Ray P. Norris
It seems inconceivable that we are alone, given the billions of stars like our Sun that are in our Galaxy, and the growing number which seem to have planets around them. Surely there just be some other Earths out there, and surely there must be other civilisations like ours? So how come we’ve never met them, or heard from them, despite the fact that Earth-bound scientists have been searching for years for a faint whisper from one of these alien civilisations?
In this talk, I’ll start by trying to guess how many Earth-like civilisations might be out there, describe our attempts to eavesdrop on their signals, or make contact, and think of possible reasons why they never seem to call us. I’ll end up by examining a question which is still a bit of a worry: what would we do if they did call?