The ALPHA collaboration has achieved one of the long-stated goals of the physics programme at CERN’s Antiproton Decelerator: magnetic trapping of antihydrogen atoms.

Antimatter is difficult to make, let alone store. Jeffrey Hangst describes how ALPHA, an experiment attempting to trap antihydrogen at CERN, overcomes some of the difficulties and he questions the reality of ever making more than the tiniest amounts of antimatter.

I efteråret 2002 lykkedes det for første gang forskere at fremstille koldt antistof i form af antibrint-atomer. Nu vil forskerne så forsøge at fange disse antiatomer. Men hvordan fanger man noget, der tilintetgøres så snart det kommer i kontakt med almindeligt stof?

Half a century since the discovery of the antiproton, and more than 70 years since that of the positron, researchers at CERN can routinely produce millions of antihydrogen atoms. Mike Charlton and Jeffrey Hangst explain how these remarkable anti-atoms could be our best bet for understanding one of the most fundamental symmetries of nature.