The Solo Oscillation Season 11, Episode 13 -  Aired January 11, 2018

The Solo Oscillation

After Sheldon decides to work solo without Amy, she turns to Leonard to work together on a series of science experiments. Meanwhile, geologist Bert replaces Howard in Footprints on the Moon, while Sheldon gets an unexpected source of scientific inspiration from Penny.

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Guest Stars: Laurie Metcalf as Mary Cooper, Brian Posehn as Bert, Pamela Adlon as Halley (O.S.)

Writers: Chuck Lorre (Story), Steve Holland (Story), Anthony Del Broccolo (Story), Eric Kaplan (Teleplay), Maria Ferrari (Teleplay), Jeremy Howe (Teleplay)

Director: Mark Cendrowski

Viewers: 15.93 million Households Rating: 10.2/17 Adults 18-49 Rating: 3.1/12

Available on iTunes

Episode Notes

  • The title refers to Sheldon's decision to work alone, without Amy, only to start getting inspiration from Penny.

> Footprints on the Moon

When Howard has to drop out of the band ahead of a gig, Raj recruits geologist Bert to join "Footprints on the Moon". Bert brings his own geology-inspired song about Indiana Jones, told from the perspective of the boulder that chases him. After Howard returns to the band, the newly-formed trio play at a Bar-Mitzvah and perform Bert's song.

> Sheldon's Knock

When Penny returned home to hear Leonard and Amy still working together in their apartment, she went over to 4B to see Sheldon.

After Penny performed Sheldon's characteristic knock on the door, calling his name, he responded "It's annoying when you do it."

Episode Quotes

Howard: (singing) Alone in my temple in the middle of Peru, A giant stone ball with nothing to do,
Raj: But if you steal my idol, I will roll right over you
All: Cause I'm six tons of granite, And micaceous schist. Yeah, I'm six tons of granite, And micaceous schist,
Bert: I'm gonna crush you, I'm gonna mush you, You took my idol, I'm homicidal, Gonna roll over you till your brains come out, And your bones will crunch and your blood will spout! I'm not just a rock, baby. I'm a boulder.
All: Cause I'm six tons of granite, And micaceous schist. Yeah, I'm six tons of granite, And micaceous schist, Yeah, I'm six tons of granite-

Howard: What up, my Hebrews and She-brews?!

Leonard: Thought you were getting us dinner.
Penny: Sorry. I had to stop at Sheldon's and help him solve string theory.
Amy: What?
Penny: Yeah, turns out the answer's knots.
Leonard: That's cute, but you can't have knots in more than four dimensions.
Penny: Mmm ... you can if you consider them sheets. [chuckling] Good night.

Mary Cooper: Oh, Shelly. I have bad news. Mr. Watkins passed this morning.
Sheldon: Oh. Oh, I'm-I'm sorry.
Mary Cooper: I know. What are the odds of that?
Sheldon: Call you back.

Sheldon: One thing you can't get on an iPad, the smell of ink and paper. One more reason iPads are better.

News Stories

Title Date Posted
1113 'The Solo Oscillation' Press Release December 22, 2017

CBS has issued the press release for the January 11 episode of The Big Bang Theory, "The Solo Oscillation". Laurie Metcalf reprises her role as Sheldon's mother, Mary, and Brian Posehn returns as Bert in the episode.  Full story


As the gang eat dinner in the apartment, Raj arrives with a gift for everybody: newspapers featuring a mention of his show at the planetarium. As the group struggle to unfold the newspapers and locate the item, Penny starts making a boat with her newspaper. Amy takes the opportunity to mention that the work she and Howard are doing was recently noted in a scientific journal. After Leonard mentions his latest work with Bert, Sheldon gets defensive when Leonard asks what he’s working on. Penny shows off her paper boat, which can also function as a hat.

When Sheldon and Amy return to the apartment, she asks if he wants to admit something’s bothering him or keep pretending it isn’t. Sheldon admits he blew up at Leonard earlier because he isn’t working on anything at the moment, conceding he has nothing interesting to pursue. Amy assures him he will find something he is excited about if he takes a little time to refocus. Later, Amy goes across the hall after Sheldon kicked her out to give him space to work. Leonard and Penny invite her in as they’re about to watch TV, but first Amy grosses them out by flushing her sinuses in the kitchen sink.

At Howard and Bernadette’s house, he and Raj are setting up their musical gear in the living room, practicing for an upcoming gig as Footprints on the Moon. When they start playing, Bernadette, who is still on bed rest, yells at them over the baby monitor to keep it down as Halley’s napping. After they start playing quietly, Halley wakes up and begins crying. Howard goes to change her, but Bernadette reminds him to bring diapers - so he heads out to buy some as he was supposed to have done already.

Back in his apartment, Sheldon comes out of the bedroom with stationery to get brainstorming new ideas for him to research. As he sits down at his laptop, he is interrupted by a phone call from his mother, who wants to tell him about somebody she just ran into. Sheldon says he’s too busy to speak and hangs up the phone. After he when goes over to his whiteboard, he starts by choosing an letter for unknowns in an equation before he quickly changes his mind. Abandoning the limited work he’s achieve, he then goes back and calls his mother to ask who she ran into. After she tells him it was Mr. Watkins, he’s unimpressed as it’s totally plausible, so he once again hangs up. He tries again to get back to work, but insteads calls his mother to discuss her encounter with Mr. Watkins.

As Leonard and Raj sit down at a table in the university cafeteria, Raj asks Leonard if he did anything fun last night. Leonard explains that after Amy came over, they bonded over their shared history in spelling bees. After Howard arrives, Raj asks if he is still on for band practice that night. Howard admits he forgot and has already promised to take Halley to Bernadette’s parents. Howard tells Raj he hates to say it, but he just doesn’t have the time to be in a band. After Raj says they will have to cancel the gig, Howard says he doesn’t want to break up the band so R should consider replacing him. Raj quickly agrees to drop Howard and decides to invite Bert, who plays the guitar, to join the band.

Back in the apartment, Leonard and Amy are performing a science experiment together on the kitchen table. When Penny arrives home, she is surprised that Amy is there again. After Penny asks about what they are doing, they explain it’s an experiment to make hot ice that they both did at science fairs in the ninth grade. When they mention doing another one experiment by building a cobra wave,  Penny is unhappy about the prospect. Leonard says they can do something they will all enjoy instead, but Penny tells them to do their experiments and she’ll go pick up dinner.

Across the hall in Sheldon and Amy’s apartment, he is working on a calculation on his whiteboard and is surprised when he actually arrives at a number. Sheldon calls his mother to tell her the answer is 1 in 18m, explaining that it’s the probability of her running into Mr. Watkins. Mary breaks some bad news, saying that Mr. Watkins passed away that morning. After she wonders what the odds of him dying after she just ran into him are, Sheldon says he’ll call her back.

As Penny climbs the stairs of the building, she hears Leonard and Amy still having fun as she reaches the apartment door. Instead of returning with dinner, she takes the pizza over to Sheldon’s apartment. Sheldon is grateful for the food as he’s been working hard and could use a break. When Sheldon explains what he’s been doing to Penny it’s clear it’s nothing but time-wasting nonsense. Sheldon blames people for distracting him from his work, but agrees to let Penny stay and eat as long as she is quiet.

In Raj’s apartment, he and Bert set up their equipment to practice for their upcoming gig. When Bert asks him if he wants to hear a geology song, Raj is initially unimpressed at the idea of a song about rocks. After Bert explains that it’s sung from the point-of-view of the boulder that chased Indiana Jones, Raj says the song is right up their alley.

Back in the apartment, Leonard and Amy are making a lattice out of popsicle sticks to explore ways to store kinetic energy. Amy takes the opportunity to ask Leonard a question: does it feel different to be married? When he replies “Not really”, he apologizes as he doesn’t think that was the answer she was looking for. Amy says it actually is as she and Sheldon are in a good place and she doesn’t want anything to mess that up.

In Apartment 4B, Penny is still eating pizza as Sheldon discusses the work he was considering. After Sheldon says he just wishes he could find something that excites him, Penny asks him what got him excited about dark matter in the first place. Penny argues that dark matter was his “rebound science” after he dumped string theory.

In their bedroom, Bernadette is asleep as Howard plays keyboard with headphones in bed next to her. Despite the lack of music noise, it’s still makes a racket and wakes up Bernadette. Howard tells her that by not being in a band, he can now focus on his solo career. Howard wants to write an astronaut musical and demonstrates his first song for Bernadette. Later, Howard goes to Raj’s apartment as he and Bert practice to tell them he’s back in the band; it was Bernadette’s idea.

Back in Apartment 4B, Penny sits at the kitchen counter while Sheldon tries to explain string theory to her. When she understands the concept, she asks if they’ve solved string theory. Sheldon says it’s not that easy; people have been stuck on it for decades. Penny argues it shouldn’t be that hard, after all that strings are simple: straight, in a loop, knotted up with other strings. Sheldon starts to tell her that strings can’t knot up in more than four dimensions, but he realizes they could if they were considered as sheets. And it only took Penny a minute to get to that revelation.

When Penny returns to Apartment 4A, Leonard and Amy are tidying up their popsicle sticks. After Leonard says he thought she was getting them dinner, Penny apologizes, saying she had to stop at Sheldon’s to help him solve string theory. After she explains that strings can be knotted in more than four dimensions if they’re considered as sheets, Penny goes to bed leaving Leonard and Amy bewildered.

As Howard, Raj and Bert play a bar mitzvah, they sing Bert’s song to a largely unimpressed audience.