Ordinary matter has negatively charged electrons circling a positively charged nuclei. Anti-matter has positively charged electrons - positrons - orbiting a nuclei with a negative charge - anti-protons. Only anti-protons and positrons are able to be produced at this time, but scientists in Switzerland have begun a series of experiments which they believe will lead to the creation of the first anti-matter element -- Anti-Hydrogen.
The Research
Early scientists often made two mistakes about anti-matter. Some thought it had a negative mass, and would thus feel gravity as a push rather than a pull. If this were so, the antiproton's negative mass/energy would cancel the proton's when they met and nothing would remain; in reality, two extremely high-energy gamma photons are produced. Today's theories of the universe say that there is no such thing as a negative mass.
The second and more subtle mistake is the idea that anti-water would only annihilate with ordinary water, and could safety be kept in (say) an iron container. This is not so: it is the subatomic particles that react so destructively, and their arrangement makes no difference.
Scientists at CERN in Geneva are working on a device called the LEAR (low energy anti-proton ring) in an attempt to slow the velocity of the anti-protons to a billionth of their normal speeds. The slowing of the anti-protons and positrons, which normally travel at a velocity of that near the speed of light, is neccesary so that they have a chance of meeting and combining into anti-hydrogen.
The problems with research in the field of anti-matter is that when the anti-matter elements touch matter elements they annihilate each other. The total combined mass of both elements are released in a spectacular blast of energy. Electrons and positrons come together and vanish into high-energy gamma rays (plus a certain number of harmless neutrinos, which pass through whole planets without effect). Hitting ordinary matter, 1 kg of anti-matter explodes with the force of up to 43 million tons of TNT - as though several thousand Hiroshima bombs were detonated at once.
So how can anti-matter be stored? Space seems the only place, both for storage and for large-scale production. On Earth, gravity will sooner or later pull any anti-matter into disastrous contact with matter. Anti-matter has the opposite effect of gravity on it, the anti-matter is 'pushed away' by the gravitational force due to its opposite nature to that of matter. A way around the gravity problem appears at CERN, where fast moving anti-protons can be held in a 'storage ring' around which they constantly move - and kept away from the walls of the vacuum chamber - by magnetic fields. However, this only works for charged particles, it does not work for anti-neutrons, for example.
The Unanswerable Question
Though anti-matter can be manufactured, slowly, natural anti-matter has never been found. In theory, we should expect equal amounts of matter and anti-matter to be formed at the beginning of the universe - perhaps some far off galaxies are the made of anti-matter that somehow became separated from matter long ago. A problem with the theory is that cosmic rays that reach Earth from far-off parts are often made up of protons or even nuclei, never of anti-protons or antinuclei. There may be no natural anti-matter anywhere.
In that case, what happened to it? The most obvious answer is that, as predicted by theory, all the matter and anti-matter underwent mutual annihilation in the first seconds of creation; but why there do we still have matter? It seems unlikely that more matter than anti-matter should be formed. In this scenario, the matter would have to exceed the anti-matter by one part in 1000 million.
An alternative theory is produced by the physicist M. Goldhaber in 1956, is that the universe divided into two parts after its formation - the universe that we live in, and an alternate universe of anti-matter that cannot be observed by us.
The Chemistry
Though they have no charge, anti-neutrons differ from neutrons in having opposite 'spin' and 'baryon number'. All heavy particles, like protons or neutrons, are called baryons. A firm rule is that the total baryon number cannot change, though this apparently fails inside black holes. A neutron (baryon number +1) can become a proton (baryon number +1) and an electron (baryon number 0 since an electron is not a baryon but a light particle). The total electric charge stays at zero and the total baryon number at +1. But a proton cannot simply be annihilated.
A proton and anti-proton (baryon number -1) can join together in an annihilation of both. The two heavy particles meet in a flare of energy and vanish, their mass converted to high-energy radiation wile their opposite charges and baryon numbers cancel out. We can make antiprotons in the laboratory by turning this process round, using a particle accelerator to smash protons together at such enormous energies that the energy of collision is more than twice the mass/energy of a proton. The resulting reaction is written:
p + p p + p + p + p
Two protons (p) become three protons plus an antiproton(p); the total baryon number before is:
1 + 1 = 2
And after the collision it is:
1 + 1 + 1 - 1 = 2
Still two.
Anti-matter elements have the same properties as matter properties. For example, two atoms of anti-hydrogen and one atom of anti-oxygen would become anti-water.
The Article
The article chosen reflects on recent advancements in anti-matter research. Scientists in Switzerland have begun experimenting with a LEAR device (low energy anti-proton ring) which would slow the particle velocity by a billionth of its original velocity. This is all done in an effort to slow the velocity to such a speed where it can combine chemically with positrons to form anti-hydrogen.
The author of the article, whose name was not included on the article, failed to investigate other anti-matter research laboratories and their advancements. The author focused on the CERN research laboratory in Geneva. 'The intriguing thing about our work is that it flies in the face of all other current developments in particle physics' .
The article also focused on the intrigue into the discovering the anti-matter secret, but did not mention much on the destruction and mayhem anti-matter would cause if not treated with the utmost care and safety. Discovering anti-matter could mean the end of the Earth as we know it, one mistake could mean the end of the world and a release of high-energy gamma rays that could wipe out the life on earth in mere minutes.
It was a quite interesting article, with a lot of information that could affect the entire world. The article, however, did not focus on the benefits or disadvantages of anti-matter nor did it mention the practical uses of anti-matter. They are too expensive to use for powering rocket ships, and are not safe for household or industrial use, so have no meaning to the general public. It is merely a race to see who can make the first anti-matter element.
Conclusion
As research continues into the field of anti-matter there might be some very interesting and practical uses of anti-matter in the society of the future. Until there is a practical use, this is merely an attempt to prove which research lab will be the first to manufacture the anti-matter elements.
