Baryonic Dark Matter: Theory and Experiment. Overview

The general arguments for baryonic and galactic dark matter are presented. Limits coming from a variety of theoretical considerations and observations are discussed. The surviving candidates for galactic baryonic dark matter seem most likely to be in the form of compact objects and could be in one of two mass windows: either in the brown dwarf regime or in the mass range corresponding to supermassive black holes. Microlensing towards LMC is probing the first window. It is important to keep in mind that these experiments may detect compact heavy objects, independent of their constituency.