The modern synthesis of particle physics can explain how all this happened 13.7 billion years ago and how the same laws control the behaviour of matter today. Unfortunately, these esoteric secrets are known to but a few initiates, the High Priests of Particle Physics. They are hidden behind a veil of abstract and subtle mathematics. But, we will be drawing back the veil and revealing the secrets of the universe to anyone who cares to take a look.
The book is divided into three parts. The first three chapters provide the broad historical and philosophical context. The next three describe, in turn, each of the forces that are important in particle physics. The final three chapters are about the modern synthesis of the particles and forces and the search for the last missing piece in the particle physics jigsaw.
Chapter 1 is about symmetry, what we mean by symmetry and why symmetry is important in describing the world around us. We will see that whenever we find symmetries in the laws of nature, it is often a clue to a deeper hidden order within the structure of matter. And this leads into chapter 2, which is about the idea of unification. Often a multitude of different phenomena have the same root cause. More specifically, several times in the history of physics, physicists have found that what appear to be several different forces can best be described by a single unified force. We now know that there are just three different forces that play a role in particle physics and the goal of physicists is to reduce this number even further. Chapter 3 is about the crazy world of quantum mechanics, where particles behave like waves and waves behave like particles. It is all very strange, but this is what we find when we look at the structure of the atom. Quantum mechanics challenges our preconceptions of how the universe operates at its most intimate level.
The next three chapters describe the three fundamental forces. Chapter 4 is about the force that binds atoms together and controls chemical reactions. It is also the force that is powering this laptop – electromagnetism. Modern theories of particle physics are not just vague ideas, they agree with experimental measurements to an extraordinary precision. In this chapter we will see just how incredible the match between theory and reality is. Chapter 5 is about the force that causes the transmutation of the elements within the stars. Without this force, known to physicists as the weak force, there would be no complex matter, no Earth and no people, the universe would consist of hydrogen atoms and nothing more. We are composed of the ash from the nuclear furnace at the heart of a star and the stardust that was dispersed throughout the heavens in a supernova explosion; ashes to ashes and dust to dust. In chapter 6 we will see that although the universe looks very complicated and chaotic, it is constructed from very simple laws. This chapter is about quarks and the force that binds them together into protons and neutrons, and ultimately holds the atomic nucleus together. This is the strong or colour force.
We now come to the final part of the book. In chapter 7, we will see that although physicists have always sought the simplest and most symmetrical laws, much of this symmetry must be hidden if the universe is to evolve into a complex and interesting place. The idea of symmetry breaking allows us to unify the electromagnetic and weak forces into a single electroweak force. This implies that there is a field permeating the whole of space, which all the particles in the universe are continually wading through. This field, the Higgs field, breaks the symmetry between the forces and gives mass to most of the elementary particles. Chapter 8 draws all the strands together and we see how the modern synthesis of particle physics became established, and the conclusive experimental observations on which it is founded. We now have a table of elementary particles and the forces that bind them together. This table is complete, except for one last missing particle – the Higgs. The particle that is crucial to the modern synthesis. It is the particle that is implicated in the symmetry breaking that took place in the first moments of the universe. Chapter 9 is about CERN’s new particle accelerator, which has been designed to probe the innermost secrets of matter in the search for the Higgs. Tracking down the Higgs will represent one of the greatest achievements in the history of science. It will confirm that we have an extremely good understanding of the functioning of the universe at its most fundamental level. A new chapter will then open, as physicists seek to answer even more ambitious questions about the structure of the universe.