Mathematician Zvezdelina Stankova was born in Bulgaria and is now a teaching professor at UC Berkeley. Zvezda's webpage - https://math.berkeley.edu/~stankova/ Zvezda videos on Numberphile - https://www.youtube.com/playlist?list=PLt5AfwLFPxWIbAPK1oJgRIpe0sWiPKkQ4 The Legend of Question Six - https://www.youtube.com/watch?v=Y30VF3cSIYQ Berkeley Math Circle - https://mathcircle.berkeley.edu This episode was supported by G-Research, a world-leading quantitative finance research firm, hiring the brightest minds to tackle the biggest questions in finance - learn more at gresearch.co.uk/numberphile/ - https://www.gresearch.co.uk/numberphile/ You can support Numberphile on Patreon - https://www.patreon.com/numberphile Like these people - https://www.numberphile.com/patrons With thanks to MSRI - https://www.msri.org