In practice, though, we do not see them.Īt the start of the universe, cosmologists think, there was probably an infinitesimally small excess of matter particles over antimatter particles. For every particle of matter in the universe, there should be a particle of antimatter. The laws of physics do not differentiate between matter and antimatter so, at the creation of the universe during the big bang, equal amounts of both should have been made.

The question scientists want to answer is why antimatter seems to be missing from the universe. You hold them for a thousand seconds, you can be quite sure they're in the state you want to study.' It takes some fraction of a second for these atoms to get to the ground state. That's not the state we want to study – we want to study the ground state. 'We make our antihydrogen in excited states, the positron is at a larger distance and has more energy. 'If you think of an atom as a little planetary system with an electron orbiting the nucleus (or, in our case, the positron orbiting the antiproton), the ground state is the one where the electron or positron is closest to the nucleus,' said Hangst. For Hangst and his team, keeping the antihydrogen in place for more than a just few seconds will allow them to study the antimatter in its most natural state. If 1kg of antimatter came into contact with 1kg of matter, the resulting explosion would be the equivalent of 43 megatons of TNT – about 3,000 times more powerful than the bomb that exploded over Hiroshima.Ĭreating big explosions is not on the agenda for Hangst, however. When a particle meets its antiparticle pair, the resulting annihilation turns their masses into pure energy, as determined by Albert Einstein's equation, E=mc 2.

Similarly, a proton and an antiproton are the same size and have the same mass, but have positive and negative charges respectively.

An electron has a negative charge, whereas its antiparticle, the positron, has a positive charge, and both have an identical mass. Particles of matter and antimatter are identical, except for an opposite electrical charge.

We're getting information about how they're behaving in the trap.'Īntimatter was first postulated by the British physicist Paul Dirac in 1930 while working on a way to reconcile the ideas of quantum mechanics with Albert Einstein's theory of relativity. With 38, that was difficult, but with 300 it starts to look like something you can make averages out of. 'We've studied what's going on with these atoms while they're in the trap, how they're moving, what energy or velocity they have. Jeffrey Hangst of the University of Aarhus in Denmark, who led the experiments, said that the purpose of the study was to compare antimatter with atoms of normal matter. In their latest work, published in this month's edition of Nature Physics, they trapped 309 antihydrogen atoms for varying amounts of time up to 1,000 seconds (just over 16 minutes). The same scientists, based at the Alpha collaboration in Cern, were the first to trap antihydrogen last year when they created and held on to 38 atoms of the stuff for 172 milliseconds in a strong magnetic field.

Real life antimatter