by John Gribbin
Furthermore, the uncertain, probabilistic nature of the quantum world means that if two identical wavicles are treated in an identical fashion (perhaps by undergoing a collision with another type of wavicle), they will not necessarily respond in identical fashions. That is, the outcome of experiments is also uncertain, at the quantum level, and can be predicted only in terms of probabilities. Electrons and atoms are not like tiny billiard balls bouncing around in accordance with Newton’s laws.
None of this shows up on the scale of our everyday lives, where objects such as billiard balls do bounce off each other in a predictable, deterministic fashion, in line with Newton’s laws. The reason is that Planck’s constant is incredibly small: in standard units used by physicists, it is a mere 6 × 10−34 (a decimal point followed by 33 zeros and a 6 [i.e., 0.0000000000000000000000000000000006]) of a joule-second. And a joule is indeed a sensible sort of unit in everyday life—a 60-watt light bulb radiates 60 joules of energy every second. For everyday objects like billiard balls, or ourselves, the small size of Planck’s constant means that the wave associated with the object has a comparably small wavelength and can be ignored. But even a billiard ball, or yourself, does have an associated quantum wave—even though it is only for tiny objects like electrons, with tiny amounts of momentum, that you get a wave big enough to interfere with the way objects interact.
It all sounds very obscure, something we can safely leave the physicists to worry about while we get on with our everyday lives. To a large extent, that is true, although it is worth realizing that the physics behind how computers or TV sets work depends on an understanding of the quantum behavior of electrons. Laser beams, also, can be understood only in terms of quantum physics, and every compact disc player uses a laser beam to scan the disc and “read” the music. So quantum physics actually does impinge on our everyday lives, even if we do not need to be a quantum mechanic to make a TV set or a hi-fi system work. But there is something much more important to our everyday lives inherent in quantum physics. By introducing uncertainty and probability into the equations, quantum physics does away once and for all with the predictive clockwork of Newtonian determinism. If the Universe operates, at the deepest level, in a genuinely unpredictable and indeterministic way, then we are given back our free will, and we can after all make our own decisions and our own mistakes.
At the beginning of the 1960s, the two great pillars of physics stood in splendid separation. General relativity explained the behavior of the cosmos at large and suggested that the Universe must have expanded from a super-dense state, colloquially known as the Big Bang. Quantum physics explained how atoms and molecules work and gave an insight into the nature of light and other forms of radiation. One young physicist, taking his first degree at Oxford University, would have been given a thorough grounding in both great theories. But he would hardly have suspected that over the next half century he would play a key role in bringing the two theories together, providing insight into how they might be unified into one grand theory that would explain everything, from the Big Bang to the atoms we are made of.
* Strictly speaking, it is a velocity—a quantity that specifies speed and direction. For our purposes, it is easier to refer to velocities as speeds.
† In everyday language, time dilation means that a clock moving relative to an observer runs slow, and length contraction means that an object moving relative to an observer shrinks in the direction of its motion.
3
GOING UP
The year 1959 started with a bang: January 2 saw the thirty-two-year-old Fidel Castro sweeping to power in Cuba; a month later, Buddy Holly died in a plane crash and Indira Gandhi became the leader of India’s ruling Congress Party. By the spring, the world’s first hovercraft was under construction on the Isle of Wight, two rhesus monkeys had become the first primates in space, and the writer Raymond Chandler had died at age seventy. Meanwhile, in a small city in Hertfordshire a seventeen-year-old schoolboy named Stephen Hawking was getting ready for the Oxford entrance examination in a large, cluttered bedroom in his parents’ rambling Edwardian house. Obtaining a place at Oxford University was no easy task. A potential candidate had two alternatives—an entrance examination taken in the upper sixth, before A Levels, or the same examination taken in the seventh term, provided very high A Level grades had been obtained. The former route meant that a successful candidate could go straight to Oxford after the summer vacation; the latter necessitated waiting until the following October.
Stephen and his father settled on the first alternative, and he was entered for the examination toward the end of his final year at St. Albans School. The intention from the start was that he was going for a scholarship, the highest award offered by the university. The award provided a number of titular privileges, and, more important, a percentage of the cost of putting a student through Oxford was paid by the university. A student failing to obtain a scholarship could be awarded an exhibition, which was less prestigious and brought with it a smaller contribution to the costs of education. Last, a candidate could be offered a place at the university but with no financial assistance at all and the student was then known as a “commoner.”
Over the previous year, father and son had engaged in endless arguments over the choice of university course. Stephen insisted that he wanted to study mathematics and physics, a course then known as natural science. His father was unconvinced; he believed there were no jobs in mathematics apart from teaching. Stephen knew what he wanted to do and won the argument; medicine had little appeal for him. As he says himself:
My father would have liked me to do medicine. However, I felt that biology was too descriptive, and not sufficiently fundamental. Maybe I would have felt differently if I had been aware of molecular biology, but that was not generally known about at the time.1
Frank Hawking lost the argument over Stephen’s choice of degree course, but he was determined to see his son obtain a place at his old college, University College, Oxford. However, it is clear that Dr. Hawking was not, even at this stage, fully convinced of Stephen’s ability and believed that he had to pull strings to get him in. He evidently decided to take the initiative. Just before the scheduled entrance examination during the Easter vacation, he arranged to take Stephen to meet his prospective tutor at University College, Dr. Robert Berman. As Berman himself recalls, the sort of pressure Hawking senior was applying would usually have put him off the candidate immediately. However, Stephen sat for the exam and did so extraordinarily well that Berman and University College soon warmed to him.
The entrance examination was pretty tough. It was spread over two days and consisted of five papers in all, each of which was two and a half hours long. These included two physics and two mathematics papers, followed by a paper that tested candidates on their general knowledge and awareness of current affairs and world issues. A typical question would have been something like “Discuss the possible short-term global consequences of Fidel Castro’s takeover of Cuba.” It was doubted at the time whether a seventeen-year-old should be expected to have very strong opinions on such matters at all, and some at the university even doubted the desirability of such opinions. Dr. Berman, for one, would have been more impressed, he has said, by Hawking’s knowledge of the England cricket team than his views on contemporary politics.
After twelve and a half hours of theory examinations and a physics practical paper came the interviews. First there was a general interview at which the candidates were grilled by the master, dean, senior tutor, and fellows of the subject. These took place in the Senior Common Room. The prospective students were led in individually to face stern appraisal by the panel and were expected to give intelligent answers to a series of obtuse questions. The purpose of this, like that of a job interview, was to find out a little more about the character of the candidate. Following the general interview, a specialist interview was held in Dr. Berman’s office, during which Hawking was questioned on his knowledge of physics.
The
interviews and examinations over, the candidates returned to their various schools around the country to await the results and get on with their A Levels. Meanwhile, the tutors marked the papers and conferred on the matter. If University College wanted Hawking, they had first choice of offering him a scholarship because he had placed them at the top of his list in his application. If they decided they did not want to award him a scholarship or an exhibition, then other Oxford colleges on his list could take up the option. If no one wanted to give him an award, the choice went back to University College to take him as a commoner if they wished.
Ten days passed before he heard anything from them. Then came the invitation to return for another interview. This was a promising step forward. It meant that they were taking his application seriously and that he had a very good chance of obtaining a place. Little did he know that he had scored around ninety-five percent in both his physics papers, with only slightly lower percentages in the others. A few days after the second interview, the all-important letter fell onto the Hawkings’ doormat. University College was offering him a scholarship. He was invited to enroll at Oxford University the following October, the only condition being that he obtain two A Level passes in the summer.
It has often been said that there is a certain light in Oxford, a wonderful interplay between sunlight and sandstone, which, like the comparably beautiful cities of Italy and Germany, has inspired the work of poets and painters down the centuries. The city center is totally dominated by the presence of the university—a ubiquitous thing, without nerve center or organized structure. The colleges are to be found in a random scattering with the rest of the town weaving around it. The architecture displays as little organization as the geography, dating from medieval times to the late twentieth century. On summer days, with the sunlight strong against the stonework and the river dotted with punts, their navigators sweeping a pole into the sparkling water, and those on the grassy banks lifting a glass of champagne to their lips, it can, if you let it, seem like an earthly paradise in freeze frame.
In the late fifties and early sixties, Oxford, as a microcosm of British society, was on the brink of great change. When Hawking arrived at the High on his first October Thursday as an undergraduate, the university had in many respects changed little since his father’s time or, indeed, for the past few hundred years. University discipline had relaxed somewhat since the end of the war. Before then, students had been forbidden to enter the city’s pubs and could, if caught, be expelled from them by the university police, known as the Bulldogs. Women were not allowed in male students’ rooms without written permission from the dean, who would specify strict time limitations and conditions in a letter sent to the head porter, who would then rigorously uphold the dean’s instructions. All this changed when servicemen returning from the war entered the university either as freshmen or to restart courses interrupted by the fighting. Naturally, they were unwilling to accept such draconian restrictions and gradually the rules were relaxed.
Students vied for rooms in college, but Hawking was lucky in that, being a scholar, he took priority and managed to keep in residence in college rooms throughout his three years at Oxford.
Most Oxford colleges are built in the form of a number of quads, each with a lawn at the center and paths around and across the grass. From the quads, staircases lead off into the buildings, and the students’ rooms are on a number of levels up to the top of each staircase. Students in college had their rooms cleaned for them and their general domestic duties handled by college servants, or “scouts.” Scouts were also responsible for making sure that hungover young men and the occasional young woman made it to breakfast between the regulation times of 8:00 and 8:15, so as to avoid facing a locked dining-hall door. Scouts addressed the students as “Sir” or as “Mister Such-and-Such” if attempting to inject a note of disdain into their voices. They in turn were addressed by their surnames, in true master-servant fashion.
The intake at Oxford was still largely male and from the country’s private schools, and the majority of those were from the top ten, including Eton, Harrow, Rugby, and Westminster.
The number of students from middle-class and working-class backgrounds was beginning to increase, but in many respects the class system took on a greater refinement and a sharper profile at Oxford University. There were definite lines of demarcation. The friendships and relationships capable of crossing those invisible boundaries were still amazingly few. The twain very rarely met.
In one camp were the elite, the children of the aristocracy and heirs to “old money,” the Sebastian Flytes of this world; they made up a substantial proportion of students at Christchurch and, to a lesser extent, Balliol. The privileged spent their often considerable allowances largely on entertaining their chums from school who had gone up with them or friends who had chosen to go to the “other place,” Cambridge. They looked upon those from minor private schools such as St. Albans as a lesser breed, lumping them in with the lowest of the low—ex–grammar school boys. Despite literature’s tendency toward exaggeration, it was still all very Brideshead Revisited. On the other side of the divide, the “Northern chemists” and the “grammar school oiks” made do on their scholarships and grants, forfeiting quails’ eggs and champagne for pork pies and beer.
The two groups looked surprisingly similar in many respects. In the late fifties, baggy trousers and tweed jackets were in fashion for academic young men whatever their background. The difference was that for a privileged few the jackets came from Savile Row and the baggy turn-ups from Harrods. At the college balls held each summer, the female companion of an Old Harrovian or Etonian would, in all probability, be the daughter of a baron or a duke, wrapped in the best silk. Meanwhile, at the same functions, the middle classes gathered together with others of their own kind, sipping at rarely sampled champagne.
A simple point of reference illustrates the changes about to hit Oxford soon after Hawking went up, encapsulated by one of his contemporaries. “When we arrived in Oxford,” he said, “anybody who was anybody rowed and never wore jeans. When we left, anybody who was anybody never rowed and did wear jeans.”
Changes were afoot everywhere. Beat poetry from San Francisco was beginning to have an influence. The Labor Party was growing in popularity. The old values, the class system in particular, were beginning to look anachronistic, at least among the intelligentsia. There was no desire to “storm the citadel” (that would come a decade later and in a different city), but the Zeitgeist was definitely on the move. When it came down to it, Hawking’s type of person found the whole infrastructure of Oxford as a microcosm faintly amusing, an ethos which would, in peculiarly British fashion, lead to Beyond the Fringe and Monty Python rather than blood in Parisian gutters.
Despite its many charms, Hawking’s first year at Oxford was, by all accounts, a pretty miserable time for him. Very few of his school contemporaries and none of his close friends from St. Albans had gone up the same year. In 1960 Michael Church arrived, and John McClenahan went to Cambridge. Many students in Hawking’s year had completed national service before going up and were consequently a couple of years older than he. (He had avoided the draft himself by only a few months when it was scrapped by Harold Macmillan’s government.)
Work was a bore. He had very little difficulty solving any of the physics or mathematics questions his tutors gave him, and he went into a downward spiral of bothering very little and finding meager satisfaction in easy victories. The system at Oxford made it easy for someone like Hawking to slide into apathy. Students were expected to attend a number of lectures each week and a weekly tutorial in which problems given during the previous tutorial were gone through. Apart from these commitments, students were left largely to their own devices.
On top of this freedom, the examination structure was loose and eminently open to exploitation if you were of Hawking’s caliber. The only crucial examinations were set by the university, as opposed to the college, and took place at the end of the
first year and again in the final year. The degree was awarded solely based on the student’s performance in finals. There were also college exams at the beginning of each new term to test the students on both the previous term’s work and their personal studies during the vacation. These were called collections and were marked by the students’ own tutors. As Hawking relates:
The prevailing attitude at Oxford at that time was very anti-work. You were supposed either to be brilliant without effort or to accept your limitations and get a fourth-class degree. To work hard to get a better class of degree was regarded as the mark of a gray man, the worst epithet in the Oxford vocabulary.2
Hawking knew that he was in the former category and determined to live up to the image. During his first year he attended only mathematics lectures and tutorials and completed college exams solely in mathematics. As his tutor now freely admits, the physics course at the time was little more than a repetition of A Level work and of limited use to the Hawkings of this world.
There has arisen a veritable folk tradition of anecdotes about his intuitive understanding of the subject at university, stories reminiscent of the early prowess of the boy-Mozart. One of his contemporaries who shared tutorials with Hawking recalls an incident that left a lasting impression on him. They had been given some problems by the tutor to bring to the next tutorial. No one in the group could do them except Stephen. The tutor asked to see his work and was immensely impressed with his proof of a particularly difficult theorem and, complimenting him on the achievement, handed back the paper. Without the slightest hint of arrogance Hawking took back his work, wadded it into a ball, and lobbed it into the waste-paper bin in the far corner of the room. Another member of the tutorial group said later, “If I had been able to prove that in a year, I would have kept it!”