Computing with Quantum Cats (7 page)

Among Turing's many “firsts,” he now became the first person to program a computer to play musical notes by adjusting the speed of “beeps” sent to a loudspeaker. Learning of this, Christopher Strachey (a nephew of Lytton Strachey), who had been a pre-war contemporary of Turing at King's and had written a program to play draughts (checkers) on NPL's ACE machine, came to Manchester and wrote programs that could play “God Save the King,” “In the Mood” and “Baa Baa Black Sheep.” In 1951, the results were broadcast by the BBC—on
Children's Hour
.
²⁰
Turing also wrote his letters on the Manchester computer's keyboard, thereby probably becoming the first person to use a word processor.
²¹

Turing's principal contribution was typically Turing, and the antithesis of what he called “the American tradition”: a very efficient programming system that was easy for Turing to work with, using binary code, but almost impossible for anyone with a lesser intellect to get to grips with. It was Tony Brooker, who joined the team in October 1951, who worked out how to write programs in a language that looked like algebraic expressions, which were translated automatically into the code the machine understood. This was the first publicly available “high-level” computer language, the forerunner of things like Fortran and Algol.

By the time Brooker came on the scene, Turing, recently elected a Fellow of the Royal Society, had essentially moved on from artificial computing systems, and was deeply immersed in the puzzle of morphogenesis, the biology of how organisms grow and develop. While DEUCE, EDSAC, the Manchester team and other British projects (one developing
from secret work for the Admiralty, another at Birkbeck College in London) developed towards the kind of computers we know today, Turing was again ahead of the pack, puzzling over the way living things are controlled by their “programming.” His paper “The Chemical Basis of Morphogenesis,” published in 1952, is regarded as being as important in this field as “On Computable Numbers” is in its own.

But by then time was running out for Turing. Early in 1952 he had a brief homosexual relationship with a nineteen-year-old boy who was then involved in a burglary of Turing's house in Manchester. Turing reported the burglary to the police, naively expecting them to help him; when they found out about the relationship they arrested Turing,
²²
who was charged and convicted of the offence that “being a male person [he had] committed an act of gross indecency with…a male person.” His burglarious “friend” was convicted of the same offence, but seen as Turing's victim and discharged. Turing was put on probation, on condition he took a course of hormone treatment. The court probably thought it was being lenient, but the “treatment,” with the female hormone estrogen, made him impotent and fat, and, worst of all, affected his ability to think clearly and concentrate.

These events are often linked to his untimely death in 1954, officially determined to be suicide. The situation is in fact rather more complicated than the coroner's verdict suggests. At the time of his death the hormone treatment had been over for a year, and friends describe him as being happy. Work was going well. He had left a “to do” list for himself at work before going home for the weekend, and rather than a suicide note he left behind ready to post a letter accepting an invitation to a forthcoming event at the Royal Society.
Nothing suggests a suicidal frame of mind. So why the verdict? Well, he did die of cyanide poisoning, and there was a partly eaten apple by his bedside, recalling the couplet from
Snow White
:

Dip the apple in the brew,

Let the Sleeping Death seep through.

Bizarrely, though, the apple was never tested to see if it contained cyanide, and Turing had a home laboratory (little more than a glorified cupboard) where, just as in his childhood, he dabbled with chemistry experiments. Some of these involved electroplating using potassium cyanide solution, and police called to the scene reported a strong smell of cyanide (the famous “bitter almonds” smell) in the room. A jam jar containing cyanide solution was standing, uncovered, on the table in Turing's “lab.” Perhaps significantly, the ability to smell cyanide diminishes over time, as the concentration of the gas increases, and the post-mortem examination showed that Turing's liver had a low concentration of the poison, not consistent with its having been swallowed.

The simplest explanation is that Turing accidentally inhaled a lethal dose of cyanide just before going to bed. At the other extreme, conspiracy theorists have suggested that as a homosexual who knew too many secrets he was murdered on “official” orders. Somewhere in between there is the coroner's verdict of suicide. But it is useless to speculate. What matters is that on the night of June 7, 1954, at the age of just forty-one, Alan Turing, the founder of modern computing, died as a result of ingesting cyanide.

The American approach to electronic computing, which Turing derided, was championed by John von Neumann (usually known as “Johnny”) who, as it happens, was actually born in Hungary as Neumann János Lajos (in Hungarian the family name comes first) or “Jancsi” to his family.

JANCSI

He was born in Budapest on December 28, 1903, the eldest son of a prosperous Jewish banker. His father had benefited from the general economic prosperity of Hungary following the turmoil of the 1860s which had led to the creation of the Austro-Hungarian dual monarchy out of the old Austrian Empire, and specifically from the easing of anti-Jewish restrictions and attitudes in the final decades of the nineteenth century. Originally Neumann Miksa (Max Neumann), in 1913 Jancsi's father acquired a hereditary title, ostensibly “for meritorious service in the financial field,” although it
helped that he also made a substantial contribution to the state coffers.
¹
As a result, he became Margittai Neumann Miksa—in German, Maximilian Neumann von Margitta, Margitta being the ancestral home of the Neumann family and also a play on the name of Max's wife, Margit. So Jancsi became Margittai Neumann János, in German Johann Neumann von Margitta, later simplified to Johann von Neumann, and in English, later still, Johnny von Neumann. As if that were not confusing enough, his two younger brothers, who like Johnny emigrated to the United States, each adopted a different version of the surname. Michael (originally Mihály) simply dropped the “von” and became Michael Neumann, while Nicholas (originally Miklós) added it to the surname to become Nicholas Vonneumann.

But all that lay far in the future when Jancsi, growing up in Budapest, was first showing signs of his unusual mental ability. He could recall, verbatim, the contents of any book that he read, and devoured the contents of his father's library. Initially the children were educated at home, benefiting from the attentions of both French and German governesses, with specialist tutors in other subjects. During the First World War, they learned English from two British men who had been interned as enemy aliens but were under the protection of Max von Neumann. The family was scarcely touched by the war or its aftermath, including the short-lived but bloody communist regime of 1919. At that time, housing was “reallocated,” ostensibly on the basis of equal shares for all, and a Communist Party official came to assess the needs of the von Neumann family, who had a very large apartment. Nicholas Vonneumann recalled that his father left a bundle of British pound notes on the piano while the assessment was
being carried out. After the assessment, the money had gone and the family retained the apartment.
²
When things grew uncomfortable in Budapest, they simply went away to their summer home near Venice for a few weeks. Even so, the experience left Johnny von Neumann, who turned sixteen at the end of 1919, with a lifetime loathing of communism in all its forms.

Jancsi's high school education had begun almost at the same time as the war, in 1914, when he was ten. He attended the Lutheran Gymnasium in Budapest, an elite school famous for its mathematical teaching, where his talent was quickly appreciated and nurtured.
³
By the age of thirteen, he was being fast-tracked not just by the teachers at the school—advanced mathematicians who carried out research alongside their teaching—but also by Joseph Kürschák, a professor at the University of Budapest. At seventeen he published an original paper (co-authored with one of his teachers), and on leaving school that year, 1921, he wanted to become a mathematician. Max von Neumann was horrified, pointing out that there was no money to be made in mathematics. But father and son agreed a compromise—the kind of compromise which made perfect sense to Johnny. He enrolled to study a “sensible” subject (chemical engineering) at the University of Berlin, later transferring to the Eidgenössische Technische Hochschule (ETH: the Swiss Technical High School) in Zürich, and simultaneously as a mathematics student at the University of Budapest, where he was already well known. Over the four years up to 1925 he duly attended lectures in Berlin and Zürich, and, by arrangement with his professor, popped in to the University of Budapest at the end of each term solely to take examinations. He also prepared a
thesis, on set theory, to be offered to the University of Budapest for a doctorate. His final examinations at both institutions were taken in 1925 (he passed, of course, with the highest possible grades) and his doctorate was awarded in 1926. No more was heard of chemical engineering as a career, and von Neumann started his career in mathematics as a
Privatdozent
(the most junior kind of lecturer) at the University of Berlin the same year, while working for a qualification known as the
Habilitation
, a kind of higher doctorate required in the German system before becoming a professor.

One of von Neumann's examiners for his doctorate was the great David Hilbert, the most influential mathematician of his generation (he had been born in 1862), whose work would, as we have seen, soon be the inspiration for Turing's investigations into (in)computable problems. Hilbert was based at the University of Göttingen, and alongside his post in Berlin von Neumann was awarded a Rockefeller Fellowship, which enabled him to carry out research in Göttingen with Hilbert during the academic year 1926/7. Between 1926 and 1929 he published twenty-five scientific papers and established a reputation as a quantum theorist—his book
Mathematical Foundations of Quantum Mechanics
, which was published in 1932, was highly influential, coming to be regarded as a standard text—although, as we shall see, it contained one major flaw. Still in his twenties, he was a glittering star in the mathematical firmament, and his fame had spread worldwide. He had scarcely moved on from Berlin to a more senior post in Hamburg when in 1929 he was invited to visit Princeton to lecture on quantum theory. Replying that he had some personal matters to attend to first,
von Neumann made a flying visit to Budapest to get married, to Marietta Kovesi, before becoming a visiting lecturer at Princeton University in February 1930.

Although von Neumann was actually a rather poor lecturer—he had a habit of writing complicated equations in a small corner of the blackboard and erasing them before the students could copy them down—the visit led to his appointment as a professor at Princeton the following year. He loved America, America seemed to love him, and although at first he still held scientific posts in Germany and visited there in the summers, the developing political situation made this a less and less attractive arrangement. Things came to a head in 1933. In January, von Neumann was offered the opportunity to become one of the founding professors at the new Institute for Advanced Study at Princeton (with a starting salary of $10,000), and a few days later Adolf Hitler was appointed Chancellor of Germany. Within months, the new regime began a purge of Jewish academics, and von Neumann eventually resigned from his German positions, although he continued to visit Europe throughout the 1930s.

JOHNNY AND THE INSTITUTE

The Institute for Advanced Study was founded in 1930, with funding from the philanthropist brother and sister Louis Bamberger and Caroline Bamberger Fuld. They had originally intended to endow a medical school, but after being advised that there were already plenty of medical schools in the United States were persuaded to commit $5 million to set up a research institution where scholars would be free of any diversions such as teaching, and, with life tenure, any worries about the future. Mathematics was the obvious faculty to start
the venture with, since at that time mathematicians famously needed nothing more than pencil and paper to work with. The Institute operated on the basis of two terms, running from October to April either side of an extended Christmas break, and required of its academics only that they be in residence during termtime, which amounted to about half the year.

The basis for such an idyllic institution has been questioned, most notably by Richard Feynman, who wrote in his book
Surely You're Joking, Mr. Feynman?
:

When I was at Princeton in the 1940s I could see what happened to those great minds at the Institute for Advanced Study, who had been specially selected for their tremendous brains and were now given this opportunity to sit in this lovely house by the woods there, with no classes to teach, with no obligations whatsoever. These poor bastards could now sit and think clearly all by themselves, OK? So they don't get any ideas for a while: They have every opportunity to do something, and they're not getting any ideas. I believe that in a situation like this a kind of guilt or depression worms inside of you, and you begin to worry about not getting any ideas. And nothing happens. Still no ideas come. Nothing happens because there's not enough real activity and challenge: You're not in contact with the experimental guys. You don't have to think how to answer questions from the students. Nothing!

But the timing was perfect, as Jewish and other scholars fleeing Nazi persecution began to look for safe havens, and the success of the Institute was assured when Albert Einstein, the most famous of these scientific refugees, was persuaded to make Princeton, rather than Caltech, his base.

Von Neumann, of course, was not a political refugee, but had already chosen to make his career in the United States. Like Einstein, he was a founding member of the IAS's School of Mathematics, which opened in 1933 and was quickly followed by Humanities in 1934 and Economics and Politics in 1935. Johnny stood out from the crowd in many ways. Always smartly dressed (often described as looking “like a banker”), he had a predilection for large cars, buying a new Cadillac every year, though he was a terrible driver and often got speeding tickets. He loved to hold lavish parties, and according to his daughter, Marina, he needed only three or four hours' sleep a night.
⁴
Marina was born in 1935, but by the time she was two her parents were divorcing, although they remained on friendly terms and she saw both of them. Johnny had met another Hungarian, Klára (Klári) Dán, on his visits to Europe, and decided they were soul mates. Klári was (by her own admission) a spoiled little rich kid, born in 1911 and by 1937 nearing the end of her second marriage. The situation was complicated not just by the developing political storm (in Europe in 1938 to visit Niels Bohr's institute in Copenhagen, Johnny was struck by the fact that the trains through Germany were full of soldiers) but by the need for getting two divorces, in different countries, and fulfilling the requirements to get Klári an immigration visa for the United States. Johnny had become a US citizen in 1937, but initially retained his Hungarian citizenship as well; unfortunately, Hungarian law (to which he was subject as a Hungarian citizen) did not recognize his American divorce. So he had to renounce his Hungarian citizenship and marry as an American citizen, which in turn enabled Klári to obtain the necessary visa as his wife. The formalities took months, and it
was November 18, 1938, before the couple were finally married in Budapest. The following month they sailed for New York from Southampton on the
Queen Mary
, arriving a week before Christmas. The marriage lasted for the rest of Johnny's life, although it did not always run smoothly, and many personal insights into his character come from a memoir Klári wrote, now in the possession of Johnny's daughter Marina. One intriguing tidbit is that Johnny, like so many gifted mathematicians, suffered from a mild compulsive disorder, one manifestation of which was that whenever he turned a light on or off he had to do so by flipping the switch exactly seven times.

The couple were childless. Klári suffered a miscarriage in the summer of 1942, and with Johnny often away on secret war work, in 1943 she took a job with the Office of Population Research at Princeton University. The training she gained there in statistical work would prove invaluable when she later worked with Johnny as one of the first computer programmers—but that is getting ahead of our story.

In spite of the distractions of his personal life, and the parties (which continued with Klári as hostess), Johnny was one of the early stars of the Institute, proof that Feynman's reservations did not apply to everyone there. Between 1933 and the end of 1941, when America was forced into war, he published thirty-six scientific papers and, even more significantly, met Alan Turing and learned about his work. But long before the Japanese attack on Pearl Harbor, Johnny was becoming involved with the military. He became a US citizen on January 8, 1937, and was so concerned about the situation in Europe that he soon applied for a commission in
the reserve of the US Army, being turned down solely on grounds of age (he had just passed the cut-off age of 35 by the time he had completed the required examinations). Instead, he became a consultant to the US Army's Ordnance Department, and then (in 1940) a member of the scientific advisory board for its Ballistic Research Laboratory. Other appointments followed, including membership of the National Defense Research Council (NDRC) and work for the US Navy (which, among other things, took him on an extended visit to Britain). By the time the Japanese bombs fell on Pearl Harbor on December 7, 1941, he was the go-to man for advice about large explosions, had a reputation for being able to break down complex problems into their simple components, and was a skillful chairman of committees who got things done. Inevitably—although he kept fingers in many pies—he was drawn towards the Manhattan Project.