The Solitude of Prime Numbers (original title: La solitudine dei numeri primi ) is a novel by the Italian author Paolo Giordano, published in 2008. It won the 2008 Strega Prize.[1] A cinematic adaptation of the novel was directed by Saverio Costanzo and released in 2010.
The novel narrates the childhood and early adulthood of a boy and girl who were each exposed to traumatic situations that followed them into adulthood. Both are outsiders, similar to how prime numbers are outsiders in relation to the other numbers. They befriend each other, forming a special relationship – becoming very close but never romantic. Their relationship appears to have run its course, but circumstances bring them together again and while they clearly love each other, they are unable to express their emotions. This relationship is compared to prime pairs: always together, but never touching.
Although the setting is never mentioned explicitly, references to Gran Madre Church, the Basilica of Superga, the Maria Ausiliatrice hospital, and to Fraitève and Monte Fraiteve identify the locale as Turin.
As a seven-year-old girl, Alice Della Rocca is forced by her father to take skiing lessons, although she hates the ski school and has no particular aptitude for the sport. One morning, Alice is separated from the rest of the group and falls off a cliff, sustaining serious injuries. Alice will remain crippled for the rest of her life.
Mattia Balossino is a gifted and intelligent child, unlike his twin sister Michela, who has a intellectual disability. Isolated from the rest of his peers because of his uncomfortable sister, Mattia lives his childhood in solitude. When he and his sister are invited to a classmate's birthday party, Mattia leaves Michela in a park so he can attend the party without her. Upon his return to the park a few hours later, Michela has disappeared, perhaps drowned in a nearby pond, and is never found despite a police search and investigation.
These events deeply affect the lives of both Alice and Mattia. During adolescence, Alice suffers from anorexia nervosa and is snubbed by boys as a cripple. With no social life, Alice draws the attention of Viola Bai, a popular but cruel girl in her class, who toys with Alice and briefly allows Alice into her circle of friends. With Viola's encouragement, Alice meets Mattia. Mattia is difficult to get along with; he is not interested in social interactions and has an unhealthy tendency to cut himself.
Alice and Mattia form an unusual friendship: each of them carries on with their own lives; however they return to look for one another. They continue to "date" even after high school. Both attend a university, where Mattia studies mathematics, and where Alice drops-out to pursue her passion for photography. When Alice's mother Fernanda is hospitalized for cancer treatment, Alice meets Fabio Rovelli, a young doctor who takes an interest in her. Mattia, meanwhile, completes his degree and receives an offer to teach at a university in Northern Europe (probably in Norway). While he is debating whether to leave Italy and take the job, Mattia finally tells Alice about Michela, and the two kiss for the first time. However, an argument between them convinces Mattia that leaving is the right decision. Later, Fernanda dies and Alice marries Fabio, while Mattia lives alone abroad.
The marriage between Fabio and Alice gradually disintegrates. Fabio wants a child, but Alice, who hasn't menstruated for years because of anorexia, cannot get pregnant and refuses to change her eating habits. The couple separates and Alice falls into depression.
Elsewhere, Mattia is a successful mathematics professor at his foreign university. He and Alberto, a colleague and fellow Italian, make an important discovery regarding algebraic topology. When celebrating at Alberto's house, Mattia meets Alberto's friend Nadia, and spends the night with her. Back in Italy, the photographer employing Alice insists on driving her to the hospital to get help for her depression. While there, she encounters an apparently disabled woman who looks a lot like Mattia, and Alice wonders if it could be Michela. She writes to Mattia, urging him to come home without telling him why.
Mattia accepts the invitation and returns to Italy. Alice, now unsure about what she saw, avoids telling him why she asked him to come. The two friends spend an afternoon together during which she kisses him and realizes that she's still in love with him. In spite of this, they both realize they cannot overcome the walls that separate them.