Scroll down to listen to Amir Aczel speaking before an audience at Google, Cambridge, Massachusetts, about the Khmer Zero and his search for the stele containing the oldest representation of zero ever found. This talk is based on his book, Finding Zero, and provides a good introduction to the story of his search for the artifact thought to have been lost during the Khmer Rouge’s control of Cambodia. Amir talks about why the stele’s rediscovery was so important for the history of mathematics.