Antimatter is old hat to physicists. After all, it was way back in 1933 when they discovered the first antiparticles--exact duplicates of ordinary particles except that they have an opposite electric charge. Since it usually takes only a few millionths of a second for antimatter particles to come into contact with their matter counterparts, thus annihilating themselves in tiny bursts of energy, physicists have concentrated on finding ways to make them sit still long enough to do something interesting with them. In particular, they have been trying for 15 years to combine an antiproton with an antielectron to form an antihydrogen atom.
Last January a team led by Walter Oelert of the Institute for Nuclear Physics in Jülich, Germany, announced that it had made nine atoms of antihydrogen--without first having to slow down the particles. The researchers used a particle accelerator at cern, the European Laboratory for Particle Physics in ...
