Cosmologist Sean Carroll attacks -- in an entertaining and thought-provoking tour through the nature of time and the universe -- a deceptively simple question: Why does time exist at all? The potential answers point to a surprising view of the nature of the universe, and our place in it.

By analyzing raw data on violent incidents in the Iraq war and others, Sean Gourley and his team claim to have found a surprisingly strong mathematical relationship linking the fatality and frequency of attacks.

What do 24,000 ideas look like? Ecologist Eric Berlow and physicist Sean Gourley apply algorithms to the entire archive of TEDx Talks, taking us on a stimulating visual tour to show how ideas connect globally.