Higgs force: The symmetry-breaking force that makes the world an interesting place

Nicholas Mee

Higgs Force traces the history of the human quest for understanding how the Universe works, starting from the atomic ideas of the ancient Greeks and finishing with the launch of the Large Hadron Collider at CERN. It is a remarkable fact that the author was able to present it as a continuous story, tracing the analogies between the earliest ideas of elements (fire-air-water-earth) and the accepted current theory of elementary particles. The description of this theory, which has become known as the standard model, culminates in the story of the search for the Higgs boson, which gives the book its title.

The standard model states that the world is made out of a just few types of elementary particles. For example, all atoms consist of three such varieties — electrons, up-quarks and down-quarks (the last two form a nucleus). The job of other particles — gluons and photons — is to hold the atom together, mediating the forces of attraction. A few more particle types do not feature prominently in the readily observable substances, but show up as results of various particle collisions and transformations.

Quite apart from this happy particle stew stands the one remaining constituent of the standard model — a particle called the Higgs boson. It is the only unconfirmed component of a generally very successful theory of the world — the Higgs boson has not yet been observed, even once. This circumstance alone would not explain the amount of scientific interest and the gigantic international efforts to find the Higgs boson. The extra motivation comes from the structure of the standard model. It is such that, should it turn out that the Higgs boson does not exist, the entire theory will stop making sense. For example, this particle is essential for understanding the reason why atomic particles have mass.

The author draws attention to the repeating pattern in the progress of science. Over the course of the investigation, the number of known elementary building blocks of the Universe has increased. Human nature, however, dictates that the true, beautiful theory of the universe should include only a small number of building blocks. If you have not three or four but tens or hundreds of them, it must mean that your building blocks are not elementary after all, and their abundance is explained by the fact that they are combinations of a small number of true building blocks.

This explanation comes from noticing a certain pattern. When the number of known chemical elements became uncomfortably large, a regular pattern was observed in them (the periodic table), and this eventually led to the discovery that all these elements are nothing but combinations of just three elementary particles — electrons, protons and neutrons. Then history repeated itself. It was discovered that, in addition to these three, there are many more elementary particles, leading to the idea that these particles are not elementary after all, and we should look for their building blocks, which were found to be quarks. In fact, the modern standard model already contains a rather large number of particles, making many physicists think that perhaps we are at the beginning of yet another such cycle. The author mentions this idea when describing string theory at the end of Chapter nine.

The book is split into nine chapters. The first chapter describes the early stages of physics and chemistry — roughly up to the discovery of the periodic table of chemical elements — and introduces the all-important idea of symmetry. Chapter 2 concerns the idea of unification — the story of discovering that seemingly diverse phenomena (such as electrostatic and magnetic forces) are different manifestations of the same phenomenon. Each such discovery was a great (if temporary) simplification of the known world, fuelling the idea that the finding of the few true elements is imminent. The current understanding, for example, is that there exist only three fundamental interactions in our Universe. For the author's purposes there are only two, because the force of gravity is quite different from the others and does not play any role in the world of elementary particles and in this book. After a brief history of quantum theory (chapter 3), these two interactions are described in more detail in chapters 4, 5 and 6. The remaining three chapters are devoted to the ever-accelerating story of the physics of elementary particles in the second half of the 20th century and the beginning of the 21st. In particular, the topic of the final, ninth, chapter is the ongoing search for the Higgs boson. This is where the reader is left wondering whether or not the hopes of the physicists will materialise in the nearest future.

The book is written in a simple and engaging style, and the author chooses the level of complexity well for a general audience. Inexplicable transitions do occur, however. Here are a few examples. The idea of symmetry is presented in the first chapter using geometrical examples — such as the rotations of a hexagon. This will not be much help to a lay reader at the end of the second chapter, where it is mentioned that at sufficiently high temperatures there is symmetry between the weak and electromagnetic interactions. A careful reader might also wonder what temperature means in the context of elementary particles. Also, the author consistently refers to interactions as forces (except in the detailed discussion of beta-decay in chapter 5). Most of the time it is a reasonable choice of words, since the discussion of forces starts with the force of gravity, the electrostatic forces, etc. But given this introduction, how should the reader understand, for example, the words that the weak force "changes the identity of matter" and is responsible for particle transformations?

These minor shortcomings are greatly outweighed by the overall excellence of the material and presentation. Higgs Force will be of interest to anyone interested in physics, as well as to those physicists whose area of expertise is not particle physics.

Book details:

Higgs force

Nicholas Mee

paperback — 440 pages

Quantum Wave Publishing Limited (2012)

ISBN: 978-0957274617

About the author

Ilia Rushkin works for a non-profit maths education organisation in Houston, US.