Sheldon attempts various tactics to change Leonard's mind, including bribery with "Frodo-shaped pancakes," citing roommate clauses, and even presenting a PowerPoint to Penny on why she shouldn't go.
Leonard ultimately travels to Switzerland with Raj , who is thrilled to enjoy the romantic amenities—like champagne and chocolates—originally intended for Penny. Key Characters & Cast [S3E15] The Large Hadron Collision
is the 15th episode of the third season of The Big Bang Theory , which originally aired on February 8, 2010. In this Valentine's Day-themed episode, Leonard is invited to visit the Large Hadron Collider in Switzerland and must choose between taking his girlfriend, Penny, or his roommate, Sheldon. Plot Summary Sheldon attempts various tactics to change Leonard's mind,