Galactic exploration by directed self-replicating probes, and its implications for the Fermi paradox

This paper proposes a long-term scheme for robotic exploration of the galaxy, and then considers the implications in terms of the ‘Fermi paradox’ and our search for extraterrestrial intelligence (ETI). We discuss the ‘Galactic ecology’ of civilizations in terms of the parametersT(time between ET civilizations arising) andL, the lifetime of these civilizations. Six different regions are described.