"People believe all sorts of things about how the world's going to end," said Matthew Billet, social psychologist at University of California, Irvine, US, in conversation with Science unscripted hosts, Conor Dillon and Gabriel Borrud. "Some people mean human extinction," Billet said. "Some people mean the collapse of civilization or some sort of transformation of civilization as we know it, sometimes leading to a utopia, or a revitalization of humanity. And some people mean the complete destruction of Earth [by] a comet or a solar flare or something." Most of us have had such thoughts about the end of the world. But what Billet and his colleagues wanted to find out was how these beliefs affect people's attitudes.…