One of the biggest questions in science – does “the God particle” exist? – will probably be answered by the end of next year, it was claimed yesterday.
The Higgs boson, nicknamed the God particle, is theoretically responsible for mass, without which there would be no gravity and no universe.
Until now the enormous energies needed to winkle out the Higgs from the building blocks of matter have not been available.
Scientists at the world’s most powerful particle accelerator today predicted that within two years they will either find the Higgs boson or show conclusively that it does not exist.
Even the discovery that nature does not contain a Higgs particle will be a momentous event in physics. If this was shown to be true, scientists might have to abandon the “Standard Model”, the best theory so far for explaining the fundamental mechanics of the universe.
The search for the Higgs boson is taking place at the Large Hadron Collider, which fills a 27-kilometre circular tunnel 100 metres below the French-Swiss border near Geneva.
Dubbed the “Big Bang machine”, the LHC was built at a cost of around £2.6 billion to recreate conditions a fraction of a second after the birth of the universe.
The machine, weighing more than 38,000 tonnes, accelerates streams of protons – the “hearts” of atoms - close to the speed of light and smashes them into each other at unprecedented energies.
Huge detectors at four points in the tunnel use the collisions to probe deeper into the nature of reality than anyone has gone before.
One of the biggest, Atlas, engages some 3,000 scientists from 38 countries, including 300 from the UK.
Leading LHC scientists were in London today for a discussion meeting about their progress.
Last year was spent “rediscovering” particles and forces that had already been uncovered over the past 50 years, both to verify their existence and to calibrate the LHC’s sensitive instruments.
Rolf-Dieter Heuer, professor and director general of Cern, the European Organisation for Nuclear Research, which coordinates the LHC project, said he had now “officially” told the team to “go into discovery mode”.
Speaking at a news conference at the Royal Society, he added: “I’m pretty confident that towards the end of 2012 we will have an answer to the Shakespearean question for the Higgs boson: to be or not to be.”
Guido Tonelli, an LHC researcher and professor from the University of Pisa in Italy, said the scientists had arrived at a “magic moment”.
“We are at the edge of the complete exploration of new territory,” he said.
Senior Cern scientist and professor Fabiola Gianotti, official from the Atlas experiment, said: “In the next two years we expect to settle the question of the Standard Model Higgs boson and to discover something new. Perhaps nature has prepared a surprise. The important thing is we have to remain humble, because as Newton said, what we know is a drop and what we don’t know is an ocean.”
Last month, leaked information from the Atlas detector led to rumours that the “God particle” had been found.
But Prof. Gianotti said careful analysis of the data had shown “no evidence” of the Higgs boson.
Prof. Heuer said: “Anything in blogs or leaks, don’t trust it at first sight.
“Of course we are very keen to share results with the public, so it’s not a question of hiding results. It’s that we don’t want to produce wrong results.”
The elusive Higgs boson is the last Standard Model particle still being hunted by scientists.
It belongs to a family of “gauge bosons” that mediate the forces of nature. Others include the photon, the W and Z bosons, and the gluon.
Theories have been suggested as alternatives to the Standard Model that do not require a Higgs boson. One of the leading ideas is string theory, which proposes that elementary particles are not “points” but “strings” with curled up higher dimensions.