Researchers tell of ‘God particle’

AP

LAID BARE: An artists impression of how a Higgs boson may function. Picture: AP

John Heilprin

Sapa-AP

GENEVA:

Scientists believe the “God particle” that may explain the underpinnings of the universe is real, and they are about to present their evidence to the world.

Physicists at the world’s biggest atom smasher plan to announce tomorrow that they have nearly confirmed the primary plank of a theory that could shape the scientific understanding of all matter.

The idea is much like gravity and Isaac Newton’s discovery: it was there all the time before Newton explained it. But now scientists know what it is and can put that know-ledge to further use.

The focus of the excitement is the Higgs boson, a subatomic particle that, if confirmed, could help explain why matter has mass, which combines with gravity to give an object weight.

Researchers at the European Organisation for Nuclear Research (Cern) say that they have compiled vast amounts of data that show the footprint and shadow of the particle – all but proving it exists, even though it has never actually been glimpsed.

But two independent teams of physicists are cautious after decades of work and billions of dollars spent. They don’t plan to use the word “discovery”.

They say they will come as close as possible to a “eureka” announcement without uttering a pronouncement from the scientific mountaintop.

“I agree that any reasonable outside observer would say, ‘It looks like a discovery’,” said British theoretical physicist John Ellis, a professor at King’s College London who has worked at Cern since the 1970s. “We’ve discovered something which is consistent with being a Higgs.”

Cern’s atom smasher, the $10 billion (R80 billion) Large Hadron Collider on the Swiss-French border, has been creating high-energy collisions of protons to investigate dark matter, antimatter and the creation of the universe, which many theorise occurred in a massive explosion known as the Big Bang.

The phrase “God particle,” coined by Nobel Prize-winning physicist Leon Lederman, is used by laymen, not physicists, more as an explanation for how the subatomic universe works than how it all started.

Rob Roser, who leads the search for the Higgs boson at the Fermilab in Chicago, said: “Particle physicists have a very high standard for what it takes to be a discovery.”

Roser compared the results that scientists will announce tomorrow to finding the fossilised imprint of a dinosaur: “You see the footprints and the shadow of the object, but you don’t actually see it.”

Fermilab, whose competing atom smasher reported its final results yesterday after shutting down last year, said its data did not settle the question of the Higgs boson, but it came tantalisingly close.

“It’s a real cliffhanger,” said Gregorio Bernardi, a physicist at the University of Paris who helped lead one of the main experiments at Fermilab.

He cited “strong indications of the production and decay of Higgs bosons” in some of their observations.

Fermilab theorist Joseph Lykken said the Higgs boson “gets at the centre, for some physicists, of why the universe is here in the first place”.

Though an impenetrable concept to many, the Higgs boson has until now been just that – a concept intended to explain a riddle.

How were subatomic particles, such as electrons, protons and neutrons, themselves formed? What gives them their mass?

The answer came in a theory first proposed by Scottish physicist Peter Higgs and others in the 1960s. It envisioned an energy field where particles interacted with a key particle, the Higgs boson.

The idea is that other particles attract Higgs bosons and the more they attract, the bigger their mass will be. Some liken the effect to a ubiquitous Higgs snowfield that affects other particles travelling through it depending on whether they are wearing, metaphorically speaking, skis, snowshoes or just shoes.

Officially, Cern is presenting its evidence this week at a physics conference in Australia, but plans to accompany the announcement with meetings in Geneva. The two teams, Atlas and CMS, then plan to publicly unveil more data on the Higgs boson in October and December.

With two independent experiments showing there's less than a one in 16 000 chance of being wrong, it’s a matter of how their work is put together.