Diophantus of Alexandria (dates unknown, lived and died between 200AD and 300AD) was an Alexandrian
mathematician.
He wrote a
series of books (many now lost) called
Arithmetica that deal with solving
algebraic equations.
Pierre de Fermat studied
Arithmetica and it was in the margin in his copy that he made the fateful
note in 1637 that a certain
equation similar to the Pythagorean
equation considered by Diophantus has no solutions,
and he found "a truly marvelous
proof of this proposition", the celebrated
Fermat's Last Theorem. This led to
tremendous advances in
number theory, and the study of
diophantine equations ("diophantine
geometry") and of
diophantine approximations remain important areas of mathematical research. Diophantus was the first Greek
mathematician
who recognized fractions as
numbers; thus he allowed positive
rational numbers for the coefficients and solutions.
In modern use, diophantine equations are usually algebraic equations with integer coefficients, for which integer
solutions are sought.
One of the
Famous People on this site.