For more than a century we have been broadcasting our presence to the cosmos. This year, the faintest signals from the world’s first major televised event – the Nazi-hosted 1936 Olympics – will have passed several potentially habitable planets. The first season of Game of Thrones has already reached the nearest star beyond our Solar System.

So why hasn’t ET called us back?

There are plenty of obvious answers. Maybe there are no intelligent space aliens in our immediate cosmic vicinity. Perhaps they have never evolved beyond unthinking microbial slime or – based on our transmissions – aliens have concluded it is safer to stay away. There is, however, another explanation: ET is nothing like us.