antiparticle

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antiparticle

 [an″tĭ-pahr´tĭ-k'l]
either of a pair of elementary particles that have electric charges and magnetic moments of opposite sign and are the same in all other properties, such as mass, lifetime, and spin, e.g., the electron and positron. Every particle has an antiparticle. When antiparticles collide, they are annihilated, and their mass is converted to energy in the form of gamma rays.
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Antimatter was beaten 23 lengths over 2m1/2f at Galway last time but he ran better than the bare form suggests behind the well-handicapped
When matter and antimatter particles come into contact, they annihilate each other in a burst of energy -- similar to what happened in the Big Bang, some 14 billion years ago.
"What we're looking for is (to see) if hydrogen in matter and antihydrogen in antimatter behave in the same way," Jeffrey Hangst of the ALPHA experiment at the European Organization for Nuclear Research (CERN), said in a statement.
In classical cosmology a severe problem remains, due to the absence of observation of primordial antimatter. In 1967, Sakharov suggested that the Universe comprises two domains: the actual Universe and its twin Universe, each connected through a singularity [8-10].
For most processes, the laws of physics would be the same if matter were swapped with antimatter. But when this principle, known as charge parity, or CP, symmetry, is violated, matter and antimatter act differently.
Scientists believe that almost equal amounts of matter and antimatter were created in the Big Bang, but it remains an unsolved problem why the visible universe today is composed mostly of ordinary matter.
Measuring the electric charge of antihydrogen atoms is a way to study any subtle differences between matter and antimatter which could account for the lack of antimatter in the universe.
Alpha was the first experiment to trap atoms of antihydrogen - neutral antimatter atoms held in place with a strong magnetic field for up to 1,000 seconds.
Current theories predict that the properties of antimatter should be the same as those for matter, so the ALPHA team hit the antihydrogen with microwave signals at frequencies that would cause a spin flip in a normal hydrogen atom.
Scientists at The European Organisation for Nuclear Research are celebrating successfully capturing antimatter, which could help provide an insight into how the universe was created.
Antimatter particles match familiar particles such as protons and electrons but have the opposite electric charge.
They have capped five years of work by containing, for the first time, a few atoms of antimatter.