Physics could be a breeze
Over the past six months, physicists have become excited about the discovery of a new particle, codenamed theta that appears to live longer than it should. Theta falls bang in the centre of Frank Close’s field, and next month he is due to give the review talk on the particle at a conference in Beijing. Only right now he doesn’t have a clue what he is going to say.
Strong evidence emerged to suggest a tantalising possibility that theta doesn’t exist. “Which leaves me to explain how so many scientists claim to have seen something that may not be there,” he grins. Not that he seems unduly bothered, as he breezes into his pokey office on the top floor of Exeter College, part of Oxford University. If anything, he appears delighted at the unexpected spanner in the works. Close likes his science to come with a sense of mystery and wonder, and the possibility that the pentaquark theta may be a chimera is right up his street.
“Science isn’t about finding the solutions to problems so much as asking the questions in the first place,” he says. “And it’s not always obvious what questions one ought to be asking. You can ask something so trivial that no one’s interested in the answer, or you can ask something so difficult you’ll never find an answer. The trick is to ask the question that will make a difference.” In general, these questions tend to blur the boundaries between why and how things happen. As one of the world’s leading particle physicists, Close has asked more than his fair share of the questions that have deepened our understanding of the universe in the past 30 years or so. Close was working on quarks — the basic particles of protons and neutrons — in the mid-60s, long before anyone had proved their existence. “It was luck,” he says. “I just happened to be in the right place at the right time.” Close won an award to study under Richard Dalitz at Oxford.
“He was working on the quark model and it seemed obvious to make that the focus of my own research,” says Close. In fact, Dalitz was just about the only person in the UK working on quarks and Close remembers feeling rather depressed and lonely for much of his doctorate.
After completing his thesis, Close went to Stanford University — the epicentre of quark research — and, as quark theory went mainstream, found himself at the forefront of a new strand of physics. By 1973 he was working at the world’s largest particle physics laboratory at Cern, Geneva, and two years later he was back in the UK as part of the theoretical physics team at the Rutherford Appleton lab in Harwell, near Oxford. Which is where he spent the next 25 years, winding up as head of the theoretical physics division. But in 2000, the UK’s Particle Physics and Astronomy Research Council (PPARC) pulled the plug. Close’s team was disbanded and a new one formed at Durham University in the north of England. “It was supposed to be a cost-cutting measure,” he says, “but it seemed a zero sum gain.”
“We lost a centre of knowledge and the new base at Durham doesn’t even have an experimental physics facility attached. Above all, it was a huge emotional stress being involved with making so many people redundant.” Rutherford’s loss was Oxford’s gain, and that is where he now divides his time between research and teaching undergraduates as a fellow of Exeter College.
“Some parts of the syllabus came as quite a shock,” he says. “I hadn’t studied electromagnetic theory since I was an undergraduate and there’s been a steep learning curve. Luckily I’ve had some very bright students who’ve got me up to speed.” Deconstructing his knowledge is one of Close’s stocks in trade. Long before science became popular, Close was writing articles and books and delivering lectures designed to make science accessible to mere mortals. He insists that much of the credit should go to understanding editors, but he’s always had the gift of the soundbite. In the late 70s he managed to get the solar neutrino problem on to Tomorrow’s World by dressing it up in the question: “Is the sun still shining?”; in the 1980s he managed to make readers of this paper feel they understood the importance of Carlo Rubbia’s discovery of the z particle — even if they forgot it minutes later.
The books followed in quick succession. ‘The Cosmic Onion’ provided a very erudite idiot’s guide to particles, and ‘Lucifer’s Legacy’ asks why there is anything, rather than nothing, in the universe. In 1996 he won the Kelvin Medal of the Institute of Physics for his contributions to the public understanding of physics and this year he has written ‘A Very Short Introduction to Particle Physics’, which is certain to become an essential crib for any A-level physics students.
Frank Close’s aim is to deconstruct physics, yet it is mysteries that delight him.