Martin Rees: Can we prevent the end of the world?

A post-apocalyptic Earth, emptied of humans, seems like the stuff of science fiction TV and movies. But in this short, surprising talk, Lord Martin Rees asks us to think about our real existential risks — natural and human-made threats that could wipe out humanity. As a concerned member of the human race, he asks: What’s the worst thing that could possibly happen? TEDTalks is a daily video podcast of the best talks and performances from the TED Conference, where the world’s leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design — plus science, business, global issues, the arts and much more. Find closed captions and translated subtitles in many languages at Follow TED news on Twitter: Like TED on Facebook: Subscribe to our channel: