As the theme of the show revolves around science, many distinguished and high-profile scientists have appeared as guest stars on the show. Famous astrophysicist and Nobel laureate George Smoot had a cameo appearance in the second season. Theoretical physicist Brian Greene appeared in the fourth season, as well as astrophysicist, science populizer, and physics outreach specialist Neil deGrasse Tyson, who also appeared in the twelfth season.
Been watching the show for 12 years and it’s had ups and downs.I liked how they settled on an emotional ending,rather than a clever , so called cutting edge one.The elevator finally working was a nice touch.Sheldon’s big speech highlighted how much the characters have grown emotionally over the years and how much respect the actors have for each other.The people on this show always seemed to be having a good time performing.That was a big part of the pleasure the audience took in watching it.The final 2 episodes honored the things fans loved about the show.
Sheldon and Amy are surprised to find that Wil Wheaton's new Professor Proton show is actually very entertaining and that Wil had Howard on as a guest. On Howard's suggestion, Sheldon apologizes to Wil, mending their friendship, and tells him he wants to be on the show; but Wil asks for Amy. Sheldon tells her to do it, but she says she often doesn't do things to avoid upsetting him. Sheldon is horrified when he realises how selfish he has been, especially when he finds out that the men do the same for him. Sheldon encourages Amy to go on the show to inspire girls to pursue science while trying to control his obvious jealousy for her. Meanwhile, Leonard writes a book about a physicist that solves a murder, the protagonist Logan Dean is based on himself. Bernadette points out Logan's mean boss Illsa is similar to Penny, who thinks it is based on Bernadette, though Leonard does not correct her. However, Bernadette tells Penny the truth, upsetting her and making her mad at Leonard. After calling his mother for advice, Leonard learns that Illsa is actually like her; but abandons the book when he realizes he wrote romantic tension into the relationship between the characters.