The Einstein Approximation

Summary
Sheldon's search for the answer to a physics problem (why electrons behave as if they have no mass when travelling through a graphene sheet) keeps him up all night for several days and he becomes obsessed with figuring out the solution. One attempt in a mall ballpit has Leonard jump in and try to get Sheldon out as he pops in and out, shouting "Bazinga!". He then decides that he needs a menial job to think better because Albert Einstein came up with the Theory of Relativity while working a menial job at the Swiss Patent Office. Since the American patent office is in Washington DC, and he doesn't want to move out of Pasadena, he interviews for any menial job with the County of Los Angeles, where he is interviewed by a woman named Sandy (played by Yeardley Smith, famous for the role of Lisa Simpson, in "The Simpsons"). Since he is tossed out, the next menial job he can think of is to work at the Cheesecake Factory with Penny. He shows up and works as a busboy and waiter, but never is actually hired. After dropping and breaking a tray of dishes, he discovers the answer to his problem, and promptly walks out, without cleaning up the mess. This results in Leonard trying to find Sheldon in the ballpit again.

Meanwhile Raj, Leonard, Penny, Howard, and Bernadette all go to disco night at the roller skating rink. The guys embarrass the girls with their outfits and dancing.

Title reference: Sheldon's attempt at solving his problem by working in a menial job, comparing it to Albert Einstein's discoveries made while working in Switzerland in the Patent Office.

Quotes
Sandy: So, Mr. Cooper, you're looking for a job.

Sheldon: A menial job. Like yours.

Sandy: Why, thank you for noticing. I'm "Menial employee of the month". Do you have a particular field in mind?

Sheldon: I do. For thousands of years the lowest classes of the human race have spent their lives laboring to erect monuments under the lash of their betters, until finally they dropped down, and became one with the dust through which they trudged. Do you have anything like that?

Sandy: No.

Sheldon: Shouldn't you check your database?

Sandy: [pretends to be typing on her keyboard] No.

Sheldon: You didn't really type.

Sandy: I didn't really have to. So, how about construction?

Sheldon: Oh, that would be good! Sawing, hammering, eating out of a lunch pail as my working-class fellows and I sit perched precariously on a girder high above the metropolis.

Sandy: No, no. This is putting up sheetrock at a housing project in Rosemead.

Sheldon: I could do that.

Sandy: Good.

Sheldon: One question?

Sandy: Yes?

Sheldon: What's sheetrock?

Sandy: ...Moving on. How about doing deliveries for a florist?

Sheldon: That seems acceptable.

Sandy: Do you have your own car?

Sheldon: I don't drive.

Sandy: Of course you don't. Mr. Cooper, let me just ask you a question. What was your last job?

Sheldon: Senior theoretical particle physicist at Caltech, focusing on M-theory, or, in layman's words, string theory.

Sandy: I see. Just give me a second. [Walks off-screen] [Shouts]: SECURITY!

Trivia

 * At his official 2010 Nobel Prize acceptance lecture in Stockholm, Dr. Konstantin Novoselov showed graphene, and Sheldon from this episode.
 * There are numbers on some of the balls in the ballpit.