All of the predictions based on these ideas have turned out to be in accord with experiment. But there was one major thing missing: What about the invisible field? How could we tell if it really exists? It turns out that in particle physics, for every field in nature, like the electromagnetic field, there must exist an elementary particle that can be produced if one has sufficient energy to create it. So, the background field, known as a Higgs field, must be associated with a Higgs particle.
In the 1990s in the United States, a gigantic machine called the Superconducting Super Collider was being built (involving the largest tunnel ever dug—some 60 miles in circumference) to search for the Higgs—and the origin of mass. But Congress, in its infinite wisdom (Congress seems to have gotten no wiser since), decided that the country couldn’t afford the $5 billion to $10 billion that had already been approved by three different presidents. Back then, $5 billion was a lot of money! So, the LHC was constructed in Geneva by a group of European countries, and the rest is history, or will be.
The discovery announced today in Geneva represents a quantum leap (literally) in our understanding of nature at its fundamental scale, and the culmination of a half-century of dedicated work by tens of thousands of scientists using technology that has been invented for the task, and it should be celebrated on these accounts alone.
But I find it particularly exciting for two reasons—one scientific, the other more personal. First, the standard model, as remarkably successful as it has been, leaves open more questions than it answers. What causes the Higgs field to exist throughout space today? Are there other forces that dynamically determine its configuration? Why doesn’t the same phenomenon that causes the Higgs particle to exist at the mass it does cause gravity and the other forces in nature to behave similarly? Over the past 40 years or so, a host of theoretical speculations have been developed to answer these questions. But like those who are sensorially deprived, we may just be hallucinating. The cold water of experiment may now wash away many of our wrong ideas and, perhaps more importantly, could point us in the right direction. In the process I expect what we will discover about the universe may currently be beyond our wildest dreams.
More than this, however, the Higgs field implies that otherwise seemingly empty space is much richer and weirder than we could have imagined even a century ago, and in fact that we cannot understand our own existence without understanding “emptiness” better. Readers of mine will know that as a physicist, I have been particularly interested in “nothing” in all of its forms and its relation to something—namely us. The discovery of the Higgs says that “nothing” is getting ever more interesting.