Antimatter is the enigmatic twin of ordinary matter, possessing the same mass but with an opposite electrical charge. Under current theory, the Big Bang explosion that initiated the universe should have produced equal amounts of matter and antimatter. However, antimatter can be synthesized under controlled conditions, as in the ALPHA experiment, which used antihydrogen created at CERN. "The nearly complete absence of naturally occurring antimatter is one of the great questions facing physics," Wurtele said. "No matter how pretty the theory, physics is an experimental science," Fajans said.

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Persons: Jonathan Wurtele, Joel Fajans, Wurtele, Einstein, William Bertsche, Bertsche, Fajans, Will Dunham, Rosalba O'Brien Organizations: European Center for Nuclear Research, CERN, Enterprise, University of California, ALPHA, UC Berkeley, University of Manchester, Thomson Locations: Geneva, Switzerland, Berkeley, England, Washington