Chike Obi solves 361-year-old maths puzzle

By Akin Jimoh

BY plain brainwork and without the use of modern technological aid such as
computers, world acclaimed Nigerian mathematician, Prof. Chike Obi, has
given scientific
proof to a 361-year old mathematical puzzle known as Fermat's Last Theorem.

The theorem, well known among mathematicians and other allied professions,
was enunciated by one of the two leading mathematicians of the first half of
the 17th Century, Pierre de Fermat, a French. By far, the best known of
Fermat's many theorems, it states that the equation xn+yn=zn; where x,y,z,
and n are positive integers, has no solution if n is greater than two.

Fermat had, on this particular theorem, which appeared in the margin of
Diophantus
Arithmetic, stated: "I have discovered a truly wonderful proof of this
proposition, but the margin is too small to contain it."

Two Western researchers had in 1994 solved the problem using modern
technological aid. But Nigeria's Obi, in a summary of his seminal paper,
used a method which "looks
very much like the way Fermat must have proved his theorem in the 17th
Century." Obi's
research, conducted at his Nanna Institute for Scientific Studies based in
Onitsha, Anambra State, has just been published in the international journal
{Algebras Groups and Geometries}Volume 15, Pages 289 to 299 (1998). In this
work, Obi presented an elementary proof of the theorem. The science
community, especially in Nigeria and other developing countries, is agog
with celebration that such scholarship is coming from Africa. Nigerian
Academy of Science (NAS) President, Professor Anya O. Anya described
{Fermat's Last Theorem} as one of the most famous problems in Numbers
Theory. Indeed, the academy is planning to celebrate Obi's feat and many
others of its fellows, NAS Secretary, Prof. Sulaiman Adekola said.
Besides, measures will shortly be put in place by the academy to popularise
Obi's works and other breakthroughs in science in Nigeria.

Another professor of mathematics, Jerome Ajayi Adepoju who described Obi as
"my senior colleague for many years," said the simplicity of the method
employed by the
University of Lagos emeritus professor stands it out from what other
mathematicians have done. This, according to him, proved that Fermat, in his
simplistic way and using the technology of the 17th Century, was indeed
right.

The theorem has been described as a general diophantine equation which, in
Adepoju's words,is "a special case." It was indeed not until November 1994
that two
mathematicians, Andrew Wiles and Richard Taylor, gave a complete and
acceptable proof.

Adepoju said: "Wiles and Taylor in their proof made use of the work of
Taniyama - Shimura - Weil conjecture for semi-stable elliptic curves, as
well as the results of Frey, Serve and Ribbat. In view of the complexity and
the amount of mathematics involved in the proof, some of which were not
known or developed at the time of Fermat, one wonders if indeed Fermat
actually had a valid proof or what his proof looked like.

"If indeed he had a proof, it is unlikely to be along the same lines of
argument as Wiles' and Taylor's proof."

According to the scholar, that Obi's method used the principle adopted by
Fermat in the 17th Century makes it more acceptable and a true reflection of
Fermat's thinking
at that time.

Obi, 78, is an emeritus professor of mathematics at the University of Lagos
since 1985. Born on April 7, 1921 and married with four children, he retired
from academia to
found the Nanna Institute for Scientific Studies, Onitsha.

A Fellow of the Nigerian Academy of Science, the world renowned mathematics
scholar won the Ecklund Prize from the International Centre for Theoretical
Physics for original work in Differential Equations, and pioneering works in
mathematics in Africa. He
had earned his doctoral degree in 1950, specialising in Non-linear
Differential Equations at the Pembrooke College, University of Cambridge,
England.

Besides his scholarly enterprise, Obi used to be a political activist - with
many publications on mathematics and the Nigerian political system.

Praising the eminent scholar, Adepoju said at the weekend that the proof by
other mathematicians, used a high measure of sophistication which "was not
known during Fermat's time." He added: "What we have in this (Obi's) paper
is what Fermat's proof looked like."

According to him, humanity has much to gain from mathematics. "It has a lot
of relevance.  Everything you do is mathematics, it depends on the area.
People have gone to space using principles and theories of mathematics.
Finance - calculation of simple or compound interest, buying and selling and
other day to day activities like walking
the road even employ mathematics."