Inflation with two-form field: the production of primordial black holes and gravitational waves

TL;DR

This paper explores how a two-form field during inflation can produce primordial black holes and gravitational waves, offering testable predictions for future space-based detectors.

Contribution

It introduces a novel inflationary scenario involving a two-form field that generates primordial black holes and gravitational waves, connecting string theory components with observable cosmological signals.

Findings

Primordial black holes can form from two-form field particle production during inflation.

Secondary gravitational waves sourced by curvature perturbations are detectable by future interferometers.

The model predicts specific power spectra for gravitational waves that are within observational reach.

Abstract

Antisymmetric tensor field (two-form field) is a ubiquitous component in string theory and generally couples to the scalar sector through its kinetic term. In this paper, we propose a cosmological scenario that the particle production of two-form field, which is triggered by the background motion of the coupled inflaton field, occurs at the intermediate stage of inflation and generates the sizable amount of primordial black holes as dark matter after inflation. We also compute the secondary gravitational waves sourced by the curvature perturbation and show that the resultant power spectra are testable with the future space-based laser interferometers.