FREE ESSAY ON ANTI-MATTER

ANTI-MATTER

Anti-Matter
Introduction
Ordinary matter has negatively charged electrons circling a positively charged nuclei.
Anti-matter however 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.
(Encarta 99)
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. (Encarta
99)
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) they are attempting 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 near the speed of light, is necessary 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 (along with 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. (Encarta 99)
So how can anti-matter be stored? Outer 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 slowly manufactured, 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. (Encarta 99)
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.
(Galactic Positron Annihilation) The two heavy particles meet in a flare of energy and
vanish. Their mass is converted to high-energy radiation while 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. (Galactic
Positron Annihilation)
The Article
The article I read about on the Internet, reflects on recent advancements in anti-matter
research. Scientists in Switzerland have begun experimenting with a LEAR device 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. (Galactic Positron Annihilation)
The author of the article, whose name was not included on the article, failed to
investigate any other anti-matter research laboratories and their advancements. The
author focused on the CERN research laboratory in Geneva.(Encarta 99)
The article also focused on the conniving 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 release of high-energy gamma rays
that could wipe out the life on earth in mere minutes.(Encarta 99)
It was a quite interesting article, with a lot of information that could affect all of
humanity. The article, however, did not address on the advantages 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,
therefore having no meaning to the general public. It is simply a race to see who can
make the first anti-matter element. (Galactic Positron Annihilation)
Conclusion
As research continues into the field of anti-matter there might be some very interesting
and practical uses of anti-matter in the future of society. Until there is a practical
use, this is barely an attempt to prove which research lab will be the first to
manufacture the anti-matter elements. 
Works Cited Page
Encarta 1999, Articles on Matter and Anti-Matter
Galactic Positron Annihilation,
http://www.astro.nwu.edu/astro/purcell/511kev/mcgraw.html