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Dev Patel stars as in The Man Who Knew Infinity.

FILM In search of Ramanujan Andrew Robinson marvels afresh at the self-taught mathematical genius in a new biopic.

he story of the Indian mathematician imagination to invent The Man Who personal intimacy; Hardy, for instance, had Srinivasa Ramanujan (1887–1920) them.” Hardy lured Knew Infinity only a faint idea of Ramanujan’s growing is improbable. Self-taught, he made Ramanujan to Cam- WRITTEN AND depression, which led to a suicide attempt on Tmany seminal discoveries in bridge, even though DIRECTED BY the London Underground. Irons, however MATTHEW BROWN and power series — most famously concern- foreign travel was Edward R. Pressman brilliant, is a generation older than Hardy ing the partition of numbers into a sum of considered an offence Films/Animus Films: was in 1914, and Patel is taller and nattier smaller integers — that continue to fascinate against Hindu caste 2016. than the more corpulent Ramanujan, who mathematicians and intrigue physicists study- purity. They collabo- was ill at ease in Western dress. ing black holes and quantum gravity. In The rated intensively throughout the First World Much of the action — and Man Who Knew Infinity, director Matthew War. Ramanujan had no university degree, — takes place in the handsome precincts of Brown dramatizes the purest of mathemat- but in 1918, Hardy ensured that he was Trinity College, which opened its doors to ics for a general audience, and explores the elected a fellow of the Royal Society — the a feature film for the first time. In Hardy’s strange personal life of Ramanujan, who first Indian to receive the honour after it was room and the quadrangles, Ramanujan per- died at 32, at the height of his powers, prob- restricted to scientists — and of Trinity Col- sistently resists Hardy’s demands for proofs ably from tuberculosis. Based on the compel- lege. They encountered considerable opposi- of his tantalizing theorems. An excited ling biography of the same name by Robert tion, some of it racially motivated. Ramanujan infuriates a lecturer by failing to Kanigel (Scribner, 1991), the film took more Hardy’s relationship with Ramanujan take notes and then quickly chalking a correct than ten years to create. It is worth the wait. holds the film together. Convincing perfor- formula: a very special integral due to Carl Ramanujan’s career was ‘made’ by Brit- mances by Jeremy Irons as Hardy and Dev Friedrich Gauss, which Ramanujan knew ish mathematician G. H. Hardy, a fellow of Patel as Ramanujan were carefully refined through a method of his own devising. And Trinity College, Cambridge. In 1913, while by the film’s Japanese–American mathemat- in an evocative scene in working as an accounts clerk in what is now ics adviser, Ken Ono, whose academic career Trinity’s Wren Library, NATURE.COM Chennai, Ramanujan sent Hardy startling, has been dedicated to exploring Ramanujan’s the famously atheistic For more on science entirely unproven, theorems out of the blue. theorems. Irons and Patel animate both the Hardy tells his Indian in culture see: “They must be true,” wrote Hardy, “because, consuming passion for mathematics shared protégé that the great- nature.com/ if they were not true, no one would have the by the two, and their astonishing lack of est honour “is to have a booksandarts

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legacy at Wren once we are gone. In this very PSYCHOLOGY library are the Epistles of St Paul, the poems of Milton, Morgan’s Bible and, in my estimation as a man of numbers, the pièce de résistance, Newton’s Principia Mathematica.” Ramanu- Time piece jan’s ‘lost notebook’ — which contains impor- tant mathematical discoveries made in India Hedderik van Rijn weighs up an erudite but in 1919–20 and was neglected until 1976 — is, idiosyncratic survey of how we perceive life passing. fittingly, in the Wren Library. Scenes in India are no less ravishing. We see Ramanujan in flowing Indian clothes he sense of time passing plays a techniques such as with Brahminical caste marks, chalking end- pivotal part in decision-making — a focus on breath- less equations on the floors of a highly deco- from choosing chicken or pasta on ing, Wittmann rated Hindu temple. His dominating mother Ta long-haul flight to deciding whether to argues, we become Komalatammal and wife Janaki provide a propose marriage to a long-term partner. more aware of our glimpse of domestic life. Indian and British Although the temporal resolution in these inner body states, colonial figures come and go (with a cameo scenarios differs by orders of magnitude, more “mentally by Ramanujan admirer Stephen Fry). But the Felt Time by psychologist Marc Wittmann present”; this slows film struggles to shed light on the origins of (first published in German as Gefühlte Zeit; down our subjec- Ramanujan’s prodigious gift. Biographers C. H. Beck, 2014) argues that the experi- Felt Time: The tive time, resulting have had the same problem with Gauss and ences are closely related. Psychology of How in more fulfilling many other mathematicians. As India’s great Wittmann marshals a wealth of behav- We Perceive Time in-the-moment film director Satyajit Ray put it: “This whole ioural and neuroscience results, as well as MARC WITTMANN experiences. (TRANSLATED BY ERIK business of creation, of the ideas that come references to the arts, literature and philo­ BUTLER) I am not con- in a flash, cannot be explained by science.” sophy, to argue that how we subjectively MIT Press: 2016. vinced that mind- Hardy, too, was dazzled and puzzled. On a experience time determines whether we fulness can help 0–100 scale of natural mathematical ability, are able to seize the day and live happy in all contexts dis- he gave himself a score of 25 and Trinity col- and fulfilled lives, or struggle to finish cussed in Felt Time, because Wittmann league John Littlewood (a fellow supporter of our daily chores. He urges us to strive to defines time very loosely. He links the Ramanujan) 30, compared with 80 for influ- slow down subjective time and to live in perception of seconds with percep- ential mathematician David Hilbert and the here and now. Inspired by the Roman tion over months or years. He elides the 100 for Ramanujan. “The limitations of his Stoic philosopher Seneca, his suggestion effects of circadian rhythm and chrono- knowledge were as startling as its profundity,” for cultivating presence is to abstain from type (whether someone is a ‘morning’ or Hardy wrote after Ramanujan’s death. “All his busywork — to get rid of the “uncondi- ‘evening’ person), youthful impatience, results, new or old, right or wrong, had been tional work ethic” that drives us back to the observation that years seem to pass arrived at by a process of mingled argument, our desks on sunny Sunday afternoons to faster as we age, and the prospect of dying intuition and induction, of which he was finish yet another grant proposal instead — the ultimate time limit. Although all of entirely unable to give any coherent account.” of relaxing. Another, more pragmatic, these are associated with our perception of Ramanujan has inspired many. proposal for slowing down subjective life passing, each has a distinct aetiology: Christopher Sykes’s pioneering UK televi- time is ‘mindfulness’. By using meditation circadian rhythms are driven by well- sion documentary, Letters from an Indian known biological circuits, for example. Clerk, was screened in 1987. The play A Dis- But the change in subjective time with age appearing Number, devised by Théâtre de is attributed to experiencing fewer unfa- Complicité, was produced in Britain in 2007 miliar (and therefore memorable) events, (see Nature 449, 25–26; 2007). A biographi- something that could be more easily influ- cal novel by David Leavitt, The Indian Clerk enced than circadian rhythms. (Bloomsbury), was published in 2007. I do, however, strongly agree with Now, the film has spawned an intriguing, Wittmann’s implicit arguments for a moving autobiography by Ono, My Search more inclusive study of time. Beyond for Ramanujan (Springer, 2016), written with simple laboratory studies of temporal

SIMON DAWSON/BLOOMBERG VIA GETTY SIMON DAWSON/BLOOMBERG science writer , who died before cognition tasks, Wittmann makes the publication. Ono interweaves Ramanujan’s case that science should explore how life and work with his own fight to become a perceived time affects everyday activi- mathematician — including a suicide attempt ties, as well as how everyday activities — in the shadow of his distinguished math- influence our perception of time. But ematician father, Takashi Ono. After years of rather than conducting lab work in which estrangement, the Onos realized that they participants must estimate the duration were united by admiration and affection for of intervals marked with clear start and the university drop-out Ramanujan. Here is end points, we should consider timing yet another example of how this enigmatic as a continuative process: every task we Indian’s unique achievements continue to do is timed, irrespective of whether we reverberate nearly a century after his death. ■ know at the start that time might become important. Andrew Robinson is the author of Genius Felt Time is divided into two parts. In the and Satyajit Ray: The Inner Eye. Perceived and measured time may not first, Wittmann introduces the important e-mail: [email protected] always match. role of time in many aspects of everyday

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