[David Saltzberg] got involved with The Big Bang Theory in 2007, when the show was little more than a theoretical construct. The set designers asked him to show them some real graduate students' apartments, so they could see how young scientists really live.
"And they did a nice, faithful re-creation of their apartments," he said, adding that after CBS tested the show, the sets were scrapped, because, Saltzberg thinks, the sets were too depressing.