Turing's Cathedral Read online

  Von Neumann found himself back among the punched cards he remembered from when his father brought parts of a Jacquard loom–control system home from work. “In March or April 1944,” says Metropolis, “von Neumann spent two weeks working in the punched-card-machine operation, pushing cards through the various machines, learning how to wire plugboards and design card layouts, and becoming thoroughly familiar with the machine operations.”66

  There were fewer than two years from the first, tentative theoretical models to the successful test, code-named Trinity, of an implosion weapon at the northern extremity of the Alamogordo Bombing Range on July 16, 1945. Despite the pressure to complete the job, the physicists found time to relax. “We used to go for walks on Sunday,” remembers Feynman. “We’d walk in the canyons, and we’d often walk with Bethe, and Von Neumann, and Bacher. It was a great pleasure. And Von Neumann gave me an interesting idea; that you don’t have to be responsible for the world that you’re in. So I have developed a very powerful sense of social irresponsibility as a result of Von Neumann’s advice. It’s made me a very happy man ever since.”67

  With von Neumann, the veil was rarely lifted. “One time, in early 1945, he came back from Los Alamos and proceeded to behave in the most unusual ‘Johnnyesque’ manner,” Klári recounts. “He arrived home sometime mid-morning, immediately went to bed and slept twelve hours. Nothing he could have done would have had me more worried than Johnny skipping two meals, not to speak of the fact that I had never known him to sleep that long in one stretch. Sometime late that night he woke up and started talking at a speed which, even for him, was extraordinarily fast.”

  “What we are creating now is a monster whose influence is going to change history, provided there is any history left,” he said, in Klári’s account, “yet it would be impossible not to see it through, not only for the military reasons, but it would also be unethical from the point of view of the scientists not to do what they know is feasible, no matter what terrible consequences it may have. And this is only the beginning!”

  The concerns von Neumann voiced that night were less about nuclear weapons, and more about the growing powers of machines. “While speculating about the details of future technical possibilities,” Klári continues, “he gradually got himself into such a dither that I finally suggested a couple of sleeping pills and a very strong drink to bring him back to the present and make him relax a little about his own predictions of inevitable doom.”

  “From here on, Johnny’s fascination and preoccupation with the shape of things to come never ceased,” concludes Klári’s account. For the next seven years he neglected mathematics and devoted himself to the advance of technology in all forms. “It was almost as if he knew that there was not very much time left.”68

  We have only hints of von Neumann’s final thoughts. “As he came more and more to realize that the control over the physical forces of nature which he and his co-workers had placed in the hands of their fellow men could be used for evil as well as for good, he felt with steadily increasing intensity the moral problems bound up with the greatest of modern scientific triumphs,” said Father Anselm Strittmatter, the Benedictine monk who spent many hours at von Neumann’s bedside during his final months and delivered the last rites at his death. “As for his own role in this complex situation, in spite of the dismal possibilities he envisioned, he knew no hesitation, he had no regrets.”69

  “There is a unifying force behind all manifestations of nature, which we cannot fully comprehend, but we can try to explain it with the means at our disposal,” says Nicholas Vonneumann, summing up his brother’s life. “It was in this spirit that John tried to comprehend … the mysteries of atomic and subatomic particles through quantum mechanics, the mysteries of weather … through hydrodynamics and statistics, the mysteries of the central nervous system through … artificial computers, the mysteries of genetics and inheritance through his theory of self-reproducing automata.”70

  Even Klári, closer to von Neumann than anyone else, was never fully able to understand this “strange, contradictory, and controversial person; childish and good-humored, sophisticated and savage, brilliantly clever yet with very limited, almost primitive lack of ability to handle his emotions—an enigma of nature that will have to remain unsolved.”71

  “No matter which way you looked he always seemed to belong somewhere else,” explains Klári. “The pure mathematicians claimed that he had become a theoretical physicist; the theoretical physicists looked at him as a great help and advisor in applied mathematics; the applied mathematician was awed that such a pure and ivory-towerish mathematician would show so much interest in his applied problems and, I suspect, in certain government circles they may have thought of him as an experimental physicist, or even an engineer.”72

  On August 6, 1945, a uranium-fueled atomic bomb yielding 13 kilotons was dropped on Hiroshima, followed by a plutonium-fueled bomb yielding 20 kilotons on Nagasaki on August 9. The Japanese surrendered on August 15. “Isn’t it wonderful that the war is over?” Marina wrote to Klári on August 28. “Is Daddy still going to travel so much now the war is over? I hope not.”73 Von Neumann’s travels—between Princeton, Aberdeen, Los Alamos, Santa Monica, Chicago, Oak Ridge, and Washington, D.C.—continued.

  World War II was over, but the cold war had begun.

  FIVE

  MANIAC

  Let the whole outside world consist of a long paper tape.

  —John von Neumann, 1948

  ON MONDAY, November 12, 1945, at 12:45 p.m., six people, led by John von Neumann, gathered in Vladimir Zworykin’s office at RCA’s research laboratories in Princeton, New Jersey. Vladimir Kosma Zworykin was a pioneer of television (and the last entry in many encyclopedias) who would live to regret that his invention’s capacity for transmission of intelligence had become a channel for so much noise. Captain Herman Goldstine (on loan from U.S. Army Ordnance and the Aberdeen Proving Ground) was one of the principal organizers of the army’s Electronic Numerical Integrator and Computer, or ENIAC, whose existence would not be made public until February 1946. Statistician John Tukey (of Princeton University and Bell Laboratories) provided a direct link to Claude Shannon, whose mathematical theory of communication showed how a computer built from unreliable components could be made to function reliably from one cycle to the next. Jan Rajchman and Arthur Vance were engineers, and George Brown a statistician, from RCA. This first meeting of the Institute for Advanced Study’s Electronic Computer Project established principles that would guide the destiny of computing for the next sixty years.

  “The heart of the system is a central clock, carrying an enormous load,” the minutes report. The circuitry would be modular, because “this sort of design is favorable for mass production,” explained the engineers. “ ‘Words’ coding the orders are handled in the memory just like numbers,” explained von Neumann, breaking the distinction between numbers that mean things and numbers that do things. Software was born. Numerical codes would be granted full control—including the power to modify themselves.1

  The age of electronics began in 1906 with Lee De Forest’s invention of the vacuum tube, or, as the British (led by John Ambrose Fleming, whose work preceded De Forest’s) described it, the thermionic valve. Within an evacuated glass envelope, a charged cathode was heated to a temperature high enough to boil off electrons, whose flow to the anode (or plate) could be controlled by a secondary current applied to a very thin filament (or filaments) known as the grid. Switching (and signal amplification) was now possible at radio frequencies, rather than the speed of relays and Morse code.

  Zworykin, the youngest of seven children, was born in 1889 to a family of steamship owners on the Oka River in Russia. He was seventeen years old and a student at the Petrograd (St. Petersburg) Institute of Technology when he was discovered using the instruments in the physics laboratory for unauthorized experiments going beyond the problems that were assigned in class. Professor Boris Rosing took Zworykin aside and, instead of reprim
anding him, offered him a position in his own private lab. Rosing was producing his own electron tubes, which at that time required building his own vacuum pumps and formulating his own glass. He introduced Zworykin not only to the behavior of electrons within the evacuated glass envelope, but also to how these captive electrons could be coaxed into communication with the world of light outside.

  “I found that he was working on the problem of television about which I had never heard before,” remembered Zworykin sixty years later. “This was my first introduction to the problem which eventually occupied most of my life.” By the time Zworykin graduated with a degree in electrical engineering in 1912, “Rosing had a workable system consisting of rotating mirrors and a photocell on the pickup end, and a cathode ray tube with partial vacuum which reproduced very crude images over the wire across the bench.”2 Much of Zworykin’s subsequent career would be devoted to inventing better ways to translate, in both directions, between photons and electrons—commercial television being the way to make this pay.

  Rosing secured an appointment for Zworykin to work on X-ray diffraction with Paul Langevin in Paris, until interrupted by the outbreak of World War I. Returning to Russia, Zworykin was inducted into the army and rose to become an officer in the Signal Corps, where his knowledge of radio and ability to fix machinery, from generators to machine guns, enabled him to move freely through the ranks and escape execution by a succession of captors as the war drew to a close. During the Bolshevik Revolution and counterrevolution, wireless was the only way to determine, in the more remote parts of Russia, who was in power at any given time. Zworykin eventually escaped down the River Ob, through country whose residents, lacking telecommunication, were unaware there had even been a revolution, to the Russian Arctic, and then, with stops at Novaya Zemlya, Tromsø, Copenhagen, and London, he arrived in New York City on New Year’s Eve 1919.

  Zworykin presented himself to Boris Bachmeteff, the Russian ambassador in Washington, and secured a job as an adding machine operator at the Russian Purchasing Commission in New York. His wife, Tatiana, whom he had left behind in Russia, soon followed him to the United States. In 1920, after the birth of their first child, Zworykin joined a small group of fellow Russian émigrés at the Westinghouse laboratories in East Pittsburgh, where he was able to return to work on television in his spare time. He faced a series of obstacles, including the implosion of a prototype picture tube that slid off the back seat of his car as he stopped for a red light. The noise, mistaken for a gunshot, attracted the attention of a police officer, who grew suspicious at Zworykin’s attempted explanation, in broken English, of how pictures could be transmitted by radio waves to the device that lay shattered in the back of his car. “So you see pictures on the radio now? Sure … buddy!” the officer muttered, before taking Zworykin to jail until the facts were sorted out.3

  After failing to interest Westinghouse—then engaged in a bitter struggle against General Electric—in the commercialization of television, Zworykin transferred to RCA (successor to the American Marconi Company and progenitor of NBC), where David Sarnoff, a fellow Russian expatriate, placed the resources of RCA at his disposal. Sarnoff would end up sinking $50 million into the development of broadcast television—and fought a protracted patent-interference case against the American inventor Philo Farnsworth, who had independently developed an improved charge-storing camera tube that, in the opinion of the courts, predated Zworykin’s iconoscope, upon which the RCA television system, adopting Farnsworth’s improvements, was based.

  In 1941, Zworykin was appointed director of RCA’s new research laboratories in Princeton, situated adjacent to the Rockefeller Institute for Medical Research, two miles from the Institute for Advanced Study on the west side of the former Trenton–New Brunswick Turnpike, now Route 1. In addition to commercial television Zworykin helped bring the world the photomultiplier tube (for seeing in the dark) and the electron microscope (for seeing beyond the resolution of visible light). He devoted his later years to applying electronics to medical and biological research. “One cannot stumble on an idea unless one is running,” Zworykin advised those who joined his lab.4

  In October 1945, on the recommendation of von Neumann, Zworykin, who had been leasing a house next door to the Veblens, secured an exception to Institute housing policy that allowed him to purchase a home in the faculty enclave at the end of Battle Road, paying $30,000 in cash to paleographer Elias Lowe. Herbert Maass objected—not to Zworykin, but to the “rather substantial profit to Professor Lowe.”5

  Zworykin’s close relationship with Theodor von Kármán, who granted him access to secret military installations to work on electronic weapon systems, was viewed with suspicion by the FBI. Despite his anti-Soviet record, and contributions to the American defense effort that included night-vision gunsights and television-guided bombs, he was denied permission to travel to Moscow with a delegation of American technologists in 1945. J. Edgar Hoover personally labeled him a subversive, and his activities (including visits with his Philadelphia mistress) were monitored until 1975. In 1956 he refused to cooperate with an FBI interviewer, saying, “I left Russia to get away from state police.”6

  The development of electronics, according to Zworykin, could be divided into three epochs. “In the first, beginning with DeForest’s invention of the audion in 1906 and ending with the First World War, electron currents were controlled in vacuum tubes in much the same manner as a steam valve controls the flow of steam in a pipe,” he explained. “No more attention was paid to the behavior of the individual electrons in the tube than is customarily expended on the motion of the individual steam molecules in the valve.”

  “In the second period,” beginning in the 1920s, Zworykin continued, “the directed, rather than random, character of electron motion in vacuum was applied in the cathode-ray tube.” In the third period, beginning in the 1930s, beams of electrons were further subdivided into groups. “This subdivision was either on the basis of time, the electrons being bunched at certain phases of an applied high-frequency field as in the klystron or magnetron, or of space, as in image-forming devices,” Zworykin explained. “The electron microscope and the image tube are typical representatives of this group.”7

  During World War II, Zworykin and his protégé Jan Rajchman, an expatriate Pole educated in Zurich who had joined Zworykin’s group on New Year’s Day of 1936, sought to launch a fourth epoch in the evolution of vacuum tubes. In 1939, as Germany invaded Poland, Colonel Leslie Simon of the U.S. Army’s Ballistic Research Laboratory approached RCA about how to improve an antiaircraft gunner’s chances of shooting down enemy planes. To hit targets on the ground, a gunner could make use of firing tables prepared in advance. To place a shell in the path of a moving airplane required on-the-spot computation, including a last-minute estimate of time-of-flight to set a timed fuse so that the shell exploded as close as possible to the plane. “The Germans had a great dominance in the air and the Allies were very poor at antiaircraft fire control,” Rajchman explains. “Colonel Simon had the foresight to believe that electronics could provide the required speed.”8

  With Zworykin’s encouragement, Rajchman developed a series of digital processing and storage tubes: switching, gating, and storing pulses of electrons within single envelopes at megacycle speeds. The Computron and the Selectron, antediluvian ancestors of solid-state integrated circuits, were vacuum-tube versions of the microprocessor and memory chip. “The idea was to make a single tube which could multiply two numbers and add a third number to the product, the numbers being expressed in digital binary code,” Rajchman explains. “A number of electron beams emanating from a single central cathode were deflected each by three electrodes, corresponding respectively to a digit of the multiplier, a digit of the multiplicand, and a ‘carry-over’ digit.… In effect, the tube was made by ‘integrated vacuum technology,’ as we would describe it today.”9

  The Computron, invented by Rajchman and Richard L. Snyder, was a 64-pin, 14-bit arithmetical proces
sing tube containing 737 separate parts. No adjustments were possible once the envelope was sealed. “Numbers may be added or multiplied quickly and without the complication of timing impulses, clearing impulses or the like,” wrote Rajchman and Snyder in their patent application for a “Calculating Device” of July 30, 1943. By the time a proof-of-principle prototype was demonstrated, however, “it became clear that our pioneer work could not lead to an anti-aircraft director that could be used in actual combat soon enough.”10

  The Selectron was an all-digital, random-access, 4,096-bit electrostatic storage tube, built with vacuum-tube technology but functionally equivalent to modern silicon-based memory chips. “One should be able to go to any element without having to go to all the others [and] it should remember indefinitely without rejuvenation … just memorize forever until we want the information,” Rajchman explained in 1946.11 It was the prospect of the Selectron that convinced von Neumann that the path to digital computing lay through RCA. “John von Neumann came to see us frequently,” says Rajchman, “and became very familiar with our research.” Along with the Computron and the Selectron, Rajchman also developed the resistor-matrix function table, providing read-only memory, or ROM. “We made fairly large matrix arrays which had about a hundred and fifty thousand resistors in them,” he says. On October 30, 1943, he filed a patent for an all-digital “Electronic Computing Device” that would perform binary arithmetic at electronic speeds, using resistor matrices to store both invariant function tables as well as variable data to be operated upon. “The whole computation is made in the binary system of numeration so that any number is expressed as a sum of powers of two.”12 The proposed computer, both parallel and asynchronous, would have been exceptionally fast. It had no moving parts. The resistor matrices could be initialized with different functions and data as needed, tailored to different guns.