KentuckyFC writes "Just when you thought it was safe to switch on the LHC (though it won't be for a while yet), another nightmare scenario has emerged that some critics worry could cause the particle accelerator to explode. The culprit this time is not an Earth-swallowing black hole but a 'Bose supernova' in the accelerator's superfluid helium bath. Physicists have been playing with Bose Einstein Condensate (BECs) for over 10 years now. But in 2001, one group discovered that placing them in a powerful magnetic field could cause the attractive forces between atoms to become repulsive. That caused their BEC to explode in a Bose supernova — which they called a 'Bosenova,' a name that fortunately did not catch on. This was little more than a curiosity when only a microscopic blob of cold matter was involved. But superfluid liquid helium is also BEC. And physicists have suddenly remembered that the LHC is swimming in 700,000 liters of the stuff while being zapped by some of the most powerful magnetic fields on the planet. So is the LHC a Bose supernova waiting to go off? Not according to the CERN theory division, which has published its calculations that show the LHC is safe (abstract). They also point out that no other superfluid helium handling facility has mysteriously blown itself to pieces."