A theoretical constructivisation of mathematical economics
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
This thesis deals with some problems in mathematical economics, looked at constructively; that is, with intuitionistic logic. In particular, we look at the connection between approximate Pareto optima and approximate equilibria. We then examine the classically vacuous, but constructively nontrivial, problem of locating the exact point where a line segment crosses the boundary of a convex subset of RN. We also prove the pointwise continuity of an associated boundary crossing mapping. Turning to a rather different aspect of the theory, we discuss Ekeland's Theorem giving approximate minima of certain functions, as well as some fundamental notions in related areas of optimisation. The thesis ends with a discussion of some problems associated with the possible constructivisation of McKenzie's proof of the existence of competitive equilibria.