me to this place. In my peripatetic and traumatic childhood in Denmark, England and Scotland during and after the Second World War, I showed little aptitude for mathematics and science—so little, in fact, that I was not even allowed to enter university. Instead, I set my sights on becoming an abstract painter, an almost impossible career choice in the immediate postwar years. But then something peculiar happened to me to change drastically the course of my life. Within little more than a year, I vaulted from working at odd jobs in Copenhagen—window cleaner, delivery boy, mail sorter—to entering the Ph.D. program in physics at Trinity College, Cambridge.
How did this happen? What did it mean? Colleagues as well as my family have often encouraged me to write about my early life and the unusual way that I entered physics—and to put down on paper the many anecdotes with which I had regaled them, about the famous physicists of the twentieth century that I had the good fortune to meet. When I ask myself how I became a physicist in the first place, and how I managed to remain outside the box of conventional physics, working on truly fundamental questions of nature throughout so much of my career, my thoughts keep returning to the difficulties of my childhood, the love of beauty that inspired my first career as an artist and the influence of those giants of physics, whose kindness and help encouraged me on my way.
Physicists explore the nature of the universe, from its farthest edges to the smallest constituents of matter. In the twentieth century, with amazing improvements in telescopes and many space missions, we were able to expand our understanding of the evolution of the universe back almost to its beginning. This is a remarkable development in the history of science, because from the Greeks up until the beginning of the twentieth century, our astrophysical investigations were restricted to the much smaller universe of our solar system and our galaxy. We have also made great strides in penetrating the universe of the very small, and gradually the mysteries of the structure of matter are being revealed to us. Cracking the quantum code of matter is only possible through extraordinarily high-energy accelerators such as the Large Hadron Collider (LHC) at the largest particle physics laboratory in the world, at CERN (European Organization for Nuclear Research), near Geneva, which began operation in 2010. We are on the threshold of exciting new discoveries in the realm of particle physics, which will help unravel the mysteries of the nature of matter.
Theoretical physicists attempt to build models of nature based on mathematics, and experimental physicists provide the data that can test the ideas and models proposed by the theoretical physicists. In practice there is an interplay between theory and experiment. Often, successful research in theoretical physics starts with a well-grounded knowledge of experimental data, building up from this data into a theory. Another important area of physics is industrial physics, where developing new technologies eventually leads to advances in computers, televisions, cellphones, medical diagnostics and many other electronic applications. All of these devices grew out of abstract theoretical ideas and their subsequent verification by experimental physics.
From the beginning of my studies, I wanted to become a theoretical physicist. I was fascinated by the intellectual adventure of trying to figure out how the universe worked, using its language of mathematics. I was attracted to the double-edged approach that theoretical physicists must take, combining a dreamer’s awe of nature’s inner workings with the rigour of having to verify one’s ideas and models of nature with data, whether from telescopes or particle colliders. I also felt more comfortable working mainly on my own, as most theoretical physicists do, than working in the large teams that constitute so much of contemporary experimental physics.
To me, the only physics worth doing is outside-the-box, non-mainstream physics, for that is how our understanding of nature moves forward. Of course, I have, like most other physicists, spent time in my career working out the details of someone else’s theory, calculating the consequences of someone else’s ideas. But that, to me, is not exciting and groundbreaking work. Niels Bohr, Albert Einstein, Erwin Schrödinger, Paul Dirac and others described in this memoir all worked on non-mainstream physics as a matter of course. They all broke through the boundaries of what constituted the conventional paradigm in physics in their day. Perhaps my interactions with them as a young student steered me in this direction of always aiming to do the kind of physics that challenges the conventional wisdom.
Albert Einstein, in particular—and the letters we exchanged over several months—opened the doors for me into the academic world. Einstein was always an iconoclastic physicist, and his revolutionary ideas were not immediately accepted by the physics community. Indeed, in some cases, such as his interpretation of light as photon particles, it took several years before his ideas were incorporated into mainstream physics, and became part of the early revolutionary development of quantum mechanics.
From the very beginning of my research career as a student at Trinity College, Cambridge, in the early 1950s, I attempted, like Einstein, Paul Dirac, Werner Heisenberg and other well-known twentieth-century physicists, to get at the heart of the fundamental issues in physics. In my first three papers, published while I was a student, I devoted myself to modifying Einstein’s gravity theory. In this effort I was actually following in Einstein’s footsteps, for after developing his great theory of gravity, general relativity, in 1915, he sought a unified field theory of gravity and electromagnetism, which necessitated modifying general relativity.
I always say that to achieve success in fundamental, theoretical physics, one must be childishly optimistic, possess a thick skin and live a long life. This memoir is an attempt to trace the origins of the desire to work on non-mainstream, fundamental science in my own life. I hope that this narrative will entertain you, that you will enjoy this journey into the company of the giants of modern physics who were my mentors.
MY PARENTS MARRIED three weeks after they met, speaking barely a word of each other’s language. My father, George Moffat, was born in 1907 in Glasgow, Scotland. As he grew up there, he played musical instruments from a young age, beginning with a classical-piano teacher who had been a pupil of Franz Liszt. My father also took up the trumpet in the Scottish Boys’ Brigade, won the all-Scotland championship in coronet playing and taught himself to play the accordion. In addition to his musical talents, he was a successful artist, and at age seventeen won a scholarship to go to Rome to study painting. His father forbade him to go, however, for he wanted my father to work in his tailoring business in Glasgow. But my father left home and joined a band in England, playing the trumpet. The band toured around Europe just before the Second World War and ended up at the La Scala nightclub in Copenhagen, where my mother, Esther Winther, a local girl, was working as a chorus dancer. They immediately fell into a heady romance.
My mother learned that she was pregnant while my father was touring with his band in Norway. Her gynecologist was very surprised that she had become pregnant, for she suffered from a serious condition that he had told her would prevent her from ever having a child. Throughout her life, my mother always spoke of her pregnancy and my birth as a miracle. She never became pregnant again.
In 1938, when I was six, my father foresaw that the Nazis would invade Denmark. Since he was still an alien, a British citizen holding a British passport, the Nazis would have detained all three of us and put us in a camp. So we moved to Britain and, my parents believed, to greater safety.
When war broke out in September 1939, the entertainment industry in England closed overnight because of the widespread fear that the Germans would bomb London. My father took a job as a truck driver for a pharmaceutical company, which was dangerous work, driving around London at night in the blackouts. He then worked in the intelligence service, starting by censoring servicemen’s letters from abroad.
Concerned for my safety, given the ominous signs of the coming bombings, in late 1939, when I was seven years old, my parents evacuated me from London, putting me
