A world of self-improving machines has lived in fiction for more than a century. What gives that old fear new force now is ...

Cosmologists have spent decades trying to pin down exactly how fast the universe is flying apart and whether that rate is ...

The original version of this story appeared in Quanta Magazine. In 1950 the Italian physicist Enrico Fermi was discussing the possibility of intelligent alien life with his colleagues. If alien ...

In most narratives, the story of evolution is the story of organisms emerging from the ocean and eventually populating the land. But for some species that evolution also involved a return trip. Dozens ...