Locus theorems in ancient Greek geometry.

Abstract:During the third century B.C. Greek mathematicians (including Euclid and Apollonius) took a particular interest in locus theorems and their applications in problem solving. A Greek locus theorem demonstrated that a geometrical object (typically a point) having a defined relation to given objects lies on a geometrical object (typically a line or surface) that can be constructed from the givens. A classification was devised of locus theorems, and construction problems in general, according to whether they could be solved using only the postulates in Euclid's Elements, i.e. straight lines and circles, or required conic sections or special curves. An interesting question is whether anyone in antiquity broke from this rigid conception of loci by defining a curve or surface as a locus.