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A whole new world!

A whole new world! PHYSICISTS have created the first atoms of antimatter, giving scientists a glimpse of what they say could be a "completely new anti-world". This historical achievement was announced on January 4, after months of careful checking of data. According to scientists, it is quite possible that the universe could contain stars and planets which are made entirely of objects constituted of antimatter that until now scientists could only imagine but never thought would emerge as reality. The antimatter atoms were produced near Geneva in Switzerland, last September, at the European Laboratory for Particle Physics (CERN) by physicist Walter Oelert and his team from ErlangenNuremberg University in Germany. Needless to say, the results of the tests were a triumph for CERN.

Scientists at five other research centres, which include Harvard and Chicago, were also working to produce antimatter atoms. They had already created anti-electrons, also called positrons, and anti-protons, but had really not succeeded in combining them into an atom.

Ordinary atoms consist of a nucleus made of protons and neutrons, surrounded by a variable number of particles which are called electrons. The number of protons in the nucleus of an atom determines what kind of an element it is. For instance, a hydrogen atom is constituted of one proton plus one electron.

Antimatter atoms have the same basic structure. But they are made up of anti-particles. Every sub-atomic particle, like a proton, neutron or electron, is known to have a corresponding anti-particle, which has the same mass and spin, but an opposite electric charge. A fascinating quality of antimatter is that when it meets matter - the substance that all things on Earth are made of - the two substances instantly annihilate each other while releasing a burst of energy.

In the laboratory experiments, the antimatter atoms existed for just 40 billionth of a second before annihilation. The next step for Oelert and his team was to trap and hold the atoms of antimatter long enough to compare them with ordinary atoms. According to current scientific theories, both the atoms should be exactly the same. If they are not, then the understanding of the scientists about our universe will be turned on its head.

"This discovery opens the door into a completely new anti-world," exclaimed Neil Calder, a spokesperson of CERN. "This may be a tiny Alice in Wonderland door ... through which we can get to a completely new understanding of the reality of the universe."

Scientists observing the event in other places also hailed the discovery, but said it was only the first step in a long process. Gerald Gabrielse, a professor of physics at Harvard, described the results as a "very interesting demonstration". But he said that further research was needed to observe the antimatter atoms at slower speed and compare them with ordinary atoms, "We will have to wait and see if we can compare the atoms with high accuracy to see if they are the same or not. That is where the real punchline is," Gabrielse said.

John Eades, the British coordinator of experiments at CERN said that the real challenge had been in producing enough of the right kind of collisions between ordinary particles to create a few anti-hydrogen atoms.

Understandably, anti-particles do not exist naturally on Earth, but were produced accidentally by scientists some 50 years ago, when normal particles collided at tremendous speeds. Now, despite having achieved the feat which could be repeated in the laboratory, Oelert was "extremely pessimistic" that his discovery would ever lead to a new type of energy. "Even if it were possible to produce a lot of antimatter, the technological problems of keeping it are enormous, " he said.

Some scientists are already dreaming that antimatter might one day be developed as a very high potency fuel to be used for inerstellar rockets or super-bombs for, as antimatter gets annihilated when combined with ordinary matter, it converts mass to energy far more efficiently than does a nuclear bomb. Not a very welcome idea to the anti-nuke lobby.

"We are especially interested in hydrogen and anti -hydrogen," Fades said, "not only because of their structural simplicity, but because 90 per cent of the mass of the universe is hydrogen. Even slight differences in the properties of hydrogen and anti-hydrogen could help explain why the universe, as we know it, consists entirely of matter rather than antimatter."

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