David Saltzberg, a professor of physics and astronomy at the University of California, Los Angeles, checks scripts and provides dialogue, math equations and diagrams used as props. He says he is more consultant than contributor. Executive producer/co-creator Bill Prady said, "In fact, we're working on giving Sheldon an actual problem that he's going to be working on throughout the [first] season so there's actual progress to the boards ... We worked hard to get all the science right."