A US District Court in Hawaii has been petitioned to stop the operation of the Cern Large Hadron Collider (LHC) over fears that it might cause the end of the world.
Walter Wagner, a former nuclear safety officer, has filed the suit as he fears that the LHC could create a mini black hole that could swallow the planet.
He also expressed concerns that transmuting matter into so-called strangelets could change all other matter into a similar form.
The claims have been dismissed by physicists at Cern. "Some physicists suggest that microscopic black holes could be produced in the collisions at the LHC," said the organisation in a statement.
"However, these would only be created with the energies of the colliding particles, which is equivalent to the energies of mosquitoes."
Cern insisted that no microscopic black holes produced inside the LHC could generate a strong enough gravitational force to pull in surrounding matter.
"If the LHC can produce microscopic black holes, cosmic rays of much higher energies would already have produced many more," the statement added.
"Since the Earth is still here, there is no reason to believe that collisions inside the LHC are harmful."
This is not the first time that the safety of the LHC has been called into question. Russian scientists suggested last month that time travel may occur when the LHC fires up later this year.
It is unclear why Wagner's lawsuit has been filed in Hawaii, since the LHC is located under the Swiss/French border and has no links with the US.
The LHC forms a 27km circle and is the world's largest piece of laboratory equipment.
Once active it will fire a stream of protons into each other at near light speed. The resulting collisions will generate examples of material found in the first seconds of the universe.
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