The Big Bang Theory Season 7 Episode 1
The Hofstadter Insufficiency
Leonard is still on the ship doing research ... or drinking and partying it up it seems. Sheldon and Penny both miss him and hang out to ease their sadness. They get upset when they find out that Leonard is having a blast and doesn't seem to miss them at all.
Amy and Bernadette are away at a work conference. They appreciate that they can talk about intellectual topics instead of boys because Penny's not there. They get excited when a couple guys buy them drinks, but then get in a fight over their significant others. In the end, they make up.
Raj isn't dealing with his breakup from Lucy well. Howard suggests that he go to a party for post-docs. Raj ends up insulting Mrs. Davis and then connecting with her when he goes to apologize.