The discovery of the Higgs boson is a massive achievement — let's just savour it.
It is the kind of breakthrough that comes along once in a generation: scientists have found a long-sought particle. The news comes from CERN, Europe's high-energy physics lab near Geneva, Switzerland, and it quickly travelled around the world. As described on page 147, the particle is almost certainly the Higgs boson, part of the mechanism that endows other fundamental particles with mass.
Outside the field, the announcement has sparked questions about the utility of particle physics and the cost of such experiments. Within it, physicists are anxious about what to do next. But now is not the time for such questions. At this moment, just for a while, we should lean back in our chairs, prop up our feet and savour the achievement.
First predicted almost 50 years ago, the boson and its corresponding field are the final pieces of one of the most successful physical theories in history. The theory has been given the perfunctory name of 'standard model', but there is nothing standard about it. Its breadth is astonishing — it encompasses all 16 (and now perhaps 17) of nature's fundamental particles, and every fundamental force apart from gravity. And as amazing as its scope is the theory's precision. It predicts the electromagnetic moment of the electron to 12 decimal places, for example, and it has verified hundreds of complex measurements made by experimental physicists over decades. So far, at least, the Higgs boson conforms well to the model's predictions, although there are intriguing hints that this could change as additional data are gathered.
No less incredible than the standard model is the effort that has been made towards its verification. Over the decades since the model was first put together, thousands of physicists have devoted their careers to it. They began with accelerators in university basements and have concluded at a 27-kilometre behemoth known as the Large Hadron Collider (LHC). Although undeniably European in character, the LHC and its four building-sized detectors are a global experiment, built by researchers and engineers from around the world. Like the theory they are helping to verify, the experimental apparatuses are pinnacle achievements — successful global collaborations unlike anything science has seen before, and very good models of how global scientific experiments should look in the future.
Everybody else grasped the significance of the moment, even if they didn't grasp the theory behind it. Praise and enthusiasm came from all corners: even the blustering tabloids and cable news stations briefly diverted from their reports of the week's banking scandals to herald the announcement.
But perhaps inevitably, questions were being raised even before the press conference to announce the discovery had come to an end. What is the Higgs good for? Was it worth all the trouble? And now that it has been found, what are physicists supposed to do?
In brief, the answers are: nothing; yes; and pop some champagne. Like great works of art, the discovery of the Higgs and the verification of the standard model are aesthetic achievements of humanity that deserve celebration. Governments might clamour for return on investment in science, but the Higgs discovery reminds us of the things that basic research is really about: curiosity, creativity and hard work. The particle needs no further justification, although with time, it could earn one, just as other great discoveries have in the past.
Sooner or later, the celebrations will end, and high-energy physicists will turn their attention to what to do next. It is not an easy time to face such an existential question: the global financial crisis means that money is tight, and without some fresh hints from the LHC, theorists will struggle to develop a framework that can exceed the standard model's exceptional power.
Some obvious lines of enquiry remain, however. Gravity, for example, continues to defy theoretical efforts to unify it with the other fundamental forces. And cosmological measurements suggest the existence of more things in heaven than are dreamt of in the standard model's philosophy — dark matter, which makes up 80% of the known matter, and dark energy, which could have an even larger contribution to the Universe.
These are tricky questions, but the fact that they even exist should give hope to the next generation of physicists and to science-lovers everywhere.