PEOPLE who fear a powerful atom-smashing machine, due to start operations next week, will cause Earth to be gobbled up or reduced to grey goo can rest assured, according to a new study.
The Large Hadron Collider (LHC) has been shadowed by internet-fuelled concerns that it will release energies so powerful that it will create a rogue black hole that will engulf the planet, or a "strangelet" particle that would transform Earth into a lump of strange matter.
But the new report, written by the machine's maker, claims these fears are unfounded.
It said the LHC will replicate collisions that already occur naturally when Earth runs into the path of high-energy cosmic rays.
"Nature has already conducted the equivalent of about a hundred thousand LHC experimental programmes on Earth — and the planet still exists," it said.
The assessment was written by five physicists at LHC's operator, the European Organisation for Nuclear Research (CERN) in Geneva.
CERN has asked them to take a fresh look at a safety assessment written by its scientists in 2003 which first gave the project the green light.
The LHC, installed in a circular 27km tunnel on the French-Swiss border, is to start unleashing a beam of protons early next Thursday in the first stage of its commissioning process.
Two parallel beams of particles, one going clockwise and the other anti-clockwise, will blast around the underground ring.
At four locations on the ring, superconducting magnets will bend the beams so that groups of protons smash into each other in a giant chamber which is swathed with detectors to record the resulting sub-atomic debris.
This invisible rubble could help resolve some of the biggest questions in physics, such as the nature of mass, the weakness of gravity and whether, as some theoreticians suggest, there exist dimensions beyond our own.
The new Safety Assessment Report said any black holes produced by the collider would be "microscopic" and decay almost immediately, as they would lack the energy to grow or even be sustained.
"Each collision of a pair of protons in the LHC will release an amount of energy comparable to that of two colliding mosquitoes, so any black hole produced would be much smaller than those known to astrophysicists," the report said.
As for the hypothesised "strangelets," the report referred to data from the Relativistic Heavy-Ion Collider at the Brookhaven National Laboratory in New York to say that these would not be produced during collisions in the LHC.
The review is published in a journal of the Institute of Physics, London.
France has also asked a French watchdog agency, the Nuclear Safety Authority (ASN), to carry out a safety appraisal of the LHC.
On August 29, the European Court of Human Rights, based in Strasbourg, France, tossed out a last-ditch legal bid to stop the LHC's switch-on.
The suit had been filed by a group of European citizens, led by a German biochemist, Otto Roessler, of the University of Tuebingen.
The LHC will begin operation on September 10th.
LHC on Wikipedia - http://en.wikipedia.org/wiki/Large_Hadron_Collider
How it works (rap video) - http://www.youtube.com/watch?v=j50ZssEojtM