It’s hard to believe that the first episodes of The Big Bang Theory were released in the now distant year of 2007 — that was 11 years ago! Since then we’ve watched 250 episodes of this TV show which follows the lives of 4 physicists.
When Leonard meets Penny in the pilot episode and when Penny agrees to go out with him in episode 100 named “The Recombination Hypothesis”, she wears the same shirt!
Laurie Metcalf who plays the part of Sheldon’s mother in TBBT is also the mother of Zoe Perry who portrays the mother of young Sheldon in Young Sheldon the TV series. Jim Parsons can really play the theremin, Sheldon’s favorite musical instrument. And it’s quite surprising because this instrument which was invented in 1920 and named after the Westernized name of its Soviet inventor, Léon Theremin, is one of the most difficult to play. By the way, Johnny Galecki can play the cello, Mayim Bialik, the harp; and Simon Helberg, the piano.
The words to the famous lullaby Soft Kitty were written by an Australian teacher named Edith Newlin in the 1930s. Her daughters filed a lawsuit against the various companies associated with The Big Bang Theory for violating the copyright laws. The song was used in the TV series thanks to producer Bill Prady’s daughter who heard this lullaby in her kindergarten class. Leonard’s glasses don’t have lenses in them. According to Johnny Galecki, since Jim Parsons was much taller than him, he had to always look up. The light from the projectors reflected off his glasses and created a glare. Throughout many episodes, Penny appears with the same bag. But even when it changes, it looks almost the same as the previous one — it’s also made of brown leather and has an identical shape.
In the unaired pilot of The Big Bang Theory, Wolowitz and Koothrappali didn’t exist, while Penny and Leslie Winkle’s parts were portrayed by other actresses. In addition to that, Penny’s name was Katie then.
The house where Sheldon and Leonard live has only one staircase and one landing. Every time the characters were taking the stairs to their floor, the shooting crew just changed the look of the doors. Raj’s apartment and Howard and Bernadette’s house never appear in the same episode because both the apartment and the house are the same set.