Randall Carlson is an American house builder and designer, and a geological and anthropological theorist. Raised in Freemasonry since 1979, beginning his studies in 1969. He is a proponent of the Younger Dryas impact hypothesis and has theorized about the extinction of historical advanced human civilizations. Carlson founded Sacred Geometry International, which focuses on a range of controversial theories and has a website and Facebook page. Carlson’s theories have not been peer-reviewed or published in any scientific journals. He has often appeared on the Joe Rogan Experience podcast, sometimes accompanying Graham Hancock, who promotes similar ideas.