The world's largest atom smasher has recorded its first high-energy collisions of protons, a spokeswoman said Wednesday. Physicists hope those collisions will help them understand suspected phenomena such as dark matter, antimatter and ultimately the creation of the universe billions of years ago, which many theorize occurred as a massive explosion known as the Big Bang. The collisions occurred Tuesday evening as the Large Hadron Collider underwent test runs in preparation for operations next year, said Christine Sutton of the European Organization for Nuclear Research, or CERN. Two beams of circulating particles traveling in opposite directions at 1.18 trillion electron volts produced the collisions, she said. The Atlas “experiment,” one of four major detectors in cathedral-sized rooms in the collider's underground tunnel at Geneva, had part of its equipment turned on and could register collisions. The operators plan many more collisions at lower energies so the experiments can calibrate their equipment.