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It is not everyday that someone's name becomes inextricably linked with God. But it is not everyday that someone comes up with a theory that could help to unify the many disparate forces of the universe.
All the more strange, then, for the man behind the sub-atomic "God particle" to be an unassuming grandfather living in modest retirement in one of the more sedate districts of Edinburgh.
Professor Peter Higgs, 78, is a theoretical particle physicist, and it took him 20 years before he could even bring himself to call the God particle by its more scientific name - the Higgs boson. Up to that point, he preferred the more prosaic term, "scalar boson".
He still squirms when people refer to it by the deified moniker coined many years ago by a colleague. He first formulated the theory behind the sub-atomic particle named after him in the 1960s, and for almost half a century it has remained as elusive as stardust. That could all change later this year, however, when one of the world's biggest experiments is switched on deep beneath the Alpine meadows on the Franco-Swiss border, the home of the European Centre for Nuclear Research (Cern) near Geneva.
Within a 27km-long, underground ring, atom will be smashed into atom at something approaching the speed of light. The machine, called the Large Hadron Collider (LHC), is designed to produce energy levels expected to be powerful enough to shake out the elusive Higgs boson from its seemingly inescapable prison within the atomic nucleus.
The Higgs is just one of the discoveries that the LHC is expected to make. The team of physicists behind the project believes the LHC will produce a jewel box of discoveries that will light up the infinitesimally small world of sub-atomic physics.
"The actual discovery of the Higgs boson, if it happens, is only one part of the programme. There is vastly more for the machine to do," Professor Higgs said.
"I'm most excited, for instance, about the possible identification of super-symmetry particles - symmetrical particles of the particles we already know."
Super-symmetry refers to the "grand dance" of particles in the universe. We know about a dozen sub-atomic particles, with exotic names such as quark, lepton and neutrino. Yet for every kind of particle, there may a super-symmetrical partner.
The trouble is, we can only see one of the partners in each dancing couple, with the "significant others" remaining invisible.
If super-symmetry is confirmed by the LHC it will help scientists towards the ultimate goal of a unified theory for the fundamental forces of nature - in particular the force of gravity which so far lies outside the realm of the forces known at the quantum level of the sub-atomic particle.
"The reason it's exciting is that I'm interested in a unified theory of forces, in particular quantum gravity," Professor Higgs said.
Although long retired from research, he still possesses a child-like wonder of the world which we cannot see but which is so critical to some of the most important questions at the centre of our understanding of creation, the universe and the end of time.
Professor Higgs spent much of the weekend seeing the LHC for the first time, before it is sealed in preparation for the switch-on in a few months.
"The sheer scale of the detectors is overwhelming. It's far more impressive than anything you get out of photographs," he said.
The detectors in question are four huge underground instruments, some as big as a gothic cathedral, which will act as microscopes to identify a Higgs particle in the fraction of a split second it takes to make an appearance before it disappears.
Professor Higgs said he is 90 per cent certain the LHC will find his particle when it reaches its full working potential, perhaps in a year's time. If the machine does find the Higgs, it will cap an extraordinary career for the mathematician, given he first proposed the idea more than 40 years ago as a young theoretical physicist at the University of Edinburgh.
It will also solve one of the most pressing problems in science because the Higgs boson lies at the heart of matter itself. In particular it is supposed to explain why objects have mass and while some phenomena - such as light - do not.
Professor Higgs was the first to propose the theory that the reason why objects have mass is because they interact with an invisible field, now called the Higgs field. Heavier particles interact more strongly, whereas photons (light particles) do not interact at all. Without this Higgs field, everything - from proton to planet - would be as insubstantial as a light beam.
When Higgs first came up with the idea, few people took him seriously and even the then editor of a leading physics journal - who was based at Cern - thought it was too conjectural to be published.
"At the time I started this work, it was rather an unfashionable thing to be interested in, certainly on this side of the Atlantic ... my colleagues thought I was a bit of an idiot," Professor Higgs recalled.
Four decades later, Cern is in pole position in the race to be first to find the Higgs although its advantage has been eroded. The LHC should have opened three years ago but, as with all big engineering and construction projects, it was dogged by delays.
Meanwhile, another atom smasher at the Fermi Laboratory in the United States may have come close to solving the problem. Professor Higgs said the Fermi Lab scientists may have already done it, but may not yet be in a position to prove it because the critical evidence may still be locked up in data obscured by background noise.
But time is running out for the Fermi Lab as the giant, supercooled magnets at the LHC are prepared for their task.
The amount of supercooling involved is stupendous - when it is fully operational, the LHC will be the coldest place in the known universe.
The immense energies involved in making the atomic collisions happen have already generated unwelcome publicity for the LHC.
Some scientists have suggested that they may generate mini black holes, which have led others to suggest that these black holes could somehow merge to form a larger, destructive entity that could swallow up the entire earth.
"The black hole business has become rather inflated," said Professor Higgs, irritated by the suggestion that the LHC could become an unwitting doomsday machine.
"Even the theorists who are suggesting that mini-black holes are things that could be produced are not predicting black holes large enough to swallow up chunks of the universe. I think the publicity has rather got out of hand and some people have misunderstood it."
Hysteria aside, Professor Higgs seemed pleased that so many people outside the rarefied world of particle physics and cosmology are taking an interest in what will happen at Cern.
He is certain that something awesome is about to happen. .
"I'd be very puzzled if it wasn't discovered ... If you don't have something like a Higgs boson ... if it's not that, what the hell is it?
"If it's not found, I no longer understand what I think I understand," he said.
And if it is found? "I shall open a bottle of something."
SEARCH ENGINE
* Scientists are searching for sub-atomic particles using an underground accelerator called the Large Hadron Collider (LHC).
* By smashing particles together at near light-speed in the $2 billion laboratory researchers aim to simulate conditions at the time of the Big Bang 15 billion years ago.
* The machine is designed to produce energy levels powerful enough to shake out the elusive Higgs field - an invisible force which gives mass to the universe and makes life possible - as first argued by physicist Peter Higgs 40 years ago.
- INDEPENDENT
