After big milestone, the quest will go on

Momentous as Wednesday’s announcement of the discovery of a new sub-atomic particle at the CERN laboratories near Geneva was, it’s not the end of the quest to understand the universe. Yes, it’s a triumph of science and of international collaboration, but in the end only “a milestone”, not the end of the journey, as a CERN scientist put it.

Physicists have looked for the Higgs Boson for nearly 50 years, and what they found looks like Higgs Boson. But is it? In what might be an anti-climax of sorts for the layman, fed the misleading idea that its discovery would be the ultimate discovery and explain everything in the universe, scientists are now taking great pains to explain that its discovery is only the beginning of years of analyses, experimentation, verification and theorising.
For one, while scientists know the mass of the new particle, they don’t yet know anything else about it — what charge does it carry, if any? Is it a fundamental particle (like the electron), or is it itself a composite of other particles? Does it come in only one “flavour” or in many? For another, as scientists try to understand these properties, they will also begin to confirm or reject, with greater certainty than before, theories on the fundamental structure of matter and constitution of the universe.
If the new particle does indeed turn out to be Higgs Boson — a fundamental particle with no further constituents, and single-flavoured to boot, then all it might really do is confirm the validity of the standard model of physics, the best explanatory model of the fundamental structure of matter we have today. But it will leave physicists no wiser in terms of solving mysteries that are beyond its explanatory capacity, such as dark matter, supersymmetry, extra dimensions. That’s a prospect that many scientists dread. If, on the other hand, scientists find that Higgs Boson is itself made of more fundamental particles, and therefore potentially comes in different flavours, then the discovery at CERN will not only confirm the standard model but will also open up exciting new science. Like supersymmetry — the theory that all four fundamental forces of nature (strong nuclear force, weak nuclear force, electromagnetic force, gravitation) were bound together at the instant of the universe’s creation, and then broke up.
The multi-billion-dollar Large Hadron Collider may be the Taj Mahal of modern physics, and its experiments among the grandest ever planned, but it was never built for the love of just one theory. It was built to explore the universe much beyond the standard model. Hundreds of theoretical physicists around the world, not least in India, are already embarked on this. It’s a quest that never ends.