THE BIG BANG (WE HAVE SURVIVED)

Scientists at the European Organisation for Nuclear Research (CERN) started up a huge particle-smashing machine on Wednesday, aiming to re-enact the conditions of the "Big Bang" that created the universe.

The Large Hadron Collider (LHC) is the largest and most complex machine ever made and the platform for what experts say is the largest scientific experiment in human history.

Tests conducted inside the tightly-sealed chamber, buried under the Swiss-French border, could unlock the remaining secrets of modern physics and answer questions about the universe and its origins.

The 10 billion Swiss franc (5 billion pound) machine's debut came as a blip on a screen in CERN's control room, with a particle beam the size of a human hair appearing in the tightly-sealed 27-km (17-mile) circular tunnel.

"We've got a beam on the LHC," project leader Lyn Evans told his colleagues, who burst into applause at the news.

The several hundred physicists and technicians huddled in the control room later celebrated loudly again when a particle beam completed a trajectory of the accelerator in one direction, a key step a CERN spokeswoman described as "fantastic."

Scientists will next send a beam around the LHC in the other direction to test that the path is clear.

Once that is established, it will be possible to send beams in both directions simultaneously to create high-energy collisions at close to the speed of light.

Scientists around the world are eagerly anticipating data on those minuscule crashes. One possibility is that they will cause the creation of matter -- proving correct the theory that there exists a "Higgs Boson" that gives matter its mass.

The elusive Higgs Boson is a theoretical particle, also known as a "God particle", and is named after Scottish physicist Peter Higgs, who first postulated in 1964 that it must exist.

Doomsday writers have also fanned fears that the experiment could create anti-matter, or black holes, spurring unprecedented public interest in particle physics ahead of the machine's start-up. CERN has insisted that such concerns are unfounded.