The scientists who came up with the theory of supergravity in the 1970s are $3 million richer.

The trio, physicists Sergio Ferrara, Daniel Z. Freedman and Peter van Nieuwenhuizen, won the Special Breakthrough Prize in Fundamental Physics, according to a statement Wednesday.

Supergravity is described in the prize announcement as a theory in which, “quantum variables are part of the description of the geometry of spacetime.”