The Large Hadron Collider (LHC), mankind's newest and most powerful particle accelerator, has recently begun operations. Billed as "the most ambitious scientific experiment of all time", it represents the combined effort of thousands of particle physicists worldwide and their best hope for unravelling the structure of the Universe at the smallest scales. If you have ever wondered what would drive an entire scientific community to spend 20 years designing a single experimental facility, or are merely curious as to what makes particle physics so fascinating and seductive, then this book is for you. The author, a theoretical particle physicist, has written this overview for the interested general public, with its publication timed to coincide with the first LHC data.
The first of three sections describes the history of fundamental particle discovery, from the atom to quarks, leptons and force carriers. It culminates with the development of the Standard Model, or "Sublime Marvel" as the author whimsically terms it - the theory that describes the behaviour of all known fundamental particles. There is nothing here that hasn't been described in other texts, but the tone is conversational and entertaining, and the history is enlivened with character sketches and comments from the major players.
The LHC accelerator and its four main experiments occupy the central section of the text. These are also approached historically, starting with the development of accelerators from the era of Ernest Rutherford onwards, the race for discovery at previous particle physics accelerators worldwide, culminating with a description of the LHC itself. Admittedly, the dizzying array of mind-blowing facts interspersed in the description can get rather irritating at times. The four experiments - Alice, Atlas, CMS and LHCb - occupy a separate chapter at the end of the section. Atlas and CMS are described in detail, and the chapter includes an interesting discussion of the civil engineering and logistical challenges inherent in assembling gigantic pieces of precision equipment 100m below the Earth's surface. The Alice and LHCb experiments, although no less interesting, are summarised rather briefly at the end.
The final and longest section of the book describes the theories that the LHC has been built to test. Symmetry and naturalness, two important guiding principles in theoretical particle physics, are discussed and their importance in framing a successful theory of the Universe explained. This leads to a discussion of alternative theories of particle physics that may provide a better description of the Universe - supersymmetry, extra dimensions, string theory - as well as a description of loose ends including gravity, dark matter and dark energy that simply do not fit in the Standard Model. The author takes no hostages in this section. The concepts are hard, but he provides some fantastic insights, as well as refreshing descriptions of the parts of the theory that really annoy theorists ("The Higgs is like the toilet of the Standard Model edifice"). Reading this is like being led through the wonderland of theoretical physicists' most fervent imaginings by a slightly wicked, gossipy guide. Readers with a limited background in maths and physics will need to persevere to picture many of the details and may struggle with some of the ideas. But for those readers who have some background, and even for experts, the insights offered here make A Zeptospace Odyssey immensely valuable.
Should you read this book? You can find equally good descriptions of the historical development of particle physics elsewhere, and plenty of information about the LHC online, but this book's insights into the most fundamental theories of the Universe are wonderful. If you have any interest in what's happening at the frontiers of our understanding of the Universe, then it's a must.
A Zeptospace Odyssey: A Journey into the Physics of the LHC
By Gian Francesco Giudice
Oxford University Press 288pp, £25.00
Published 3 December 2009