Topological aspects of the classical logic

Khanaki, Karim

doi:10.30465/lsj.2019.4490

Topological aspects of the classical logic

Document Type : Research

Author

karim khanaki

https://doi.org/10.30465/lsj.2019.4490

Abstract

Classical first-order logic is the most common logic in mathematics applications as well as in the study of logical foundations. From a long time ago, the only link between logic and mathematical topology was limited to the concept of type spaces, and there were no other links between these two domains. Recently, the basic links between these two branches (i.e. logic and topology) have been created, which have led to many applications in both areas of logic as well as in topology. In this article, we will study some of the most important links between these two branches of mathematics as well as their applications. One of the key concepts in mathematical logic and model theory is the concept of stability, which has a completely combinational statement. In this paper, we show that this concept is equivalent to a topological concept for a certain set of functions, and using this we prove a fundamental theorem of Shelah stability theory. We also describe the relationship between the concept of dependence and a topological property of a set of functions, and provide topological proofs of some of the important achievements of model theory. Some of the results of this paper are new.

Keywords

Classical first-order logic

definability

stability

dependence property

coheir

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