Composite Hybrid Inflation: Dilaton and Waterfall Pions

TL;DR

This paper explores a novel hybrid inflation model based on a composite field theory involving a dilaton and pions, constrained by walking dynamics, predicting specific scales and potential phenomenological implications.

Contribution

It introduces a composite hybrid inflation model with a dilaton and pions, constrained by walking dynamics, and predicts specific energy scales and phenomenological consequences.

Findings

Successful hybrid inflation with dilaton as inflaton and pions as waterfall fields.

Predicted dilaton scale around Planck scale, inflation scale ~10^{10} GeV.

Pion scale around 10^{14} GeV.

Abstract

We investigate the possibility that inflation originates from a composite field theory, in terms of an effective chiral Lagrangian involving a dilaton and pions. The walking dynamics of the theory constrain the potential in a specific way, where the anomalous dimensions of operators involving pions play a crucial role. For realistic values of the anomalous dimensions, we find a successful hybrid inflation occurring via the dilaton-inflaton, with the pions acting as waterfall fields. Compositeness consistency strongly constrain the model, predicting a dilaton scale $f_\chi \sim \mathcal{O} (1)$ in unit of the Planck scale, an inflation scale $H_\text{inf} \sim 10^{10}$ GeV, and the pion scale around $10^{14}$ GeV. We further discuss possible phenomenological consequences of this theory.