Particle Accelerators: From Big Bang Physics to Hadron Therapy, Ugo Amaldi, Springer, 2015. $34.99 (284 pp.). ISBN 978-3-319-08869-3 Buy at Amazon
Particle Accelerators: From Big Bang Physics to Hadron Therapy takes us on a fascinating odyssey of accelerator history and applications. Author and prominent CERN scientist Ugo Amaldi’s principal aim is to highlight and praise the role of the machine builders. In doing so, he borrows a comparison made by particle theorist Victor Weisskopf, CERN director general from 1961 to 1965. Weisskopf likens accelerator builders to the creators and captains of the ships that brought Christopher Columbus and his crew to the Americas; experimentalists to those who set foot on the new lands and described them; and, somewhat self-mockingly, theorists to those who stayed behind in Europe and made the prediction that Columbus would arrive at India. Amaldi’s book also confirms the view that developments in science are driven by the achievements of many people across many generations, and that we are indeed standing on the shoulders of giants.
The first version of Particle Accelerators was published in 2012 and written in Italian. In 2013 it won a science communication award from the Italian Book Association. Following that success, the author considerably expanded his text, adding many useful details. In its present form, the book contains many recollections of CERN; it would definitely warm the heart of anyone who worked and lived in that wonderful scientific mecca.
Particle Accelerators, which is aimed at the general public, is filled with intriguing analogies, metaphors, and humor. For example, the author describes the uncertainty principle as the process of taking a “loan of energy” from the “Heisenberg bank,” with the unusual twist that the greater the loan amount, the earlier it matures. He compares the Bevatron at Lawrence Berkeley National Laboratory to a 10 000-ton “cracker of invisible nuts” and electron–positron annihilation to the disappearance of two colliding strawberries giving rise to a flood of bananas or apples. And he suggests what he considers a compact and more meaningful nomenclature for the three neutrinos: neutrino for the electron neutrino, neutretto for the muon neutrino, and neutrotto (or fatter neutrino) for the tau neutrino.
After telling the story of the early accelerator builders, the book goes on to particle physics, the field that has most benefited from the technology. Topics covered include the standard model and its extensions; dark matter; dark energy; supersymmetry; and string theory, which the author believes provides the most likely explanation for symmetry breaking. If a subsequent edition is written, I hope it includes brief and simple descriptions of the many phenomena and methods that are mentioned but never explained—for example, synchrotron radiation and the supernova standard candles that led to the idea of an accelerating universe.
Medical applications are featured in the book’s concluding section, which describes in popular terms the basics of x-ray and particle imaging and tumor treatment. Readers will learn about many technical details and enjoy some intriguing stories along the way. For instance, the first—and for a long time, the only—interest in an early article outlining computerized tomography came from a Swiss center for avalanche research, which wanted to use the technology to find objects—like lost skiers—trapped in snow.
Amaldi captures the romantic spirit of the early days of particle physics experiments. He also touches on the cooperation and competition between the continents. Surprisingly, at least at the time this edition was published, all bosons since 1948 had been discovered in Europe and all fermions in America—a peculiar sort of symmetry breaking.
The author also occasionally makes what some readers may consider as frank and provocative remarks. For example, he states that the Large Electron–Positron Collider could have discovered the Higgs more than a decade ago had he and his colleagues convinced the CERN directorate to invest substantially in upgrading the superconducting RF cavities. Amaldi also laments that Bruno Touschek and Gersh Budker were not rewarded with the Nobel Prize for their role in the development of electron–positron colliders; he suggests that had the scientists been working in the US—where the main action was—they would have received the honor. In any case, such comments are nicely balanced by wonderful stories of cooperation, such as between Brookhaven National Laboratory and CERN during the building of the CERN Proton Synchrotron.
Particle Accelerators culminates with an inspiring story of the development and creation of the Italian National Center for Oncological Hadron Therapy, a great achievement for Amaldi, who put an enormous amount of effort and energy into its creation. He is now working to develop a novel linac for proton therapy. These initiatives prove the author’s own maxim that “physics is beautiful and useful.”
Andrei Seryi is director of the UK’s John Adams Institute for Accelerator Science and professor of physics at the University of Oxford. He is author of Unifying Physics of Accelerators, Lasers, and Plasma (CRC Press, 2015).
