WITHIN A WEEK I had moved up to Cambridge and found a room in a house in the Fens, so called because it was originally a marshy area outside Cambridge. It was still winter, and cold and damp. In my room was a monstrous gas fire, controlled by a large metal box, which gobbled up all the shillings I could feed into it. I had to make regular trips to Barclay’s Bank on Benet Street, where I had opened an account, in order to acquire more bags of shillings. Being used to modern heating appliances in Denmark, I soon moved my studies to the library above the Arts School on Benet Street, where the Theoretical Physics Department was located, as well as the Mathematics Department. There I would sit every day in relative warmth, clad in my black gown, which was mandatory apparel for students when in official university buildings and on the grounds. I was surrounded by other black-clad students seeking warm working conditions. The walls of the library were lined with hundreds of books in mathematics and physics, and the chief librarian in his grey smock was a friendly man who was helpful in retrieving the papers that I needed for my research.
At lunchtime, I would walk down King’s Parade to the Great Hall at Trinity College, still wearing my black gown. I felt quite lonely since I had not yet managed to get to know any fellow students. In the library, everyone kept to themselves, studying intently and in silence. The quality of the lunch at college left a lot to be desired. It usually began with soup. One day I accidentally splashed my Trinity College tie with the soup, and soon a hole appeared there. What was the soup doing to my stomach! The dining hall at Trinity was one of the largest and most impressive of any of the colleges at Cambridge. There was a lounge for students on the second floor with a portrait of Sir Isaac Newton peering down at us from the wall, along with other notable Trinity scholars. I also visited the Wren Library, which had valuable physics manuscripts and had acquired a musty smell from the thousands of ancient books in the library stacks.
A few days after arriving at Cambridge, I saw Fred Hoyle in his rooms at St. John’s College. Hoyle, who was about forty at that time, was quite congenial and asked me to sit down in a chair facing his desk with a large oil painting of himself behind it on the wall. I wondered whether all his students were forced to sit during tutorial sessions and contemplate Hoyle’s blunt Yorkshire features in duplicate while he sat in an easy chair nearby.
Everyone at Cambridge referred to him as “Mr. Hoyle” because he had never felt the need to obtain a Ph. D. It was not uncommon for well-known academics in science in those days to avoid obtaining a doctorate. Hoyle was the only person at Cambridge besides Dennis Sciama, and a visiting physicist named Felix Pirani, who was actively engaged in research on relativity theory and cosmology, and since I was now already known around the university as the person who had corresponded with Einstein and worked on unified field theory, Hoyle was an obvious choice for my supervisor. At the time, Hoyle was working in collaboration with Margaret and Geoffrey Burbidge and William Fowler at Caltech on the origin of matter in stars and the early universe. The collaboration produced a famous paper in 1957,which derived the abundances of nuclear elements in the early universe and described the production of heavy elements in stars. The paper, entitled “Synthesis of the Elements in Stars,” became so famous that it was widely referred to as “B2FH,” meaning “Burbidge squared, Fowler, Hoyle.”
Relativity and gravity were not popular research topics in the 1950s. Most of the activity in fundamental theoretical physics was concerned with atomic and nuclear physics, and also the very active field of particle physics. There was a dearth of experimental evidence for the validity of Einstein’s gravity theory. There were only three classical tests of the theory: the bending of light, which had been verified in 1919 and, more convincingly, at the solar eclipse of 1922; the perihelion advance of Mercury;* and the difficult-to-verify observations of gravitational red shift by the sun and the dwarf star Sirius B. In contrast, the more popular field of particle physics had a wealth of experimental possibilities at the high-energy accelerators that were being built around the world. Indeed, the editor of the prestigious American physics journal Physical Review,Samuel Goudsmit, had threatened to ban all papers on gravitation in the journal. Since I had been actively pursuing unified field theory, which involved gravitational research, I wanted to continue this research at least for the first year or two at Cambridge, even though it wasn’t in the current mainstream of physics.
At our first meeting, Hoyle wanted to discuss my future right away, and I related to him the usual story of the Einstein correspondence and how I was working on Einstein’s unified field theory.
As I anticipated by now, Hoyle said, “Well, John, in my opinion, Einstein is wasting his time with this unified field theory business. For that matter, so is Schrödinger.” This was delivered matter-of-factly in Hoyle’s thick Yorkshire accent.
I thought it prudent to remain silent.
“It’s my understanding that you don’t have undergraduate training,” he said, changing tack.
“I’ve discussed this with Dennis Sciama,” I replied. “As you know, he matriculated me without an undergraduate degree.”
Hoyle eyed me through his thick-lensed glasses, and after a few moments of hesitation, he said, “Perhaps you should consider taking the tripos exams, and perhaps even spending four years studying for the Mathematical Tripos Part II, before continuing your physics research. After all, a physicist needs a proper training to be able to produce useful research that can make a mark on the physics community. Don’t you think you should do this?” I shuddered at the thought.
“Personally I think I’d be wasting my time. I would prefer to continue working towards my Ph. D.because I believe I have enough technical ability to succeed.”
Hoyle leaned back abruptly in his chair and didn’t look convinced. “ You realize you’re taking a chance, and you could well fail?” he continued. “I think you should contact Dr. Felix Pirani who is presently visiting Cambridge and doing research in relativity theory. He can advise you on your best course. He is a very competent physicist, well versed in relativity theory.”
I wondered why Hoyle was passing some of the responsibility for me onto the shoulders of Felix Pirani, and I began to feel uneasy about my future at Cambridge.
I was officially associated with a tutor at Cambridge who was responsible for my well-being at the college. Four other first-year students and I met him in his comfortable rooms at Trinity one evening, where we stood around sipping sherry. The tutor informed us about various issues regarding college life and the rules that we had to abide by. In particular, we were told to wear our gowns in the evenings in order to distinguish ourselves from Cambridge residents, which emphasized the ritualistic class separation of “town” and “gown.”
I had a problem that I suspected the other students in the tutor’s rooms did not have: I needed to find financial support because the money from the British government would come to an end within a month. Mr. Greenall had advised me by letter to approach the Nuffield Foundation in London, which provided student scholarships through the Massey-Harris-Ferguson farm equipment foundation in faraway Canada. I arranged an interview by letter with a Mr. Sanderson, the assistant director of the Nuffield Foundation, and took the train to London to meet with him. He was sympathetic to my situation and, as others had been, was impressed by my correspondence with Einstein and the letter of recommendation from Schrödinger. Within two weeks, I was informed that I had been awarded a Massey-Harris-Ferguson Foundation grant amounting to ten pounds per week, which in those days was enough to keep a student alive.
I spent some time pondering my unusual and perhaps precarious situation at Cambridge, and began to form a plan to ensure that I would be left alone in the three or four years it would take me to finish my Ph. D. I decided to write more papers and submit them to the Proceedings of the Cambridge Philosophical Society, a prestigious old physics and mathematics journal. (I did not continue working on the papers I had sent to Einstein on his unified field theory. I had finally realized that his program for a unified field theory was a failure, and I wished to move on to my own attempts to modify Einstein’s gravity theory.)
I spent many days at the Arts School library that winter, working on my first modified version of Einstein’s gravity theory. I was trying to change Einstein’s theory because I felt that there were deeper mathematical and physical aspects of his concept of gravity that had not been mined as yet. My idea was strikingly original. I had formulated a complex symmetric Riemannian geometry,* and the first paper was of a purely mathematical nature. I believed that this was possibly the simplest way to modify Einstein’s theory of gravity and still remain within a purely geometrical structure of spacetime.
I knew that my supervisor, Fred Hoyle, was not terribly supportive of modifying Einstein gravity, either to develop a unified theory of gravity and electromagnetism or to simply modify relativity within the context of pure gravitation. In addition to his projects on the origin of matter in stars, Hoyle was busy working with his colleagues at Trinity College, Thomas (“Tommy” ) Gold and Hermann Bondi, on the steady-state universe cosmology, which was an alternative to the popular Big Bang model of the beginning of the universe. However, I was not interested in working on the steady-state model. The mathematical structure of mymodified gravity theory was very appealing to me, and as it turned out many years later, it would have relevance for developments in quantum gravity theory.
To my delight, I received notice from the Proceedings of the Cambridge Philosophical Society that they had accepted my first paper on modified gravity. The journal editor suggested that I talk with a mathematician at Trinity, who turned out to be an English baron. He was enthusiastic about my paper and only suggested one change: replacing a word that I had used incorrectly. I was pleased that it was only a mistake in English, not in the complicated mathematics I had used. Emboldened by this first success, I wrote two more papers, brazenly calling one of them “The Foundations of a Generalized Theory of Gravitation.” Now I had a full-blown modification of Einstein’s gravity theory. I submitted these papers to the same journal and they too were accepted for publication!
When he heard about the acceptance of these papers, Hoyle changed his mind about my needing to labour for several years in order to sit the horrendous tripos exams. In a subsequent meeting, I detected a shift in his attitude: from then on, Hoyle treated me more like a colleague than a student. For an hour, he would expound his latest ideas in his steady-state model, and describe his ongoing dispute with the Big Bang establishment. The steady-state model was based on the “perfect cosmological principle,” originally proposed by Gold and Bondi. This principle states that not only does the universe look the same in every direction and matter is uniformly distributed throughout the universe, but it also looks the same at any time in the evolution of the universe. This is very different from the Big Bang theory, in which only the first two principles apply—known as the principles of isotropy and homogeneity.
It seemed to me that this perfect cosmological principle was indeed a simple, beautiful idea. In order to maintain it, Hoyle and his collaborators had published papers postulating that minuscule bits of matter were continuously created in voids in space. It didn’t take the creation of much matter to continually refill the universe. In the steady-state model, there was no beginning to the universe, and yet it still had to explain Edwin Hubble’s astronomical observations of the expansion of the universe and the recession of galaxies. Hoyle, Gold and Bondi postulated that, in order to conserve energy, matter was continuously created as the galaxies receded into the infinities of space. This was in direct contrast to the Big Bang model, championed by leading cosmologists such as Georges Lemaître and George Gamow, in which the universe had a singular beginning with an infinitely dense point of matter and, according to Lemaître, a huge explosion. Yet, ironically, it was Hoyle who gave what was originally known as the “dynamic evolving model” its catchy name. In the late 1940s, during a famous series of talks on the BBC, Hoyle dismissively referred to the primal explosion as the “Big Bang,” and the name stuck.
During our tutorials, Hoyle wasn’t really very interested in discussing the papers I was writing and publishing. He would sit in his easy chair under his portrait and talk rapidly about new developments in his steady-state model. He would stop his monologue occasionally and peer at me through his thick glasses and ask me a question such as, “Well, what do you think of these ideas about how to treat geodesic motion of particles in the steady-state model?”
My mind would race to find something intelligent to say, although I wasn’t working on the subject. I would finally begin to sputter out an answer—“Well, I think that maybe you should . . .” Hoyle would then suddenly leap out of his chair, look nervously at his watch like the White Rabbit, grab his black gown and announce, “I have to leave! I mustn’t be late for my eleven o’clock lecture!” We would then rush through St. John’s College, out into Trinity Street and up the street to the Arts School where he was to give his lecture, without saying a word.
Following Hoyle’s suggestion, I did seek out Felix Pirani, a scholar in his late twenties who was doing a second Ph. D. at Cambridge, having already completed one under the supervision of the Toronto relativist Alfred Schild. Felix lived with his wife in a house on the outskirts of Cambridge. He was also skeptical about my prospects of succeeding at Cambridge, and voiced the opinion that I should take the tripos exams. Indeed, during one of my visits to his house, he became quite voluble and aggressive on the subject. I became upset, the evening ended in a shouting match, and we parted on not-very-friendly terms. However, as with Hoyle, when I later informed him that my papers were being published in the Philosophical Society Proceedings, Pirani seemed to change his mind and we began to discuss serious issues in relativity theory together.
After my first year at Cambridge, with three published papers on my resumé, I was pretty much left to my own devices. I attended only two courses. I sat in on Paul Dirac’s inspiring course on quantum mechanics and later decided to repeat the experience all over again. Dirac’s exposition of quantum mechanics was like the construction of a beautiful symphony. It was so logical in its development that, despite Einstein’s objections to the theory, Dirac’s description convinced many physicists that quantum mechanics possessed its own beauty. The other course was on boundary value problems in potential theory given by an applied mathematician, Eggleston. This was an interesting subject to me in applied mathematics, which would stand me in good stead when I prepared my Ph. D. thesis on classical gravity theory.
One evening I attended a party at a big house at 9 Adams Road in an upscale residential area on the outskirts of Cambridge. This house enjoyed a certain notoriety in Cambridge circles, for its parties were an opportunity for young students to pick each other up, and engage in some serious drinking. The upstairs of the house was occupied by Professor Francis Roughton, a celebrated physiologist at Trinity. In the downstairs lived his ex-wife, Dr. Alice Roughton, an equally well-known family physician and psychiatrist, who regularly wore farmer’s clothes and heavy boots that she had inherited from a former RAF pilot. She encouraged her psychiatric patients and an odd assortment of foreign students to share her quarters. A young woman caretaker helped her with the household.
On Friday nights Dr. Roughton held her weekly soirées, where the notable event would be the serving of the cheese, a massive chunk of Stilton from which issued forth an obnoxious smell. At one of these evenings, Dr. Roughton offered to take me in as one of her resident students. I was happy to escape my cold and unfriendly room, so I promptly moved in, taking a bed in a dormitory-sized room with three other male students. At night, Dr. Roughton, dressed in a leather-and-sheepskin RAF suit and helmet, slept on the veranda outside our room, with its doors wide open, even in the middle of winter. Her loud snoring often kept us awake.
One of the students in our large shared room was a Greek whose distinguishing feature was his black academic gown, which had only a few tatters of cloth left, hanging from his back. He was often in trouble and was fined for not wearing his regulation black gown at the university. Several times he borrowed Professor Roughton’s bicycle, which was always parked outside the house, and had to face the fury of the professor, who bicycled to Trinity every day after lunch. This student was also the official photographer of the university newspaper, the Varsity, because this gave him opportunities to photograph young ladies privately in the nude.
Due to a shortage of funds and a lack of clothes-washing facilities at Adams Road, the aromas in the room at night where we slept sometimes became overpowering. One of the students was an upper-class Englishman, who had attended Winchester College before coming up to Cambridge. One night when I was retiring and removing my socks, he parodied an incense-bearer, parading around my bed, swinging his arm and chanting in Latin.
An African student doing a Ph. D. in history also lived at the Roughton house. He claimed to be the son of a tribal chief in Nigeria. He was often quite hostile towards the rest of us, and would play the grand piano for hours at night in a large living room adjoining the room where we slept. When I suggested that he cease his piano playing earlier so that we could get some sleep, he rudely dismissed me. This fellow—tall and handsome, with tribal scars on his cheeks—was hugely popular with the young ladies who attended the parties at the Roughton residence.
When my tutor at Trinity heard about my living at 9 Adams Road, he summoned me to his rooms. Wasn’t I aware that this notorious house was out of bounds for Cambridge students? This ended my six months of interesting and cheap—indeed, free—lodgings at the Roughton residence. On several occasions I had dutifully presented my rent money to Dr. Roughton while she was in the kitchen preparing her Stilton-cheese feasts. But she always refused to take any payment.
I met my future wife, Bridget Flowers, for the first time at one of the weekly dances held at the Cambridge City Hall, and later we coincidentally met at one of the weekly Adams Road cheese soirées. I was pleased to happen upon her sitting on the stairs leading up to Professor Roughton’s apartments, nursing a drink. We made a date to meet the next day on the bridge over the River Cam behind Trinity. This began an ongoing relationship. In 1958,my last year at Cambridge, we were married in her hometown of Norwich, in Norfolk.
After the upbraiding by my tutor, I had to search for new accommodations. I located a room in a house on the outskirts of Cambridge. In contrast to the bizarre and lively activities at Adams Road, the new household consisted of a brusque landlady, with many stern rules for her lodgers, and her meek husband. Instead of smelling of Stilton cheese and ripe socks, this house reeked of disinfectant and linoleum-floor polish.
My supervision in Hoyle’s rooms at St. John’s College had become intermittent. Hoyle’s supervision of students was generally known to be lackadaisical, as he was completely wrapped up in his own research. Hoyle eventually became famous through his research into the cosmic origin of the elements as well as his steady-state cosmology. In addition to his celebrated work on the origin of the heavier elements in stars, in collaboration with William Fowler and Geoffrey and Margaret Burbidge, he also contributed significantly to explaining how hydrogen, helium and other lighter elements such as lithium were produced in the early universe, thereby indirectly supporting the Big Bang model, which he despised.
One afternoon, Hoyle invited me to his cottage some distance from Cambridge for tea. It was a comfortable house, and his wife greeted me and a divinity student from Trinity in a welcoming way. We had tea and cakes in a sunlit room with a pleasant view of the old-English garden. After tea, we were invited to sit in the living room, where a large oil portrait of Fred Hoyle hanging above the fireplace dominated the room. As in his St. John’s College rooms, I couldn’t help being distracted by the bold stare from the portrait, while Hoyle himself, staring just as intensely, launched a verbal attack on the divinity student.
“Why do you waste time trying to prove the existence of God?” Hoyle asked abrasively. “Surely an intelligent person like you does not actually entertain notions that there is a God.”
The divinity student hesitated and said politely, “The existence of God is a belief, a matter of faith, not proof. It’s important for me to sustain this faith.”
Hoyle snorted and said, “Faith? Faith in such nonsense?”
The poor divinity student sat quietly, his face beginning to droop and turn pale, as Hoyle became inspired to greater heights in his attack.
Fred Hoyle was a notorious atheist at this time, with no patience for religion. I began to realize that I was witnessing the assassination of a Cambridge divinity student. I wondered whether Hoyle had invited him to tea simply as a form of sport, to exercise his anger at and resentment of religious beliefs, which still dominated many aspects of Cambridge college life. Hoyle’s atheism could be seen in his current main research interest—his steady-state model of the universe. In this model, there was no beginning to the universe, and galaxies were spontaneously born in a cold, dark cosmic void, doing away with the need for a creator. Hoyle despised Pope Pius XII’s support of George Lemaître’s Big Bang theory. To the pope, a beginning of the universe with a dramatic explosion proved the existence of the Creator. Lemaître himself, a priest as well as a cosmologist, eventually managed to dissuade the pope from promulgating these beliefs from the Vatican, for he did not wish to mix science and religion. But to Hoyle, the pope’s approval of the Big Bang theory was anathema.
Hoyle never addressed a word to me at the science-versus-religion tea party. I was merely the silent witness to the abusive demise of myfellow student. I was not personally affected by Hoyle’s anti-religion diatribe because my parents had rarely taken me to church as a child, and if pressed, I would have described myself as an agnostic. But I felt mortified and sorry for the divinity student. When Hoyle finished his attack, the four of us walked out into the garden, where Mrs. Hoyle showed us her magnificent beds of perennial flowers. As if nothing out of the ordinary had happened, Hoyle then transformed himself back into the convivial country gentleman and college don. There was no further talk about God.
Much later in his life, Hoyle appeared to change his atheistic stance dramatically. In his work on the evolution of stars, Hoyle discovered the need for a special excited energy state, or “resonance,” of carbon to get the chemical processes going that would produce the stable carbon nucleus that is the basis of life. Proponents of what is now called the “anthropic principle” turn the process on its head and claim that the existence of carbon-based life (e.g., humans) is proof enough that this rare carbon resonance exists. They also claim that the fundamental constants in nature have their specific values because we exist. Hoyle’s carbon resonance was discovered experimentally by William Fowler in the mid-1950s. He won the Nobel Prize for the discovery almost thirty years later, along with the theorist Subramanyan Chandrasekhar, while inexplicably Hoyle did not share in the prize.
In the 1980s, Hoyle published popular books on the origin of life, such as Evolution from Space: A Theory of Cosmic Creationism. He concluded that it would be almost impossible for life to have evolved through natural processes alone, without the guiding hand of a greater intelligence. The well-known “Hoyle’s fallacy,” in which he compared the evolutionary origin of life to be as likely as the sudden assembly of a Boeing 747 from a tornado passing through a junkyard, is often used by believers in intelligent design to bolster their position.
I felt quite isolated at Cambridge in my research, being the only active relativist there, besides Felix Pirani. Dennis Sciama, who had been one of Professor Paul Dirac’s few students, was engaged in interesting research attempting to understand the origin of inertia, the property of a body moving at constant speed until an external force changes its speed. This very basic concept in physics was described in Newton’s first law of mechanics. But the origin of inertia had always been a mystery, and had not even been properly understood in Einstein’s theory of gravity. Decades later, inertia would prove to be an important area of research in my modified gravity theory (MOG), but in the 1950s, Sciama was as alone in his research focus as I was.
During my second year at Trinity, Roy Kerr, a New Zealander, arrived in Cambridge to begin research in theoretical physics. We became friends, and he asked me for advice on what research topics he should pursue. Roy confessed that his knowledge of physics was limited. In New Zealand he had been working as an applied mathematician, solving differential equations associated with myxomatosis, a disease that was endemic among the rabbit population there. Roy was a brilliant mathematical physicist who had great talent for solving differential equations in applied mathematics. I told him that perhaps he should work on Einstein’s gravitation theory. I explained that he didn’t need to know much physics, but that there were lots of equations to solve.
I also pointed to the problem of the motion of particles in Einstein’s gravity theory, as determined by the non-linear field equations. As Einstein, Infeld and Hoffmann had shown in a celebrated paper published in Annals of Mathematics in 1938, the motion of bodies in Einstein’s gravity theory was not a separate postulate but could be derived from the theory’s basic field equations. In contrast, Maxwell’s field equations for the electromagnetic field were linear differential equations, and the motion of electrically charged bodies was determined by an additional postulate called the Lorentz force law. I was working on the problem of the motion of particles in Einstein’s theory myself for part of my Ph. D. thesis. In particular, I suggested to Roy that he work on the motion of spinning particles, as the Greek physicist Achilles Papapetrou and others had been doing, as this work looked promising. Roy Kerr’s first research project was to work out the static, spherically symmetric solution of my first modified gravity theory, which I had published in the Proceedings of the Cambridge Philosophical Society. Indeed, he wrote an excellent paper on this, which was published in Il Nuovo Cimento. It appeared in 1958 and was titled “On Spherically Symmetric Solutions in Moffat’s Unified Field Theory.” Roy eventually became famous for discovering the exact, rotating black hole solution in Einstein’s gravity theory, one of the few exact solutions of the field equations of the theory. I like to take a small morsel of credit for Kerr’s great success.
Later at Cambridge, I had the misfortune of discovering serious mistakes in a paper published by Einstein and Leopold Infeld in 1949 in the Canadian Journal ofMathematics. The editors of the journal felt this paper, “On the Motion of Particles in General Relativity Theory,” was so important that its first page consisted of the portrait of Einstein taken by the famous Canadian photographer Yousuf Karsh. While studying this paper for my research on the motion of bodies in Einstein’s gravity theory, I discovered that there was an error in the derivation of the equations. I asked Roy to check the paper, which he did, and he agreed that there was a serious problem. We decided to write a paper together pointing out this problem. Indeed, we felt obliged to do so for the sake of posterity, alerting researchers to the fact that this famous paper was actually not correct. We submitted our paper to Physical Review, the premier physics journal in America.
To our complete dismay, several weeks later we received a letter from Peter Bergman, an editor at Physical Review and a former assistant to Einstein at the Institute for Advanced Study in Princeton. The letter stated that Physical Review could not publish our paper because it would “besmirch the reputation” of one of the greatest physicists of the twentieth century. I was so upset by this intellectual dishonesty that I contemplated leaving physics. I suffered deeply from an idealistic notion of how science should be conducted, seeking the truth and trying to understand the workings of nature. (Some might consider this youthful idealism, but more than fifty years later, I still feel the same.)
The way the leading American journal in physics treated our paper was disillusioning to me because our paper was not wrong; rather, Einstein’s reputation was considered more important than the truth. Einstein had died in 1955, so of course I was unable to correspond with him about this. I felt certain that he would not have condoned this censorship by the Physical Review.When I had first discovered the error in the paper, I had written to Leopold Infeld, who had left the University of Toronto and was then a professor in Warsaw. He never replied to my letter. I wrote again, pleading for his help, explaining that I was a student at Cambridge finishing my Ph. D., and it was important for me to know what to do about this error, which made the main arguments of the paper false, because the subject of the paper formed part of my thesis. Again, I did not receive a reply.
I often went to the weekly informal discussions held in Dennis Sciama’s rooms at Trinity, where, in addition to Sciama, Ivor Robinson, a relativity theorist who was visiting Cambridge, and Felix Pirani were sure to be present. On one such occasion, Roger Penrose was also present.
Penrose was a year or two ahead of me at Cambridge, having just finished his Ph. D. in mathematics at St. John’s College when I met him. Roger came from the well-known Penrose family. His brother, Oliver, was also a physicist, specializing in condensed matter physics.
When I first made his acquaintance, Roger was deliberating whether his future should be as a mathematician or a theoretical physicist, and we discussed relativity theory. As with Roy Kerr, I suggested to Roger, as did Sciama and Robinson, that he apply his brilliant talent for mathematics to Einstein’s gravitation theory. We emphasized to Roger that there was a great need in relativity theory for solutions of mathematical problems in the theory. The physics problems, demanding research in particle physics and quantum field theory, already constituted an active program at Cambridge, spearheaded by Abdus Salam and Paul Matthews.
Penrose was a quiet young man of slight build, with a shock of black hair and a pale, studious face. He appeared to be of a calm disposition and spoke with a soft, upper-class-English voice. Roger took to heart our suggestions about future research on gravitation theory, and as time eventually showed, he did seminal work in relativity theory; for example, inventing the celebrated conformal Pen-rose diagrams, which had a significant application in black hole physics. In 1965, he published a paper in Physical Review Letters, “Gravitational Collapse and Space-Time Singularities,” formulating a rigorous theorem about the necessity for an essential singularity occurring at the centre of the Schwarzschild black hole solution of Einstein’s field equations. This singularity was associated with the event horizon that formed when a too-massive star collapses under its own gravitational attraction and becomes a black hole. This is a mysterious solution of Einstein’s field equations, which began to come into prominence with the work of John Wheeler and his students at Princeton. Later, Penrose collaborated with Stephen Hawking in proving that, given certain assumptions in Einstein’s general relativity, a singularity at the time of the Big Bang was inevitable. These published papers were partly responsible for a revival of interest in Einstein’s gravitation theory in the late 1960s and 1970s.
While I was busy working towards my Ph. D.,my mother and father were not doing well in Denmark. My father was still suffering the effects of TB, and my aging mother was working long hours on her feet in restaurants. When Mr. Sanderson, of the Nuffield Foundation in London, heard of my parents’ plight, he decided to help out by bringing them to Cambridge. With improved health, he believed my father would find it easier to locate work, which was scarce in Copenhagen at that time, especially for foreigners. He also felt that the stress of worrying about my parents would adversely affect my doctoral research.
My parents arrived in England in 1956, and I first found rooms for them to rent in a house in Cambridge, and then a comfortable house on Oxford Road not far from the colleges. I moved in with them, which proved to be a great help to me, for my mother was able to feed me and keep my clothes laundered so that I could concentrate fully on my research and on my girlfriend, Bridget, who had a room above the George and Dragon Pub in Cambridge.
*The nineteenth-century French astronomer Le Verrier discovered that the planet Mercury’s orbit did not agree with the predictions of Newtonian gravity. The perihelion, or position of the planet’s orbit closest to the sun, advanced over time to form a rosette pattern. Le Verrier concluded that a new planet must be responsible for this gravitational anomaly, and must lie between Mercury and the sun. He christened the undetected planet “Vulcan.” But in 1915, Einstein calculated the perihelion advance of Mercury using his equations of general relativity and found it agreed accurately with over a century’s observational data, without any need for a new planet. The reason for the anomaly in Mercury’s orbit turned out to be the warping of spacetime near the sun, Einstein’s new concept of gravity.
*Riemannian geometry is a non-Euclidian geometry developed in the nineteenth century by Georg Bernhard Riemann that describes curved surfaces on which parallel lines can converge, diverge and intersect. Einstein made Riemannian geometry the mathematical formalism of general relativity.