News : Mysteries of universe at focus of giant project

By Robert Evans

GENEVA (Reuters) - Scientists at a vast underground Swiss laboratory will launch an experiment on Wednesday to re-enact the "Big Bang" on a small scale to explain the origins of the universe and how it came to harbor life.

The Large Hadron Collider, or LHC, will use giant magnets housed in cathedral-size caverns to fire beams of energy particles around a 27-km (17-mile) tunnel where they will smash together near the speed of light. Computers will analyze particles given off for clues to what happened at the Big Bang.

Scientists at the CERN laboratory, near the foothills of the Jura mountains, will pursue long elusive concepts such as "dark matter," "dark energy", extra dimensions and, most of all, the "Higgs Boson" believed to have made it all possible.

"The LHC was conceived to radically change our vision of the universe," said CERN's French Director-General Robert Aymar. "Whatever discoveries it brings, mankind's understanding of our world's origins will be greatly enriched."

CERN scientists have been at pains to deny suggestions by some critics that the experiment could create tiny black holes of intense gravity that could suck in the whole planet.

The experiment is projected to restage trillions of times the moment some 15 billion years ago when, as cosmologists believe, an unimaginably dense and hot object the size of a small coin exploded, expanding rapidly to create stars, planets and eventually life on Earth.

The 10 billion Swiss franc ($9 billion) effort at CERN, the 20-nation European Organization for Nuclear Research on the edge of Geneva, begins with a relatively simple procedure: pumping a particle beam around the underground tunnel.

Technicians will first attempt to push the beam in one direction round the tightly-sealed collider, some 100 meters (yards) underground.

NO GUARANTEE

Once they have done that -- and CERN officials say there is no guarantee that success will come immediately or even in the first days -- they will project a beam, also at just under the speed of light, in the other direction.

And then, perhaps in the coming weeks, they will pump beams in both directions and smash the particles together -- but initially at low intensity.

Later, probably near the end of the year, they will move on to produce tiny collisions that will recreate the heat and energy of the Big Bang, a concept of the origin of the universe accepted by scientists.

What happens after these events -- which at their height could occur 600 million times a second -- will be tracked by ultra-sophisticated detectors wrapped around the LHC at the four collision points.

The detectors will monitor the billions of particles that will emerge from the fireballs, capturing on computer the way they come together, fly apart or just simply dissolve -- and passing the information on for detailed analysis.

It is in these conditions that scientists hope to find fairly quickly the Higgs Boson, named after Scottish scientist Peter Higgs who first proposed it in 1964 as the answer to the mystery of how matter gains mass.

Without mass, the stars and planets in the universe could never have taken shape in the eons after the Big Bang, and life could never have begun -- on Earth or, if it exists as many cosmologists believe, on other worlds either.

The experiment is not without its detractors.

Websites on the Internet, itself created at CERN in the early 1990s as a means of passing particle research results to scientists around the globe, have been inundated with claims that the LHC will create black holes sucking in the planet.

"Nonsense," say the most trenchant of CERN scientists, who, with colleagues in the United States and Russia issued a detailed report last weekend arguing that such a disaster was out of the question.

"The LHC is safe, and any suggestion that it might present a risk is pure fiction," said Aymar in a comment on the report. British physicist Brian Cox said the "end of the world" ideas were "nonsense.... spread by conspiracy theorists."