The world’s most powerful particle accelerator, the Large Hadron Collider, suffered its second embarrassing setback recently. Not long after a leak of coolant destroyed some of the magnets that guide the energy beam (forcing officials to postpone the restart of the new machine), the whole operation has had to be shut down after a bird dropped a piece of bread onto a section of the accelerator. “This incident won't delay the reactivation of the facility later this month, but exposes yet another vulnerability of the what might be the most complex machine ever built,” writes Popular Science. “With freak accident after freak accident piling up over at CERN, the idea of time traveling particles returning from the future to prevent their own discovery is beginning to seem less and less far fetched.”