Life in the Universe

The discovery that nearly every star in our galaxy has an (ex)planet or planetary system seems to indicate that life in the Universe might be a common phenomena. However, cosmic explosions produce copious amount of high-energy radiation that could be potentially dangerous to life survival. In this talk I will present recent advances in our understanding of how life extinctions takes place, how one can explain Fermi’s paradox and will also show what kind of universes are most favorable to harbour life, specially in connection with the appearance of the cosmological constant.