Antimatter held for questioning

摘要

For physicists, a bit of antimatter is a precious gift indeed. By comparing matter to its counterpart, they can test fundamental symmetries that lie at the heart of the standard model of particle physics, and look for hints of new physics beyond. Yet few gifts are as tricky to wrap. Bring a particle of antimatter into contact with its matter counterpart and the two annihilate in a flash of energy.