A Primer on Dark Matter

TL;DR

This paper provides an accessible overview of dark matter, discussing its evidence, role in cosmology, experimental searches, and potential particle candidates, aimed at students new to the topic.

Contribution

It offers a concise, non-technical summary of dark matter's significance, evidence, and search strategies for an audience of students and newcomers.

Findings

Dark matter constitutes about five times more mass than ordinary matter.

Multiple experimental efforts are underway to detect dark matter particles.

Theoretical models predict various candidate particles for dark matter.

Abstract

Dark matter is a fundamental constituent of the universe, which is needed to explain a wide variety of astrophysical and cosmological observations. Although the existence of dark matter was first postulated nearly a century ago and its abundance is precisely measured, approximately five times larger than that of ordinary matter, its underlying identity remains a mystery. A leading hypothesis is that it is composed of new elementary particles, which are predicted to exist in many extensions of the Standard Model of particle physics. In this article we review the basic evidence for dark matter and the role it plays in cosmology and astrophysics, and discuss experimental searches and potential candidates. Rather than targeting researchers in the field, we aim to provide an accessible and concise summary of the most important ideas and results, which can serve as a first entry point for advanced undergraduate students of physics or astronomy.