由度量空间诱导的*-拓扑和s-拓扑(* -Topology and s-topology induced by metric space)

Abstract

This paper studies * -topology and s-topology in polysaturated nonstandard model,which are induced by metric space on two nonstandard sets. In order to construct * -topology , the set of finite points is introduced. It shows that every internal set is compact, every open set is saturated and standard part mapping is continuous. Finally,the closure operator,interior operator and mapping * are discussed under s-topology .

Keywords

• finite point
• saturated set
• standard part mapping
• functor