Q&A: Large Hadron Collider

2008-09-11 21:23

Geneva - The Large Hadron Collider was built to help scientists learn more about the nature of the universe and the origins of all matter.

Following are questions and answers about what the Large Hadron Collider could - and won't - reveal.

Q: What is the Large Hadron Collider?

A: It is the world's most powerful particle accelerator. It is buried inside a 27km tunnel below the earth and surrounded by massive detectors.

Q: What does "hadron" refer to?

A: It is a particle - such as a proton or neutron - that is found in the nucleus of an atom.

Q: Who built the collider and how much did it cost?

A: The project was conceived in 1984 by scientists at the European Organisation for Nuclear Research, or CERN. The organisation's 20 member nations along with observer countries like the United States and Japan have contributed about $10bn toward the project.

Q: How does the collider work?

A: The collider fires protons around the tunnel at near light speed - almost 300 000km per second. Supercooled magnets guide the protons in opposite directions around a near-vacuum until they collide at four points inside the tunnel.

Q: What do the detectors do?

A: As protons collide, the detectors will search for evidence of extra dimensions to the three of space and one of time that we know of.

They will also look for the "dark matter" believed to make up most of the universe, antimatter that mirrors all known matter, and the elusive Higgs-boson particle, which could explain how all other particles get their mass. All of these have previously only been theorised, but not confirmed.

Q: What about the "Big Bang" part of the experiment?

A: One of the detectors will smash together lead ions to simulate conditions shortly after the Big Bang, which is believed to have started the universe 13.7 billion years ago. Scientists hope to learn from this how matter was formed.

Q: What else do scientists hope to learn?

A: If the collider proves the existence of new particles, it could test the dominant physics hypotheses of "string theory," which seeks to reconcile quantum mechanics and gravity in an all-encompassing formula.

Q: Is the experiment safe?

A: Some people have objected to the collider because they fear it could create black holes or release massive amounts of energy that would destroy the planet. CERN and leading particle physicists insist there is no danger. Other scientists have calculated the odds of this happening as too minute to worry about. This hasn't stopped bookmakers from taking bets on whether the end of the world is near.

Q: Will the collider prove the existence of God?

A: No. The experiment will examine what happened shortly after the universe was created. It does not seek to confirm or deny the existence of any supernatural being.