Ep 7. The Proton Displacement

In The Big Bang Theory season 7 episode 7, titled "The Proton Displacement," the gang prepares for science professor Proton's (played by guest star Bob Newhart) visit to the university, but when Sheldon is dismissed from guiding the professor, Leonard, Howard, and Raj compete to be Proton's new teaching assistant.

Sheldon is initially tasked with taking care of Professor Proton but is fired due to his disrespectful manner. This leads Leonard, Howard, and Raj to vie for the open teaching assistant position. They all want to impress the distinguished Professor Proton, but when they learn that he likes to drink, they try to take him to a bar, where they have to dodge Sheldon, who has followed them in order to make amends. Nevertheless, the trio succeeds in getting Professor Proton drunk and proceeding to a bar.

At the same time, Bernadette is a bit worried about leaving Halley with Stuart. She is hesitant to leave her baby girl alone with Stuart as she is unsure of his abilities to take care of a baby. As a result, she decides to test him and leaves him with a baby doll, only to find that Stuart actually proves to be a dependable babysitter.

The episode ends with Sheldon visiting Professor Proton's office and apologizing for his behavior and asking to be reinstated. Professor Proton responds by advising Sheldon on how to be a better friend to his peers while providing him with guidance on how to conduct himself in a more amiable manner.

Overall, "The Proton Displacement" is a lighthearted episode where the audience gets to see the gang compete in a friendly battle for the top teaching assistant position. There are elements of comedy, the usual workplace antics, and a focus on character development, making it an excellent episode for fans of the show.