The Big Bang Theory premiered in the United States on September 24, 2007 on CBS. The series debuted in Canada on CTV in September 2007. On February 14, 2008, the series debuted in the United Kingdom on channels E4 and Channel 4. In Australia the first seven seasons of the series began airing on the Seven Network and 7mate from October 2015 and also gained the rights to season 8 in 2016, though the Nine Network has rights to air seasons nine & ten. On January 22, 2018, it was announced that Nine had acquired the rights to Season 1–8.
As Sheldon and Amy start to plan their wedding, they use decision theory to limit the stress of choosing between their competing visions for the big day. After they begin to question each other’s decisions and make deliberately provocative choices, they decide to have a simple wedding at City Hall. As they wait their turn, Sheldon changes his mind and decides he wants a first dance with Amy at a real wedding.
David Saltzberg, a professor of physics and astronomy at the University of California, Los Angeles, checks scripts and provides dialogue, mathematics equations, and diagrams used as props. According to executive producer/co-creator Bill Prady, "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." David Saltzberg, who has a Ph.D. in physics, has served as the science consultant for the show for six seasons and attends every taping. He sees early versions of scripts which need scientific information added to them, and he also points out where the writers, despite their knowledge of science, have made a mistake. He is usually not needed during a taping unless a lot of science, and especially the whiteboard, is involved.
When Leonard receives a braggy Christmas letter from his brother, he feels bad about how little he and Penny have achieved in the past year. Leonard wonders if he and Penny should be thinking about the next step after two years of marriage, like buying a house or having a baby. Penny tells him she wants to do all those things someday, but she has a bunch of stuff she would like to do first.