"Where is everybody?" the physicist Enrico Fermi once famously asked, disappointed that aliens hadn't contacted us yet. Over 50 years later, Fermi would feel even more snubbed. As Paul Davies puts it in the title of his latest book, the Search for Extraterrestrial Intelligence (SETI) has turned up nothing but an "eerie silence." Davies, a physicist, cosmologist, and astrobiologist, thinks that if we're going to have better luck, we'll need to get creative. In a Big Think interview that boldly goes into weird, wild territory, he describes how we can take SETI to the next level.

The first place we'll need to look, according to Davies? Earth. If life is a relatively common phenomenon, cosmically speaking, it's conceivable that it could have spontaneously originated more than once on our own planet. By scouring the biosphere for organisms that are not part of our "tree of life"—aliens among us, so to speak—we may find clues as to the nature and prevalence of life elsewhere in the universe. And if we're willing to get very creative, we might start sleuthing for traces of intelligent life that have nothing to do with radio signals—such as decayed fuel waste from long-ago spaceship voyages through our solar system, or, you guessed it, hidden messages in our DNA.

Davies cheerfully admits that the latter is a "crazy idea," which is fortunate, because when we do find aliens, we'll want the first guy to contact them to have a good head on his shoulders. That's right: as chair of the official SETI Post-Detection Task Group, Davies gets to be the first human being on the line if ET ever phones. So what would he say if we actually made contact? Something in the universal language, math, of course. So much for "Take me to your leader."

Later in the interview, Davies also explains how physics could help cure cancer and how cancer itself is a sort of alien life form—"Life 1.1," as he calls it. For a grand finale, he explains the universe in one minute.