Accelerated particles: Housed in a 27-kilometre-circumference tunnel under the French-Swiss border, the LHC is expected to be up and running by July or August.

Credit: CERN

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GENEVA: The world's biggest atom-smasher, now close to completion at the CERN (European Organisation for Nuclear Research) laboratory near Geneva, is a study in big numbers:

• The Large Hadron Collider (LHC) will whiz protons to 99.9999 per cent of the speed of light in two parallel beams in a ring-shaped tunnel, 27 kilometres (16.9 miles) long and up to 175 metres (568 feet) below the ground. The tunnel straddles the French-Swiss border.
• In top gear, the LHC will generate nearly a billion collisions per second. Above ground, a farm of 3,000 computers, will rapidly crunch this number down to about 100 collisions that are of the most interest. The data will then be sent out to a grid of institutions and universities around the world for analysis – a sort of mini-World Wide Web of its own.
• The tunnel is the world's largest fridge, with parts reaching a temperature as low as -271ºC, which is colder than deep space.
• The detectors are Herculean in scale. The biggest, called ATLAS, is 46 metres long and 25 metres high, or about half the size of the Notre Dame Cathedral in Paris. At 7,000 tonnes, ATLAS weighs almost as much as the Eiffel Tower, and has 3,000 km of cabling. Nearly 300,000 tonnes of rock were dug to house ATLAS and 50,000 tonnes of concrete were poured. In one year, ATLAS will generate 3,200 terabytes of raw data, equivalent to 160 times the three billion books in the U.S. Library of Congress.
• In the course of a 10-hour experiment, a beam might travel more than 10 billion kilometres, enough to get to Neptune and back. At full intensity, each beam will have the equivalent energy of a car travelling at 1,600 km/h. The LHC will use up 120 megawatts of power, equal to all the households in the Geneva area.
• LHC collisions will generate 14 teraelectronvolts (TeV), amounting to a high concentration of energy but only at an extraordinarily tiny scale. One TeV is the equivalent energy of motion of a flying mosquito.
• Some physicists have wondered whether the LHC will produce minute black holes and nasty (but so far entirely theoretical) phenomena called strangelets that would reduce Earth to a lump of hot, strange matter. CERN says any black holes would be so weak that they could not exert sufficient gravitational force to pull in surrounding matter. As for strangelets, CERN points out that Earth is battered by cosmic rays of much higher energy intensities, but the planet is still here.
• The price tag for building the LHC is put at 6.03 billion Swiss francs (A$6.5 billion), two-thirds of which went into materials and a third into paying for an army of thousands of physicists, engineers and technicians to design and install it.