The Electric Can Opener Fluctuation

Synopsis
Following his return from the Arctic, Sheldon is very excited over the prospects that his research in the Arctic has yielded, whereas Raj, Howard, and Leonard couldn't believe they spent three months in the Arctic and are just glad to be home. Penny is happier than most that Leonard has returned and passionately kisses him when he knocks on her door.

The revelation that the data that Sheldon gained was false (and achieved static magnetism by the electric can opener), learning that his friends hated him being in charge, Penny attempting to comfort Sheldon and being ridiculed by Barry Kripke, Sheldon runs away from home back to Texas, to his mother.

Meanwhile, Penny and Leonard try and hook up, but Leonard can't seem to catch a break, first being interrupted by Sheldon finding out about the lies and the next time by Sheldon running away.

At his mother's home, Sheldon becomes increasingly annoyed by his mother's overly Christian beliefs and the boys go to Texas to try and bring Sheldon home. Eventually, it's Sheldon's mother that drives Sheldon home following her stubbornness about not believing in evolution.

Back at home, Penny and Leonard finally hook up, but both of them now feel their relationship got weird.

Quotes

 * (Leonard, Howard and Raj are at Sheldon's mother's place in Galveston, Texas, trying to get Sheldon to come home with them. Howard is wearing a goofy cowboy hat and a moustache. Leonard rings the doorbell.)
 * Leonard: Can you please take that stupid hat off?
 * Howard: No, I wanna blend in.
 * Raj: To what, Toy Story?
 * (Leonard chuckles at Raj's remark. Mary Cooper opens the door.)
 * Mary: Hi, boys.
 * Howard (with Texan accent): Howdy, Ma'am.
 * Mary: Howdy to you too, you got here quick.
 * Leonard: Ah, we took the Red Eye.
 * Mary: Well come on in.
 * Howard (with Texan accent): Thank you kindly.
 * Mary: Can I, can I get you something to drink?
 * Leonard: Uh, no, thank you.
 * Howard (with Texan accent): Uh, if ya'll don't mind, I'm hankering for a Lone Star Beer.
 * Mary: There's no alcohol in this household, stop talking like that and lose the hat.
 * Howard (In normal voice): Sorry, I'll take a Diet Yoo-hoo if you have it.
 * Mary: You'll take a coke. (To Raj) What about you, Raj, is it? Oh you still having trouble talking to the ladies? (chuckles) Because you know at our church, we have a woman who's an amazing healer. Mostly she does, uh, crutch and wheelchair people, but I bet she'd be willing to take a shot at whatever third world demon is running around inside of you.
 * Leonard: Uh, if you don't mind, Mrs. Cooper there's a 3:05 non-stop back to Los Angeles and you have no idea how much I wanna be on it.
 * Mary: A girl?
 * Leonard: Uh, yes ma'am.
 * Mary: Good, I've been praying for you.
 * (Sheldon walks into the room.)
 * Mary: Oh. Sheldon.
 * Sheldon: What are they doing here?
 * Leonard: Uh we came to apologize.
 * Howard: Again.
 * Leonard: And bring you home, so why don't you pack up your stuff and we'll head back.
 * Sheldon: No. This is my home now. Thanks to you, my career is over. And I will spend the rest of my life in Texas, trying to teach evolution to creationists.
 * Mary: You watch your mouth, Shelly. Everyone's entitled to their opinion.
 * Sheldon: Evolution isn't an opinion, it's fact.
 * Mary: And that is your opinion.
 * Sheldon (To the guys): I forgive you, let's go home.
 * (Goes to pack his stuff.)
 * Mary: Don't tell me prayer doesn't work (continues drinking her Diet Pepsi).

Science

 * Sheldon's experience was to track slow moving magnetic monopoles at the magnetic North Pole.

Culture

 * Sheldon believes his work on Magnetic Monopoles will gain him a Nobel Prize.
 * Howard and Leonard makes reference that Sheldon has "Vulcan hearing".
 * Sheldon makes reference to emoticons (himself being :D, then Raj noting he became :O following the revelation).

Trivia

 * This is the first episode to have a recap (voiced by Penny) of previous episodes.
 * Penny described a scene from the movie Star Trek in this episode, meaning she probably saw it even though the others didn't, which could indicate that she has begun to like their nerdy things. This was the only time she knew something about Star Trek that Sheldon didn't.
 * Sheldon's beard looks like the one Spock has in the "mirror universe". Along with that, Howard and Leonard mention about his Vulcan hearing.
 * When Howard says to Mary he'll take a Diet Yoohoo, in the DVD, she says he'll take a coke, but on T.V., she says he'll take a cola.
 * Raj suggests Howard's hat is reminiscent of Woody's in Toy Story. Laurie Metcalf (who plays Mary Cooper) is in all three Toy Story films.