Ultralight axion and modern cosmology tensions

TL;DR

This paper explores how a string-inspired ultralight axion model can address key issues in modern cosmology, including the Hubble tension, gravitational wave background, and early supermassive black hole formation.

Contribution

It introduces a string-inspired axion model that offers a unified solution to multiple outstanding cosmological problems.

Findings

Potential resolution of Hubble tension

Explanation for stochastic gravitational wave background

Account for early supermassive black hole formation

Abstract

String-inspired axion model is considered to comprehensively solve the problems of modern cosmology, Hubble tension problem, the origin of the stochastic gravitational wave background, and too early formation of supermassive black holes at high $z$.