Elusive

PRELUDE

THE CASE OF THE DISAPPEARING PROFESSOR

In the weeks leading up to the day of the Nobel announcement in 2013, media excitement had grown intense in the expectation that this year the eighty-four-year-old scientist would win. The pressure on Peter Higgs had built over previous years, reporters even occasionally lurking uninvited outside the home of this intensely private man in Edinburgh’s New Town. For Higgs, the potential euphoria of winning the Nobel threatened to be overwhelmed by the demands of the media. Worse, if after all the anticipation the award were to go elsewhere, interest would only be magnified. Whatever the result was going to be, Peter Higgs had spent twelve months preparing.

Higgs’ apartment at the top of a three-storey Georgian tenement building is reached by a bare staircase of well-worn stone steps. As there are no lifts in the architecturally preserved townhouses of this UNESCO heritage site, Higgs has to climb eighty-four steps every time he returns home. In 2013, that meant one step for each year of his life. Such exercise has kept him fit into his ninth decade, well prepared for the sharp hills of Edinburgh’s spectacular volcanic scenery. On that October morning, he planned a stroll of about a mile to Princes Street where he would take a bus to Leith, on the shore of the Firth of Forth. He wanted to be well out of reach when the Nobel Prize was announced.

The view through the two sash windows in Higgs’ living room is historic and inspiring. Directly ahead stretch the cobbles of Darnaway Street, at the base of a canyon of sandstone townhouses which leads into Heriot Row and its pleasantly manicured gardens. Fifty metres away, on the left and opposite those gardens, is India Street, where at number 14 in 1831 was born the mathematician and architect of the theory of electromagnetism, James Clerk Maxwell. It was in Maxwell’s work that Higgs, back in 1964, had found the key to solving a fundamental problem in physics, and had first made himself a candidate for the Nobel Prize. Between the rooftops of Heriot Row and India Street are visible the River Forth and, on a clear day, the shores of Fife by Kirkcaldy, some thirty miles away.

We can imagine the bespectacled, rosy-faced professor, with his domed bald head and strands of white hair, as he stood at the edge of the window, unseen by any lurking journalist. The coast seemed clear. His disinformation plan—that he was away in the Scottish Highlands—appeared to have worked, so any photographers were seeking their quarry elsewhere. The owners of the ground-floor and first-floor flats had been careful not to allow anyone masquerading as a visitor to pass through the secure outer door from the street to the stairwell, but even so Higgs checked the landing outside his flat before starting down to the main entrance.

The basement of the property is below street level, separated from the pavement by a sunken passage. A small bridge, which crosses the well and links the front door to the street, is adorned with ornamental cast-iron railings and a lamp. Now powered by electricity, the light’s casing is the remnant of the gas lamp that illuminated the New Town in Georgian times. After a final glance to left and right he crossed the traverse, descended six steps to street level, and set off eastwards along Heriot Row.

It was a pleasant autumn morning, balmy for October in Scotland, with a gentle breeze from the south-west. Higgs was wearing a green-grey parka jacket, which would have been ideal camouflage had he indeed been in the Scottish Highlands, but still helped him merge anonymously in the streets of Edinburgh. His destination, Leith, was about three miles away. With collar pulled up around his neck, the acclaimed professor made his getaway. It would be another hour before his absence was noticed.

Sixteen months earlier, in June 2012, I had introduced Peter Higgs to the audience at a book festival in Melrose, near Edinburgh. Two hundred people filled a large marquee in the gardens of a mansion adjacent to Melrose’s ancient Abbey, at the height of summer. Peter Higgs was relaxed; it was his story, and he knew his lines. I was nervous. Although I have given talks about physics around the world for forty years, both to specialists and to the public, this was the first time I had taken the role of interlocutor to someone else’s tale.

And what a tale. Nearly half a century before, in the space of a few months, Higgs and five other theorists had independently discovered the key to how beauty and order emerged from the chaotic debris of the Big Bang. Their breakthrough underpins modern understanding of why the universe consists of shapes and forms, rather than of massless particles rushing through space at the speed of light, without any possibility of being caught in atoms or molecules. It also explains why the sun barely stays alight, the force converting its hydrogen fuel into helium and liberating energy being so feeble that the sun, instead of burning its fuel fast and expiring almost immediately, has survived billions of years.

All atomic particles belong to one of two families: fermions or bosons. The names honour two scientists, Enrico Fermi and Satyendra Bose, who in the early days of quantum mechanics studied how particles behave when in large groups. Fermions are the basic seeds of matter, such as electrons or quarks, which in quantum mechanics are like cuckoos: two in the same nest are forbidden. Bosons are like penguins: large numbers cooperate as a colony. Bosons can accumulate into the lowest possible energy state—an effect known as Bose-Einstein condensation, after the two scientists whose work explains this phenomenon. This extremely low-energy state is manifested in weird phenomena, such as the superfluid ability of liquid helium to flow through narrow openings without friction; in superconductivity; and, if the six theorists were correct, Higgs bosons condense to produce a weird substance—today known as the Higgs field—that fills the universe.

Two millennia after Aristotle argued that the realisation of “nothing” is untenable, the Higgs field is in effect a physical confirmation of that philosophy. According to Higgs’ theory, a truly empty vacuum devoid of all matter would be unstable. Add the Higgs field to this void, however, and it becomes stable. This may be counter-intuitive, but that is part of the theory’s magic.

Physics students are taught how in the nineteenth century attempts to find a ubiquitous ether, by sensitive measurements on the behaviour of light-waves as they bounced off mirrors and mingled together, found no evidence for this hypothetical stuff. Moreover, the absence of this ether was presented as a foundation of Albert Einstein’s celebrated special relativity theory on the nature of space and time. Yet in 1964 Higgs and those other theorists had found a loophole in the arguments that had dismissed the ether and, in effect, they resurrected it in the guise of what has become known as the Higgs field. At least, that was the theory; whether nature read their equations remained long unanswered.

At Melrose I began with a light-hearted provocation: “It is easier to be Shakespeare or Mendelssohn than a theoretical physicist.” Being in Scotland, I suggested that changing a few words in Macbeth, or a few notes in Mendelssohn’s Hebrides Overture, would still leave wonderful works of art; change a mere handful of symbols in Peter Higgs’ equations, however, and they would not work. Higgs’ theory was exciting conceptually, constructed from beautiful mathematical structures. Had this been a symphony or a work of literature, its value would have been recognised decades earlier. However, the ultimate value of a theory in physics is never decided by intrinsic elegance, let alone public opinion, but always by experimental test.

Of that sextet of theorists who had variously stumbled on the same idea—known by colleagues as the Gang of Six—Higgs alone had identified a means of testing the theory by direct experiment. To do so, he drew attention to an exceptionally ephemeral particle, now known as the Higgs boson, which the theory implies must exist. Find it, confirm that it behaves as the theory predicts, and you will have made a profound breakthrough in understanding nature.

On stage in Melrose, I explained that Higgs’ scribbled equations on a sheet of paper half a century ago had inspired CERN—the particle physics laboratory in Geneva—to build a vast machine capable of simulating the conditions of extreme heat that occurred in the aftermath of the Big Bang itself. Some of the smartest brains on the planet—more than ten thousand scientists, engineers, and technicians from around the world—had combined their expertise to collaborate in the quest.

The machine—an engineering marvel—is as large as can be fitted into the stable geology surrounding CERN, between Lake Geneva and the Jura Mountains. It was also at the limit of what could be afforded—about €10 billion. Even then, the combined efforts of many nations, and of the CERN management focusing its resources on this single enterprise for several years, were needed to bring the LHC to fruition. The purpose of all this in the public perception was to find Higgs’ boson. That was not wholly the case (as we shall see), but the amount of publicity which the gigantic venture excited had thrust him into the limelight.

If this huge weight of responsibility weighed on him, he did not show it. So, my first question at Melrose was this: “Peter, if tomorrow you found a mistake in your arithmetic, would you tell anybody?” It was a rhetorical question to help break the ice. There were no mistakes, of course. Over the decades many other mathematicians have checked and verified Higgs’ algebra, its basic ideas used like pieces of Lego to build other theories that have been tested experimentally. Hints of the boson’s existence had been seen and had given clues, like the footprints of some exotic creature in the snow might be used to puzzle out its identity. Forty-eight years previously, in 1964, no one could have foreseen the implications of the equations which Higgs had written on his sheet of paper in his office one July afternoon. One of his colleagues returned from summer vacation to find a note from Higgs on his desk: “This summer I had the only really original idea I’ve ever had.”1

¹

CHAPTER 1

A NAME ON THE BOARD

Peter Ware Higgs was born on 29 May 1929, in Newcastle upon Tyne. When Higgs first came to public notice in the 1980s, his Edinburgh professorship caused some media to describe him as Scottish, or even “Scotch”. He was in fact one-quarter Scottish. His parents came from Bristol, and his father’s family, who were descended from Saxon peasants, had lived in the west of England for generations.1

Peter’s grandfather, Albert Higgs, was in his late forties when he died suddenly, in 1911, after losing all his money. The cause of his death was probably suicide following ruin from gambling, but the truth remained a family secret. None of them would tell Peter the reason, and he clearly got the message: “Don’t ask!” Albert’s widow, Charlotte, now penniless and facing destitution, was left to care for Tom, their only child.

Charlotte and Tom joined forces with her widowed sister-in-law, Nelly, and her son, John, Tom’s cousin; the two families lived communally in the Redland area of Bristol. Charlotte contributed to the finances by working as a shop assistant, while Nelly looked after the boys’ welfare at home. Peter’s father, Tom, then age thirteen, was a high-flying classics scholar at Bristol Grammar School and was offered a bursary to cover his fees. With his interest in classics and influenced at home by Aunt Nelly, who was “disgustingly pious”, Tom expected to go into the church as a career. But World War I changed everything.2

In November 1916 Tom reached eighteen years of age and was conscripted. The first Battle of the Somme had been raging for four months. He was sent to fight in the trenches of northern France for what became two years of abomination and was “absolutely disgusted by the Church of England padres who exhorted the troops to go over the top and kill Germans”. As a child he had been fed Christian dogma, whose representatives in the trenches acted hypocritically, and he had also been instructed to follow the Ten Commandments, whose interpretation appeared now to be negotiable. These experiences established in Tom a sceptical attitude to religion, while the relegation of his colleagues to mere cannon fodder at the whims of remote generals encouraged a hatred of war which his son later inherited.

In France Tom was befriended by a fellow Bristolian, Charles Coghill, who after demobilisation in 1919 introduced Tom to his sister Gertrude, Peter’s mother. Gertrude had been born in 1895 in Shropshire close to the Welsh border, where her father was a physician. It was through her father’s side that Scotland could claim its quarter of Peter Higgs’ ancestry.

Her grandparents, Higgs’ great-grandparents, John and Alexandrina Coghill, came from Thurso, the northernmost town on the British mainland. They had two sons. The elder, John George Sinclair Coghill, Peter Higgs’ great-uncle, himself had scientific distinction, collaborating at the University of Edinburgh in 1869 with James Simpson on pioneering work in anaesthesia. Peter’s grandfather was the younger brother, James Davidson McKay Coghill, who was born in Edinburgh in 1839.3

James also studied medicine, though at a less rarefied level than his brother. A general practitioner (GP) interested in tropical diseases, he spent twenty years in Ceylon (now known as Sri Lanka) until in 1891 he returned to the United Kingdom, divorced his wife, and took a post at the General Hospital in Birmingham. There he met and married a nurse—Peter Higgs’ free-spirited maternal grandmother Emily Margaret, known to everyone as Maggie, who memorably spoke with a pronounced “Brummie” accent. Maggie’s background was a Victorian classic. She was one of nineteen children, few of whom survived childhood. Her mother had given birth to her first child at age nineteen, followed by one every year until she herself died, age thirty-eight, in childbirth.4

James and Maggie had three children: James, Charles, and their elder sister, Gertrude—Peter Higgs’ mother. Their father appears to have been a typical remote Victorian patrician, leaving the children’s upbringing to Maggie. He teased her about her Brummie accent, so much so that Gertrude feared lest any child of her own one day might speak that way, or indeed with anything other than good elocution. Two of Maggie’s sisters lived in Bristol, so when her husband James died in 1906, she and the three children moved to that city to be near them.

A SOLITARY CHILD

Like many others who had experienced the horrors of the trenches, on demobilisation Tom Higgs returned home to Bristol deeply traumatised. His thoughts of the church gone, an interest in radio steered Tom towards electrical engineering. Born with natural curiosity and an enquiring mind, he was among the one in a hundred who entered university in those days. In his opinion, Oxford and Cambridge “were for the sons of the idle rich to waste their time and also that of their tutors”, so he enrolled in his hometown at Bristol University. After graduation, in 1922 he joined the nascent BBC in Newcastle upon Tyne, as deputy chief engineer for the north-east region.

Tom and Gertrude married at Christ Church in the Clifton area of Bristol in 1924 and settled in Newcastle. Seriously depressed by the trauma of fighting on the Western Front, and convinced that humankind had no future, Tom didn’t want to add to human misery by producing children. After five years of marriage, however, Gertrude managed to “sabotage their traditional method of contraception”,5 fortunately for Peter, who would be their only child.

A few months after Peter was born, the family moved to Birmingham, where they lived for the next decade. If the child is father of the man, then Peter Higgs’ tendency to be a loner who would go his own way, never mind what other people think, was the product of his early years. Peter was a sickly boy. He was born with severe eczema, so bad that at night he wore cardboard tubes encasing his forearms to prevent him from scratching the rash in bed. After a time, the eczema disappeared only to be replaced with chronic asthma. As the asthma seemed to be brought on by vigorous exercise, his parents banned him from playing with other children. This quarantine carried on beyond his fifth birthday and prevented him starting primary school in September 1934.

His father was uncomfortable with children and left Peter’s upbringing to his mother. Gertrude was now haunted by memories of her own maternal upbringing, and of her mother’s distinct elocution. Because Peter’s family had moved away from Newcastle while he was still a baby, he had escaped speaking like a Geordie—a native of that city—but only by the irony of the family ending up in Birmingham, the locus of Maggie’s fear. Her son was now “at risk of speaking Brummie English!” She insisted that Peter have private schooling to ensure that he learned “received pronunciation”.6

Because of Peter’s fragile health, his formal education was delayed as he remained at home for a year. A school inspector came to their house to ask why they weren’t sending the boy to school. As Higgs recalled, his mother had taught him “the three R’s and the Lord’s Prayer” and “convinced the guy she’d taught me as much as was reasonable for a five-year-old child to learn”. More than reasonable, even, for by the time he started school in 1935, age six, he could already read and write fluently and was so far ahead of his contemporaries that he was put in a class of children two years older than himself. “My health problems gave me a head start”, he said, adding: “I grew up a rather isolated child.”7

This isolation helped determine his personality. On the one hand it amplified some of the disadvantages of being an only child: a tendency to be socially distant and ill at ease with strangers or in groups. It also developed a single-mindedness that would make it hard for him to compromise when circumstances were not, in his view, ideal. More positively, this early experience of learning on his own helped establish a lifelong love of scholarship and independent study. Gifted with an excellent memory, he accumulated a wealth of knowledge, with interests in politics, history, art, and food, all of which in his adult life made him a welcome companion for those with whom he felt at ease.

Within a year Higgs’ belated schooling was interrupted when in 1936 he had bronchitis and then double pneumonia, which put him in bed for six weeks. This happened three times at intervals of two years—at age seven, then at nine, and finally in 1940 at age eleven. This was at a time before antibiotics. His father, as was common back then, was a heavy smoker. On the third occasion, the family doctor finally realised that this was part of the problem and warned, “If you want your son to live, don’t go near him while you’re smoking”. Not surprisingly, Peter Higgs himself never smoked.

Higgs’ mother came from a strict Episcopalian background, where she had received “a taste of Christianity enough to think she should do something about my religious upbringing”. In addition to having taught him the Lord’s Prayer, she read him Bible stories “to make sure I wouldn’t go to Hell!” By age nine, however, he suddenly realised “I didn’t know why I was doing this” and stopped listening. “Having survived the year without being struck by a thunderbolt I called myself atheist or agnostic.”

The hardship which Tom Higgs had experienced during childhood, an era when the workhouse was ever present in the background, had taught Tom to live frugally and responsibly, as a role model for his younger cousin John, and had given him a rigid sense of right and wrong. Tom’s experiences would fuse in his son and, together with Peter’s isolation from other children in his early years, help to mould the scientist’s character and life as a loner.8

Most children who have no siblings learn social politics from their interaction with playmates and school friends, but Higgs’ early education in Birmingham had been as much from home as from school and, secluded from much wider merrymaking, he had to find ways of self-entertainment. His father’s bookshelves contained several texts on engineering from his student days at Bristol University. Thanks to this home library, Peter taught himself basic trigonometry, algebra, and calculus “before anyone at a school I went to taught it to me”. He attributes his dedication to mathematics as a direct result of his circumstances: “Physical health problems enabled me to forge ahead of my contemporaries, in maths especially.”

THE COTHAM SCHOOL ALUMNUS

In 1940 Higgs gained a place at Halesowen Grammar School, just beyond the western fringe of Birmingham where the family was living. He found it a pleasure to be at a good state school—“and one for pupils of both sexes”—where he mixed with children from various social classes. He recalled, “Some of them spoke with Brummie-type accents, which I was no longer likely to acquire to any significant extent”. Classes were frequently interrupted by spells in the air-raid shelter during the Battle of Britain.9

After only two terms at Halesowen, news arrived that the BBC were shifting his father to Bristol. The BBC had decided to move its headquarters from London, which it thought was going to be bombed to destruction in the next stage of the war, to somewhere safer, and judged that Bristol, 120 miles westwards, would be sufficiently far from German aircraft. But they were wrong. On Good Friday 1941, just hours before Tom—by now a senior engineer—and his wife prepared to return to the city of their childhood, its medieval centre was destroyed by Luftwaffe bombing.

They found a house much bigger than they would normally have been able to afford because the owner, who was scared by the bombing and had moved out into the countryside, was letting it at a very modest rent. The house was in Stoke Bishop, an affluent suburb on the way out to Avonmouth. While there the Higgs family had to move out for a couple of days and stay with friends because a German aircraft returning from an attack on the oil storage facilities at Avonmouth had jettisoned one of its bombs in woodland across the road from their house. The bomb disposal officer said the device was “ticking like a clock”, but when he dealt with it, he discovered it was faulty. He thought it had been built in Czechoslovakia by workers who didn’t want to help the Nazis and were sabotaging the ordnance.

A consequence of the blitz of Avonmouth and Bristol was that the BBC decided it had made a mistake to relocate there. By October 1941, Higgs’ father had been moved away, along with lots of other staff, to Bedford, which is where they set up the new BBC headquarters, in the rural east of England. Although closer to Germany, and only fifty miles from London, it wasn’t a military target.

Higgs and his mother continued to live in Bristol for the next five years, separated from his father because the accommodation available in Bedford was far too small to house families. They moved to a flat at 102 Coldharbour Road in the same Redland area of Bristol where Tom had grown up. The absence of his father in Bedford during the war—he visited the family at weekends whenever possible—helped quarantine Peter from tobacco smoke, and by age fourteen his respiratory problems were gone. His father eventually quit smoking after the war. In the postwar Labour government, Chancellor of the Exchequer Stafford Cripps imposed a huge tax on tobacco. Tom Higgs, whom Peter described as a staunch Tory, stated, “I’m not going to contribute to a load of socialists!” and never smoked again. “He was foul-tempered for about six months, and then came out of it.”10

In Bristol, the intention was that Peter should attend Bristol Grammar School, where his father had been a pupil. However, his father took a dislike to the headmaster, so they settled for the most academic of the local state schools, then called Cotham Secondary School. During their decade in Birmingham, his mother had successfully ensured that he went to middle-class schools and spoke with “received pronunciation”. Now at Cotham, he picked up the local intonations. The gentle Bristolian burr with its rhotic regal pronunciation of “off” as “orf” would remain with him thereafter.

Cotham School played a crucial role in Higgs’ life. Each morning, pupils and staff assembled in a hall that doubled as a gymnasium. Children were in the body of the auditorium while the staff conducted the singing of “dreadful hymns” from a platform at the front. On his first day, standing at the back of the assembly hall, Higgs scanned the honours board that listed distinctions won by former pupils. One name, which appeared several times, attracted his attention: Paul Adrien Maurice Dirac. That made Higgs curious: “What had this boy done?”11

He soon discovered that Dirac was a Swiss national whose father, Charles, from the Valais in Switzerland, had become the principal teacher of French at the school. Paul’s mother was a Bristolian; he and his father became British by naturalisation in 1919 when Paul was seventeen.12 Higgs’ discovery of Dirac’s achievements came later with one of Higgs’ own prizes: a book token with which he bought a popular work titled Marvels and Mysteries of Science. From that book he first learned of the “new-fangled quantum mechanics”, which Dirac had pioneered. Higgs discovered too that his first physics teacher, Mr Willis, had thirty years earlier also taught Paul Dirac.