The Mysterious Case of the Excess Positrons

In 2008, the European satellite PAMELA detected a surprisingly large concentration of high energy positrons above our atmosphere. The presence of so many positions, the anti-matter counterpart of electrons, goes against theoretical predictions but has been verified by other detectors. In new research published earlier this month by the AAAS journal Science, a team of researchers from Germany, Mexico, Poland, and the United States now cast doubt on one of the leading explanations for the mysterio...