inflation have conflicting predictions from exponential suppression to inevitability. At the level of phase space, this conflict arises from the competing intuitions of CPT invariance and thermodynamics. After reviewing this conflict, we enlarge the ensemble beyond phase space to include scalar potential data. We show how this leads to an important contribution from inflection point inflation, enhancing the likelihood of inflation to an inverse cubic power law. In the process, we emphasize the attractor dynamics of the gravity-scalar system and the existence of universality classes from inflection point inflation. Finally, we comment on the predictivity of inflation in light of these results.