# Gravitational waves generated from the cosmological QCD phase transition within AdS/QCD

## TL;DR

This paper investigates gravitational waves from the cosmological QCD phase transition using AdS/QCD models, predicting detectable signals for upcoming gravitational wave observatories, and linking black hole evaporation to phase transition duration.

## Contribution

It introduces a novel approach to model gravitational waves from QCD phase transitions via AdS/QCD and estimates their detectability with future observatories.

## Key findings

- Predicted gravitational wave spectrum and strain amplitude within hard and soft wall models.
- Bound on string length derived from phase transition duration.
- Detection prospects for IPTA and SKA for these gravitational waves.

## Abstract

We study the gravitational waves produced by the collision of the bubbles as a probe for the cosmological first order QCD phase transition, considering heavy static quarks. Using AdS/QCD and the correspondence between a first order Hawking-Page phase transition and confinement-deconfinement phase transition, we find the spectrum and the strain amplitude of the gravitational wave within the hard and soft wall models. We postulate the duration of the phase transition corresponds to the evaporation time of the black hole in the five dimensional dual gravity space, and thereby obtain a bound on the string length in the space and correspondingly on the duration of the QCD phase transition. We also show that IPTA and SKA detectors will be able to detect these gravitational waves, which can be an evidence for the first order deconfinement transition.