Axions and Dark Matter

TL;DR

This paper reviews the key features of axions as a promising candidate for dark matter, which makes up about 23% of the universe's energy density, highlighting their theoretical motivation and properties.

Contribution

It provides a concise overview of axion properties and their role as dark matter candidates, emphasizing their significance in beyond standard model theories.

Findings

Axions are a viable dark matter candidate.

They solve the strong CP problem.

Axions have specific properties that make them attractive dark matter candidates.

Abstract

Dark matter constitutes about $23\%$ of the total energy density of the universe but its properties are still little known besides that it should be composed by cold and weakly interacting particles. Many beyond standard model theories can provide proper candidates to serve as dark matter and the axion introduced to solve the strong CP problem turns out to be an attractive one. In this paper, we briefly review several important features of the axion and the axion dark matter.