We live in times of extraordinary discovery. Exoplanets appear to be quite common in our galaxy. NASA’s Kepler Telescope has identified over 2,000 planetary candidates orbiting other stars. And yet the universe appears to be silent – at least when it comes to any detectable signs of alien civilizations, either at present in our galaxy or their remnants from the last couple of billion years.
And let’s be clear: it isn’t just the failure of SETI (the Search for ExtraTerrestrial Intelligence) to detect radio signals that constitutes “silence.” Indeed, there are strong reasons to believe that they have been looking in the worst possible way. No, the greatest SETI Observatory has been our own planet Earth, which had an oxygen atmosphere for up to two billion years but with no inhabitants higher than a slime mold to defend it against external colonization. Had alien visitors ever flushed a toilet or dropped a sandwich wrapper into Earth’s seas, the bio changes would have been huge and visible in our rocks.
Physicist Enrico Fermi famously asked, “Where is everybody?” The Fermi Paradox or The Great Silence refers to this quandary of why we have never encountered extraterrestrial civilizations. I’ve written about all this extensively in scientific papers and in fiction, and my latest novel,Existence reveals dozens of scenarios about first contact.
Many experts have weighed in with explanations for the Fermi Paradox, and I’ve observed a strange phenomenon among smart fellows like Stephen Hawking, Michio Kaku, Paul Davies and such. They all-too often seem to leap upon just one hypothesis – a bizarrely premature thing to do, especially in the only scientific field without any subject matter. I have chosen instead to spend the last 30 years cataloging and categorizing up to a hundred theories for the Great Silence. But I won’t list them here.