Профессордың сүйікті теңдеуі

Novel by Yōko Ogawa

The Housekeeper and the Professor (博士の愛した数式) (literally "The Professor's Beloved Equation") is a novel by Yōko Ogawa set in modern day Japan. It was published in Japan in August 2003, by Shinchosha. In 2009, the English translation by Stephen Snyder was published.

The story centers around a mathematician, "the Professor," who suffered brain damage in a traffic accident in 1975 and since then can produce only 80 minutes' worth of memories, and his interactions with a housekeeper (the narrator) and her son "Root" as the Professor shares the beauty of equations with them. The novel's bibliography lists the book The Man Who Loved Only Numbers, a biography of the mathematician Paul Erdős. It has been said that Erdős was used as a model for the Professor. The novel received the Hon'ya Taisho award, was adapted into a film version in January 2006, and after being published in paperback in December 2005, sold one million copies in two months, faster than any other Shinchosha paperback.

The narrator's housekeeping agency dispatches her to the house of the Professor, a former mathematician who can remember new memories for only 80 minutes. She is more than a little frustrated to find that he loves only mathematics and shows no interest whatsoever in anything or anyone else. One day, upon learning that she has a 10 year old son waiting home alone until late at night every day, the Professor flies into a rage and tells the narrator to have her son come to his home directly from school from that day on. The next day, her son comes and the Professor nicknames him "Root". From then on, their days begin to be filled with warmth.

The novel was the inaugural winner of the Hon'ya Taishō Award. A review for the Japan Times wrote: "Ogawa gently unfolds an elegant, charming equation for success, leaving the reader to muse about loss, memory and the magic of mathematics." The novel was also praised outside of Japan. Dennis Overbye, writing for the New York Times, called it a "deceptively elegant" novel. Kirkus Reviews gave a positive review, writing the novel "deftly balances whimsy with heartache" and ultimately calling it a "simple story, well told". The New Yorker gave a mixed review, writing that although there were some touching scenes, the relationship between the housekeeper and the professor never built up to any great revelations.

A film based on the novel was released on January 21, 2006. It was directed by Takashi Koizumi. In contrast to the original work, which is told from the perspective of the narrator, the film is shown from the perspective of 29 year old "Root" as he recounts his memories of the Professor to a group of new pupils. Though there are a few differences between the film and the original work (for example, the movie touches on the relationship between the Professor and the widow, while the book does not give much detail), the film is generally faithful to the original.