Dark Matter

Abstract

The search for dark matter constitutes an ongoing effort that is at the core of modern astronomy. The dark matter problem was first posed more than fifty years ago, and it remains largely unresolved. We have learnt much about its distribution in the universe, yet remain abysmally ignorant as to its nature. These lectures will address two questions: where is the dark matter, and what is its nature? In the first lecture, I will, after reviewing the history of dark matter, describe the status of dark matter probes over scales that range from the solar neighborhood to galaxy halos, clusters, and superclusters up to the horizon scale. The second lecture will focus on the composition of the dark matter. I will describe the cases for both baryonic and non-baryonic matter, and review the various dark matter candidates.