SCIENTISTS are trying to stop the most powerful experiment ever saying the black holes it will create could destroy the world.
Dubbed by some the Doomsday test, it will be carried out next week in the Large Hadron Collider (LHC), located 300ft underground near the French-Swiss border.
The machine is 17 miles long and cost £4.4billion to create.
When its switch is pulled on September 10, this atom-smasher will become a virtual time machine, revealing what happened when the universe came into existence 14 billion years ago.
New particles of matter are expected to be discovered, new dimensions found beyond the four known, as scientists re-create conditions in the first BILLIONTHS of a second after the Big Bang.
Experts even predict that millions of tiny black holes will be produced baby brothers of the monsters gobbling up dust and stars at the heart of the galaxies.
That is why boffins are now trying to stop the project with a last-ditch challenge in the courts.
They fear the LHC experimenters are tinkering with the unknown and putting mankind and our whole planet at risk.
The group responsible for the experiment, the European Nuclear Research Centre (CERN), says that these mini black holes will vanish as quickly as they are created.
But the anti-CERN brigade accuse the scientists of playing God, warning that no one can guarantee that the black holes will not survive, rapidly growing in size to suck the Earth out of existence in an instant.
But CERN, which includes several UK scientists, say their work is vital to unlock the secrets of matter that forms everything known in the universe.
In the experiment, atomic particles will be fired in opposite directions along the 17-mile long underground ring the length of the Circle Line on the London Underground.
They will travel so fast that they make 11,245 trips around the tunnel every SECOND.
From the collisions, boffins expect to discover a fundamental bit of the atom, called the Higgs boson, that is expected to exist but which has never been seen.
Professor Otto Rossler, from the Eberhard Karls University of Tubingen in Germany, is one of the scientists mounting the legal challenge at the European Court of Human Rights against 20 countries which are funding the project.
He said: It is quite plausible that these little black holes will survive and will grow and eat the planet from the inside out.
A CERN spokesman said: It will not be producing anything that does not already happen routinely in nature.