Science, Head of the Theoretical Physics Division at the Rutherford Appleton Laboratory and Head of Communications and Public Education at CERN. He is the winner of the Kelvin Medal of the Institute of Physics for his "outstanding contributions to the public
understanding of physics." . His latest book is Half Life, a scientific biography of nuclear scientist (and possible spy) Bruno Pontecorvo.
I always wanted to know: why? Decades later I discovered that science deals with 'how?', but by then I was hooked. Chemistry at school consisted of lots of facts, too many to remember, but it was the chemistry teacher who told me that everything is made of atoms, which in turn are all made of electrons encircling a nucleus, and the only difference between one atomic element and the next is the number of protons. That such simplicity could lead to such richness astonished me then, and still does. It also gave me the hope that I could derive all of chemistry from this basic fact (a hope unfulfilled) and pointed me towards physics, eventually particle physics. I always loved numbers, and algebra, and was useless with experiments. That’s how I became a theoretical physicist. I still find it remarkable that by scribbling equations on pieces of paper, it is possible to deduce profound consequences about the nature of the universe, which experiments subsequently confirm. How can mathematics 'know' reality before we ourselves?
Why this book?
I wrote a book called Neutrino, the story of Ray Davis’ heroic forty year quest to detect these ghostly particles, which theory implied must be pouring from the sun in vast quantities. He survived long enough to collect a Nobel Prize, in 2002, at age 87. In the course of researching that book, I discovered that behind the scenes another physicist, Bruno Pontecorvo, had played a central role. However, halfway through his life he had defected to the Soviet Union at the height of the cold war, and missed out on one Nobel Prize as a result (he was unable to share in Davis’ Nobel, later, as Pontecorvo died in 1993). I began to research Pontecorvo’s life, and the question of why he had made the fateful flight to the USSR began to take centre stage. In addition to being a great physicist, had he also been a spy, as some conjectured? I discovered that he had lived in my home-town, and I found people who had known him, sixty-five years ago. I traced school-friends of his son, who had been twelve years old at the time, and they told me their memories of the disappearance. Then we discovered that one of the teachers at their school had worked for MI5, and suddenly I realised that I had an inside track to a spy mystery as well as a scientific biography. I met family members of two certain atomic spies, as well as several of Bruno Pontecorvo’s own relatives, along with others from the world of smoke and mirrors. My breakthrough was in unearthing an MI5 document that had been lost – or maybe 'lost' – which revealed that the infamous Kim Philby had played a central role in Pontecorvo’s disappearance. From which point, Half Life wrote itself. I am flattered that, having spent forty years as a physicist, reviewers are now describing me as an “historian”.
I am writing a short book about my fascination with solar eclipses, which began as an eight years old schoolboy and, since I was present at a total solar eclipse in 1999, have become an obsession. In my new guise as 'historian' of scientific affairs, I am researching another atomic physics espionage mystery from the Second World War. This has grown out of my research into Half Life, which revealed some previously unknown facts about Klaus Fuchs, his mentor Rudolf Peierls – the British father of the atomic bomb - and the role of MI5 and the FBI. But as there may be literary spies out there, I shall say no more for now!
What’s exciting you right now?
In my own field of particle physics, I am eagerly awaiting the re-start of the Large Hadron Collider at higher energies. Having discovered the Higgs boson, will the LHC find evidence for supersymmetry, or reveal the dark matter particles, which, according to cosmologists, are more copious than the stuff that we presently know? Only Nature knows the answers so far, but the weird property of mathematics, which I mentioned at the start, suggests that discoveries are waiting to be made. Outside particle physics, I am intrigued about consciousness: how many atoms are needed to gather together before they are self-aware? Unfortunately I have no idea how to answer this question. Other than that, I hope that answers will come to some of these questions while I am still capable of sharing my excitement about them, and their significance, in print sometime in the future.