Jacob Tsimerman, a recent recipient of the Fields Medal, believes that higher mathematics can help curb the dangers of runaway artificial intelligence.

A Cambridge professor has transcribed a handwritten story that the famous mathematician wrote in the year before his death, presenting a different side of him.

A San Francisco company paid nearly $1 million for the solution to an unsolved code in Kryptos, a sculpture on the C.I.A. grounds. Soon it will become an online challenge.