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Can we prevent the end of the world?

1,318,858 views | Martin Rees • TED2014

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?

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?

This talk was presented at an official TED conference. TED's editors chose to feature it for you.

About the speaker

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Lord Martin Rees, one of the world's most eminent astronomers, is an emeritus professor of cosmology and astrophysics at the University of Cambridge and the UK's Astronomer Royal. He is one of our key thinkers on the future of humanity in the cosmos.

This talk was presented at an official TED conference. TED's editors chose to feature it for you.