By Jim Baggott
On 4 July scientists at CERN in Geneva declared that they had discovered a new particle ‘consistent’ with the long-sought Higgs boson, also known as the ‘God particle’. Although further research is required to characterize the new particle fully, there can be no doubt that an important milestone in our understanding of the material world and of the evolution of the early universe has just been reached.
Exciting times! But why all the fuss? What is the Higgs boson and why does it matter so much? Was finding it really worth all the effort?
The Higgs boson is important because it implies the existence of a Higgs field, an otherwise invisible force field which pervades the entire universe. Unlike other kinds of force field (such as a gravitational field) it points, but it doesn’t push or pull. It was invented in 1964 in attempts to explain how otherwise massless particles could acquire mass.
The mechanism works like this: Without the Higgs field, elementary particles such as quarks and electrons would flit past each other at the speed of light, like ghostly will-o’-the-wisps. The elementary particles that make up you, me, and the visible universe would consequently have no mass. Without the Higgs field mass couldn’t be constructed and nothing could be.
What actually happens is that these elementary particles interact with the Higgs field and are slowed down by it, as though swimming in molasses. We interpret this ‘slowing down’ as inertia and, ever since Galileo, we have identified inertia as a property of things with mass.
Many of the predicted consequences of the Higgs field were borne out in particle collider experiments in the early 1980s. But inferring the field is not the same as detecting its tell-tale field particle. On 3 July we had hypotheses and compelling theoretical structures. The following day we began to gather hard scientific facts. Our understanding took a giant leap forward.
The publication of Higgs: The Invention and Discovery of the ‘God Particle’ is timely, coming only six weeks after the announcement. But I had the idea for a book about the discovery of the Higgs boson in March 2010, just as CERN’s Large Hadron Collider was setting a new world record for particle collision energy. This is perhaps the first example of a book that has been largely written in anticipation of a discovery.
Precisely what kind of boson has been discovered remains to be seen, and there’s hope of more surprises yet to come.
Jim Baggott is author of Higgs: The Invention and Discovery of the ‘God Particle’ and a freelance science writer. He was a lecturer in chemistry at the University of Reading but left to pursue a business career, where he first worked with Shell International Petroleum Company and then as an independent business consultant and trainer. His many books include Atomic: The First War of Physics (Icon, 2009), Beyond Measure: Modern Physics, Philosophy and the Meaning of Quantum Theory (OUP, 2003), A Beginner’s Guide to Reality (Penguin, 2005), and A Quantum Story: A History in 40 Moments (OUP, 2010).