In various countries, plaintiffs have sought court orders to halt the operation of the Large Hadron Collider at CERN near Geneva, Switzerland, with the most extraordinary of allegations: that the experiment may create a black hole that will devour the Earth.

Up until now, the various lawsuits filed against the LHC have faltered. But if the right kind of claim is filed in the proper court, a judge may soon have to face the question of whether an injunction might be needed to save the world.

Injunctions are court orders that command persons to do or refrain from doing something. They are relatively routine, for example when a building of historic significance is threatened with demolition. But wading into the world of particle physics to shut down the LHC would be a forbidding proposition for anyone in judges’ robes.

In deciding whether or not to issue an injunction, courts engage in what lawyers refer to as a “balancing test”. The idea is that the court weighs the hardships that would be endured by both parties if the injunction were or were not issued, taking into account the likelihood and severity of the alleged consequences. The test closely resembles what is portrayed by courthouse statues around the world – Lady Justice holding up scales to measure the relative weight of the plaintiff’s and defendant’s cases.

So let’s do the balancing test for the LHC case. The hardship CERN would suffer from an injunction is enormous – idling thousands of workers and equipment worth billions of euros, and upending a great scientific adventure. That weighs on the scales heavily. But on the other side is an Earth-mass black hole. That not only tips the scales, it eats them up.

The remaining task is to determine whether the questions raised are sufficiently serious. For that, a court must take a careful look at the scientific controversy. Yet the physics involved is difficult terrain even for physicists. A judge with maybe just a few days to ponder has scant chance of learning the science well enough to confidently decide who is right and who is wrong.

Story continues: http://www.newscientist.com/article/mg20527485.700-cern-on-trial-could-a-lawsuit-shut-the-lhc-down.html

Professor Brian Cox, who works on the ATLAS experiment at the Large Hadron Collider, will be giving this year’s Voltaire Lecture for the BHA on 6th April.