This award supports a visit by Professors Michael Stob of Calvin College, Steffen Lempp of the University of Wisconsin, and Richard Shore of Cornell University, to Victoria University, New Zealand, to work with Professor Rodney Downey. All have collaborated successfully in the past and have several on-going projects in recursion theory, a branch of mathematical logic. All concern the study of certain algebraic structures which arise naturally from the study of effective computability. The primary structures they will study are the lattice of recursively enumerable sets and the uppersemilattices of the Turing degrees and the recursively enumerable Turing degrees. The principal method they will employ is the priority method.
