A Topological Study of the Closed Fragment of GLP

摘要

In this article, we study the canonical model for the closed fragment of GLP and establish its precise relationship with a universal model constructed by Ignatiev. In particular, we effectively characterize the canonical model in terms of a coordinate system based on sequences of ordinals up to _0. We then define a simple topological model of this logic by defining a natural polytopology on the ordinal _0 itself.