The last sentence of the English translation of the conversation between the two chinese geeks is not correct.
At the question "who is doing that" the 'chinese Sheldon' answers: "ige ren jiao Pasadena california zong Wolowizard" which means "a guy called Pasadena, California from Wolowizard".
In this episode Leonard reveals he got his doctorate at age 24, while Sheldon got his at age 16.
The video of Sheldon and Leonard fighting that the guys watch on YouTube is different than what actually happened. When it actually happened Sheldon said "heads up, you people in the front row, this is a splash zone." On the video, Sheldon says "you people in the front row, heads up, this is a splash zone." Also on the video, right after Sheldon's line Raj looks at Howard's camera even though when it actually happened he clearly did not look at the camera.
Leonard states to Penny while going through his closet that he had only one tie, the reversable one, but in "The Hamburger Postulate", a different tie hangs on Leonard's door knob with a completely different pattern.
Leonard: You are not Isaac Newton.
Sheldon: No, no, that's true. Gravity would have been apparent to me without the apple.
Leonard: Sheldon, why is this letter in the trash?
Sheldon: Well, there's always the possibility that a trash can spontaneously formed around the letter, but Occam's Razor would suggest that someone threw it out.
Leonard: (watching their fight on YouTube) Oh, geez, does this suit really look that bad?
Sheldon: Forget your suit. Look at my arms flailing. I'm like a flamingo on Ritalin.
(at the mailboxes)
Penny: Get anything good?
Sheldon: Just the latest copy of Applied Particle Physics Quarterly.
Penny: Oh, you know, that is so weird that yours came, and mine didn't.
Leonard: Are there any other honors that I've gotten that I don't know about? Did UPS drop off a Nobel Prize with my name on it?
Sheldon: Leonard, please don't take this the wrong way, but the day you win a Nobel Prize is the day I begin my research on the drag co-efficient of tassles on flying carpets.
Koothrappali: I don't want to be in a jar. I want my brain in an android body—8' tall and ripped.
Wolowitz: I'm with you, I just have to make sure if I'm a synthetic human, I'd still be Jewish. (Sheldon and Koothrappali stare) I promised my mother.
Penny: Howard, would you like to explain to me why your Facebook page has a photo of me sleeping on your shoulder captioned, "Me and My Girlfriend"?
Penny: So, you know, isn't there maybe some way you and Sheldon could compromise on this whole presentation thing?
Leonard: No. Scientists do not compromise. Our minds are trained to synthesize facts and come to inarguable conclusions. Not to mention Sheldon is bat-crap crazy.
Leonard: My name is Dr. Leonard Hoftstadter, and I could never please my parents so I need to get all my self-esteem from strangers like you. (points to Sheldon) But he's worse!
Penny: So, you and Leonard.
Sheldon: Oh, dear God.
Penny: Little misunderstanding, huh?
Sheldon: A "little misunderstand—?" Galileo and the Pope had a "little misunderstanding".
Wolowitz: I just checked the house. There's probably 20, 25 people in there.
Leonard: You're kidding!
Penny: Is that all?
Leonard: "All?" In particle physics, 25 is Woodstock.
Leonard: Sheldon, we have to do this.
Sheldon: No, we don't. We have to take in nourishment, expel waste, and inhale enough oxygen to keep our cells from dying. Everything else is optional.
The German episode title is "Der Cooper-Hofstadter-Antagonismus". The French title is "La Polarisation Cooper-Hofstadter". The Italian title is "La polarizzazione di Cooper e Hofstadter". The Spanish and Mexican title is "La polarización de Cooper-Hofstadter".
International Airdates: Turkey: November 11, 2008 on CNBC-e; Czech Republic: June 2, 2009 on Prima COOL; Germany: August 29, 2009 on ProSieben; Slovakia: August 30, 2011 on Markiza
The video that Wolowitz posts to YouTube in this episode was, in fact, posted on March, 11 2008 by the user 'Wolowizard', and is available to view.
This episode's end titles has Chuck Lorre's Vanity Card #196.
Beginning with this episode, the series moves to 8:00, trading time slots with How I Met Your Mother.
Originally scheduled for November 19, 2007, this episode was delayed by the WGA strike that started two weeks prior.
When Penny asks Sheldon how he feels and he responds, "I don't understand the question," is a play on Spock's interplay with a Vulcan examination computer and his mother in Leonard Nimoy's 1986 film Star Trek IV: The Voyage Home.
The imagery of the guys beating their chests as Strauss' Also Sprach Zarathustra plays is an homage to Stanley Kubrick's 1968 film 2001: A Space Odyssey.
The "little misunderstanding" Sheldon refers to the Pope and Galileo having involves Galileo championing Copernicus' theory that the earth circled the sun, in direct opposition to the Catholic Church's official teaching that the earth was the centre of the universe.