The positronium is a particle created when you bind together an electron and its antimatter opposite, the positron. It’s shortlived and unstable particle, existing for only about 142 nanoseconds before decaying into two gamma ray particles–however, this strangle particle ma help us solve some of the biggest mysteries in the universe. How? It can be used to create a Bose-Einstein condensate, a special, ultra-cold form of matter in which particles move so slowly that it’s possible to observe their quantum effects. This week’s Dreamland tells you what kind of extraordinary information we may discover this way.Meanwhile, at CERN, billions of particles continue to collide with each other at h igh speed (close to the speed of light). Scientists there may eventually discover parallel universes, unknown forms of matter and extra dimensions. It turns out that only 4% of the particles in the universe have been identified, because the rest is made up of what is called dark matter.