‘The Last Theorem’ by Arthur C. Clarke and Frederik Pohl

The most exciting part of “The Last Theorem” (Del Rey: 304 pp., $27), the novel by the late Arthur C. Clarke and fellow science fiction veteran Frederik Pohl, has nothing to do with the titular titillation of finding a proof for Fermat’s famous marginal musing, nor with a secret weapon called Silent Thunder that instantly renders all of North Korea a demilitarized zone, nor with the umpteenth invocation of Clarke’s famous “space elevator” concept, which substitutes traditional rocket launchers with a giant ladder to the heavens. (For these, you need look no further than Clarke’s other 2008 collaboration, “Firstborn,” with Stephen Baxter.) Rather, “The Last Theorem” involves a part of the Clarke legend that has long been acknowledged but rarely discussed.

By the time of his death in March, the 90-year-old Clarke had presented readers with myriad visions of the future, at once awesome and sobering, in books like “Childhood’s End” and the germ and eventual novelization of “2001: A Space Odyssey.” Mankind regularly gets a reality check upon contact with vastly superior races, finding itself instantly demoted from center-of-the-universe status to a mere means to an inscrutable end. In the grand scheme of things, the interior life of his characters is insignificant.

Not surprisingly, his private life was excluded from the universe of his books. Though it seems an open secret among many that he was homosexual, Clarke was coy regarding his sexual orientation. (Asked if he was gay, he would respond, “No, merely mildly cheerful.”) Any link between his books and this facet of his life remains obscured.

Thus the reader is caught off guard by “The Last Theorem.” In this first posthumously published work, Clarke delivers a bombshell in the first chapter. “The Last Theorem’s” ostensible protagonist is Ranjit Subramanian, a smart, “good-looking” Sri Lankan whom we meet at age 16. (Clarke lived in Sri Lanka for more than 50 years and died there.) Already the temperature of the prose is several degrees warmer than in a typical Clarke novel: “[H]is skin color was the rich dark brown of a spoonful of cocoa powder, just before it went into the hot milk.”

Ranjit and his best friend have become lovers over the first few pages. Soon enough, Ranjit awaits a lecture from his father: “It could have been avoided entirely if he had only remembered to lock his bedroom door so that the porter at his university lodgings would not have been able to blunder in on the two of them that afternoon.”

When his father broaches the subject of the love that hasn’t managed to speak its name, the objection turns out to be on different grounds than Ranjit feared: “You must believe me in this, Ranjit. It isn’t the experimenting with sexual behavior that matters. It is the person you were sharing it with. . . . Remember, my son, you are a Tamil. [Gamini] is Sinhalese.” Gamini is soon shipped to London for schooling, and his letters to Ranjit are at once chipper and restrained. (Clarke and Pohl wring humor from Gamini’s constant cryptic references to a personage named “Madge,” which make Ranjit suspect he’s being thrown over for a woman.)

The evocation of Ranjit’s sex life is far from steamy, but it simultaneously grounds and complicates a story that seems to be stretching out in all directions; the fact that Ranjit and Gamini’s relationship is depicted so early in the book suggests that a connection between the writer’s sexuality and the starry regions of science fiction might at last be elucidated. The connection is also hinted at during a seemingly autobiographical preamble, in which Clarke, as a pilot officer in the RAF in 1943 and “already a keen space cadet,” has the chance to play with a powerful new radar device: “[O]ne night he aimed it at the rising moon and counted for three seconds to see if there would be a return echo.” Nothing happens, at the time; but the novel playfully suggests that the beam might have drawn the attention of supremely powerful beings way beyond our ken.

Clarke and Pohl concoct an array of almighty aliens, whose descriptions punctuate the book’s early, otherwise earthbound chapters. Unexpectedly, the authors hit on the tone of comi-cosmic discrepancy found in Douglas Adams’ “The Hitchhiker’s Guide to the Galaxy” or Kurt Vonnegut’s “The Sirens of Titan.”

The first third of “The Last Theorem” is a blast, with multiple lines of inquiry spiraling around one another. But there’s no payoff, and the last 200 pages feature a hodgepodge of inconsequential, even random-seeming set pieces and an unsatisfying telescoping of the time frame. Ranjit effortlessly slips into a wholly satisfying marriage with a beautiful woman, an A.I. expert. The book’s winning and winking self-consciousness evaporates (save for a mention of Sri Lanka’s one “world-famous celebrity,” a writer who “hardly ever comes out of his house”).

Despite its title, “The Last Theorem” engages only fitfully with mathematics, offering a few nifty parlor tricks but never really connecting Fermat’s theorem (and Ranjit’s scantly described solution) to the impending alien hordes or even to the prime-number cryptography that the authors briefly mention. One wonders how stable the manuscript was when Clarke died. The book ends with some characters achieving a kind of immortality, but “The Last Theorem” does nothing to burnish the legacy of either of its authors.

Ed Park is a founding editor of “The Believer” and the author of the novel “Personal Days.” Astral Weeks appears monthly at www.latimes.com/books.