Erik Selvig is an astrophysicist and he taugh Jane Foster and Darcy Lewis. Selvig is a Professor of Theoretical Astrophysics at Culver University. His notes on thermonuclear astrophysics help S.H.I.E.L.D. understand the Tesseract. Selvig is in fact, placed under mind control by Loki in the Avengers. Loki has Selvig build a portal into space using the Tesseract's power. After this happens, Selvig's brilliant mind is left a little scrambled.