The formation of low-mass stars and brown dwarfs
  It is estimated that ~60% of all stars (including brown dwarfs) have masses
below 0.2Msun. Currently, there is no consensus on how these objects form. I
will briefly review the four main theories for the formation of low-mass
objects: turbulent fragmentation, ejection of protostellar embryos, disc
fragmentation, and photo-erosion of prestellar cores. I will focus on the disc
fragmentation theory and discuss how it addresses critical observational
constraints, i.e. the low-mass initial mass function, the brown dwarf desert,
and the binary statistics of low-mass stars and brown dwarfs. I will examine
whether observations may be used to distinguish between different formation
mechanisms, and give a few examples of systems that strongly favour a specific
formation scenario. Finally, I will argue that it is likely that all mechanisms
may play a role in low-mass star and brown dwarf formation.
