# My Search for Ramanujan: How I Learned to Count

Ken Ono’s memoir speaks to anyone seeking inspiration regardless of their mathematical or academic interests

Sixteen-year-old Ono found himself with his father in his father’s study at their home one afternoon in 1984, after an unexpected letter from India from S. Janaki, Ramanujan’s octogenarian widow, arrived at their home. Ono first learned of Ramanujan’s story from his father that afternoon—little did he know at the time how profound an impact on his own life Ramanujan would have.

It’s almost a surprise—a welcome one—to encounter such a human story in the pages of My Search for Ramanujan: How I Learned to Count. It is a personal, mathematical, historical, and spiritual journey narrated by Ken Ono, Asa Griggs Candler Professor of Mathematics at Emory University. His co-author, Amir Aczel, who passed away before the completion of the book, was a best-selling author, lecturer, and science historian known for his works such as Fermat’s Last Theorem: Unlocking the Secret of an Ancient Mathematical Problem, and Finding Zero. My Search is part-autobiography, of Ono, and part-biography, of Srinivasa Ramanujan.

In Part I of this three-part book, Ono writes about his upbringing as a self-described awkward Japanese-American boy by “tiger parents”. The reader gains a sense of Ono as a child growing up in the suburbs of Baltimore, Maryland, who is placed under immense parental pressure not just to succeed, but to excel, in every aspect of his life. He paints the picture of a brilliant yet distant mathematician father—Takashi Ono, an esteemed professor of mathematics at Johns Hopkins University—and a wondrously reliable and dutiful mother, both of whom expect nothing less than perfection from each of their three children. Ono’s parents had immigrated from Japan to the United States following WWII in a story that he describes as a “fairytale”, yet, at the same time, one which is sadly tainted with elements of racism. This part of the book ends with a sixteen-year-old Ono first encountering the name Ramanujan via a letter sent to his father. As an adult, Ono reflects on just how profound an experience the letter and discussion with his father would turn out to be. In Part III, Ono discusses his difficult transition to college and path through adulthood, with the spirit of Ramanujan persisting throughout. Part II bridges Part I and Part III with Ramanujan’s story—equally heroic, tragic, phenomenal, fateful, and inspiring.

Ono’s father is the first of a handful of mathematicians discussed in My Search whose life, in various aspects, mirrors Ramanujan’s. Said another way, one sees the spirit of Ramanujan shining through Ono’s father in the early chapters of the book, with other mathematicians to follow, including Ono himself. I borrow the phrase “the spirit of Ramanujan” from Bruce Berndt’s book Number Theory in the Spirit of Ramanujan, as it captures a certain air about him that many agree Ramanujan had––and still has.

Says Ono:

Both [my father and Ramanujan] are self-taught creative geniuses. Both men escape poverty thanks to the generosity of a world-class mathematician who offers the opportunity to work with the world’s best in a foreign land. And both men are rewarded for their achievements despite the indignities and hindrances to success that they suffer due to racial prejudice.

Ono is referring to the fact that André Weil, the prominent French number theorist and algebraic geometer and one of the original leaders of the Bourbaki, was impressed by Takashi Ono (then a young graduate student) after meeting him at the Tokyo-Nikko conference in Japan in 1955. Weil arranged a two-year research position for Ono’s father at the Institute for Advanced Study in Princeton.

Ramanujan’s Weil is, of course, G.H. Hardy, the decorated English number theorist. Like the careers of Ono’s father and Ramanujan, Weil’s mathematical career too was affected by war (though this parallelism is not explicitly mentioned in My Search). Weil’s parents, Jewish but agnostic, fled Alsace-Lorraine for Paris after the Franco-Prussian War. Shortly after the outbreak of WWII, Weil fled France for the United States, supported by fellowships and various teaching positions, before making his way to the Institute for Advanced Study in the late 1950s.

The story of Ramanujan, who lived a short yet remarkable 32 years (1887–1920), is the common thread woven through the various themes of My Search. It is a story well-known to many. This includes, but is by no means limited to, mathematicians who continue to work on subjects in his wake today, nearly 100 years after his passing. As Ono describes, Ramanujan became something of a celebrity in India at a young age due to his mathematical prowess, and his invitation to England’s prestigious University of Cambridge, after a very humble upbringing in Kumbakonam. Ramanujan has since become a worldwide symbol of genius, his story known widely through popular works such as the biography The Man Who Knew Infinity: A Life of the Genius Ramanujan by Robert Kanigel (1991), and the novel The Indian Clerk by David Leavitt (2007). A screenplay of Kanigel’s book was written by Matt Brown, who directed a 2016 Hollywood film of the same name starring Dev Patel (“Slumdog Millionaire”) as Ramanujan, and Jeremy Irons (“Reversal of Fortune”, “Lolita”) as his mentor G.H. Hardy. Ono and Manjul Bhargava, R. Brandon Fradd Professor of Mathematics at Princeton University, worked as consultants and Associate Producers on the film, whose release coincided with that of My Search.

As Ono tells us in Part II of My Search, Ramanujan was a mathematical prodigy, born to a father who had little role in his upbringing, and a dominant mother whose primary role was to raise her children. Ramanujan excelled so greatly in school, that after earning a reputation as a math genius and winning awards and prizes throughout childhood, he won a scholarship to the well-regarded Government College in Kumbakonam. Mathematics seemed to have become more than just a passion of Ramanujan’s. After learning of G.S. Carr’s Synopsis of Elementary Results in Pure Mathematics, Ramanujan’s passion for and natural talent in mathematics seemed to turn into an obsession, or addiction, as Ono tells it. Carr’s Synopsis contains 6165 formulas and results, ranging from the elementary—such as $a^2-b^2=(a-b)(a+b)$—to the more sophisticated. The book contains few proofs, and as the story goes, Ramanujan spent countless hours with it, feeding his addiction. Losing interest in anything but mathematics, Ramanujan failed in English composition and lost his scholarship at Government College. This failure prompted him to run away from his life, literally, ending up 700 miles away in Visakhapatnam. Eventually his family found him, and Ramanujan resumed his studies at Pachaiyappa’s College in Madras (now Chennai). His addiction was not quelled however; he was forced to withdraw from college again, this time after failing his Physiology exam.

At this point in the book, the reader begins to see parallels between the lives of not just Ramanujan and Ono’s father, but also Ramanujan and Ono himself. Ono, too, was mathematically talented as a child. Based on unusually high SAT scores in sixth grade, young Ono was offered, but declined, a scholarship to attend Towson State University in Maryland the following year. Ono was also a subject of well-known Johns Hopkins psychologist Julian Stanley’s “Study of Mathematically Precocious Youth”. As a sixteen-year-old learning of Ramanujan’s story from his father, Ono recognized his father’s great respect for Ramanujan, a two-time college dropout. Eventually, the arguing between parents and child stopped, and Ono packed his bags for Montreal to join his older brother Santa, then a Ph.D. student in biochemistry and immunology at McGill University. Today, Santa Ono is President and Vice-Chancellor of the University of British Columbia. For Ono, dropping out allowed him to flee his “pressure cooker of a life” to Montreal, similar in some ways to Ramanujan’s escape to Visakhapatnam after losing his scholarship at Government College, and was an “escape [from] a frustrating and confusing life”.

After a number of months enjoying freedom and learning to live independently, Ono was accepted to and enrolled in the University of Chicago. Like Ramanujan, Ono was not a model college student; on his first college exam (honors chemistry) he received a C${}^+$, and on his first paper (sociology) he received an F. Academics were not Ono’s primary college interests at first—as he tells the reader, his social life, cycling, and fraternities, were. He later turned to mathematics, though his path to success was not without incident. For example, Ono recounts what a visiting professor told him in his junior year at Chicago:

He told me that he knew my father and that he felt compelled to tell me that from what he had seen of my work, I was unlikely to be successful as a professional mathematician… I was wasting my time chasing a hopeless dream.

Fortunately, this disturbing encounter fueled Ono to prove this professor wrong. Chicago professor Paul Sally (who some might say followed a somewhat indirect path into academia as a high school basketball star, and by briefly working as a taxi driver) later recognized the opposite of what the visiting professor felt—Ono was one of the best students in his difficult course in Honors Analysis. Sally’s mentoring ultimately convinced Ono to apply to graduate school, and months later he enrolled in UCLA.

Other mentors after Sally would have a deep impact on Ono’s career, including his Ph.D. advisor at UCLA, Basil Gordon, and also Andrew Granville, a highly regarded English number theorist (now at the University of Montreal) who Ono went to work with at the University of Georgia after graduate school. Ono describes Granville as his “own personal G.H. Hardy”. Now many years later, Ono is himself a prominent number theorist and a mentor to many; he has won numerous awards and prizes including a Sloan Fellowship, a Packard Fellowship, a National Science Foundation CAREER Award, a Presidential Early Career Award (awarded by President Bill Clinton), a Guggenheim Fellowship, and more. In My Search, Ono recognizes the importance of his mentors––something he has also taken to heart and reflected back to the community in the 23 years since he graduated from UCLA. Ono has advised a remarkable 14 postdocs, 25 Ph.D. students—aside from the seven he is currently advising—and scores of undergraduates.

Ramanujan’s strong relationship with his mentor Hardy was also critical for his success. However, his path to success, like Ono’s, was not wholly smooth. The Circle Method, his work on the partition function, his mock theta functions, and countless other mathematical results of Ramanujan’s are to this day remarkable. However, it took some time for his work to be recognized by Hardy, and then by people beyond Hardy’s immediate circles in the larger mathematical community. Ramanujan failed to be elected as Fellow of Trinity College the first time he was nominated. Circumstances related to WWI were a contributing factor to this failure, as was racism; one Fellow explicitly said he would “not have a black man as a Fellow”. Ramanujan later attempted suicide by throwing himself in front of a train, but was saved by an operator. The tables finally turned when Ramanujan was elected Fellow of the Royal Society in 1918, then to the London Mathematical Society, and, finally, as Fellow of Trinity College. In My Search Ono confesses his own suicide attempt, which occurred when he was a 24-year-old graduate student, after a professional “disaster” in Minnesota. Like Ramanujan’s, his life was spared—in Ono’s case by his own last minute choice to swerve his car out of the path of an oncoming logging truck.

Ono reflects on how Ramanujan has been a source of not just mathematical but also personal inspiration. Today, Ono himself is an inspiration to many

Fast forward a few years, and Ono will be in a very different place in life, having proved his famous theorems on Ramanujan partition congruences, among others, having earned a stay at the Institute for Advanced Study, and also having made substantial contributions to harmonic Maass forms, the theory of which encompasses Ramanujan’s original mock theta functions. Ono reflects on how Ramanujan has been a source of not just mathematical but also personal inspiration throughout his life. Today, Ono himself is an inspiration to many.

My Search reminds us of the finite nature of life. The reader encounters suicide attempts by Ramanujan and Ono, Ramanujan’s untimely death at age 32, the passing of Weil in 1998, Gordon in 2012, Sally in 2013, Aczel in 2015, and the overall shadow of death that war can cast on life. In the face of death and hardship, the book also offers elements of spirituality, positivity, and hope. Ramanujan’s spirituality is well-known. Some of his results and mathematical ideas, he said, were divined to him by his goddess Namagiri. Ono describes his own spirituality towards the end of the book, and offers advice, under the umbrella of “the idea of Ramanujan”. In many different ways, Ramanujan’s spirit and the Hardy-Ramanujan story persists and inspires throughout My Search, reaching many of the book’s characters including Ono, his father, Ono’s mentors Sally, Gordon, and Granville, and Weil. “Live mathematically, but not by the numbers”, says Ono, citing creativity, curiosity, flexibility, confidence, determination, and rigour as qualities we should all try to enhance in ourselves.

My Search is as much a story of humanity as it is mathematics. It is accessible to a wide audience, and has already gained a broad readership. The book’s mathematical content is minimal but not totally absent; an epilogue delves into some of the mathematics behind the scenes, but in a way that is accessible to those without a mathematical background. {My Search} speaks to mentors, students, mathematicians, enthusiasts, and anyone seeking inspiration regardless of their mathematical or academic interests, and also those who enjoy a refreshingly human story which in many ways transcends the passage of time.

Amanda Folsom is Associate Professor of Mathematics at Amherst College. Like Ken Ono, Folsom attended the University of Chicago as an undergraduate and UCLA for graduate school (both after Ono); Ono was her postdoctoral mentor from 2007–10 at the University of Wisconsin. Folsom and Ono have written seven research articles and one book together.