Dianna Cowern

Dianna Cowern (born May 4, 1989) is an American science communicator and physicist, who has run the YouTube channel Physics Girl since its inception in 2011. Her videos explain physical phenomena in everyday life, using an informal, fast-paced style. The series was produced in partnership with the PBS Digital Studios from 2015 until 2020.

Cowern started Physics Girl in 2011 after graduating with a bachelor's degree in physics from the Massachusetts Institute of Technology. After winning a 2014 video competition from the Alan Alda Center for Communicating Science, the series started being produced by PBS Digital Studios, whereupon she began working on content creation full-time. Cowern won Best Web Personality at the 2018 Webby Awards and was included in the 2019 Forbes 30 under 30. She developed long COVID in July 2022, becoming housebound and unable to produce videos until 2026.