Cosmic reionization and 21cm observations

B. Ciardi1
1Max Planck Institute for Astrophysics

The reionization of the intergalactic medium represents a major phase transition undergone by our Universe. In this talk I will discuss our theoretical understanding of the process, together with current observational constraints and the progress expected with measurements of the 21cm line from high redshift neutral hydrogen with instruments like LOFAR and SKA.