Descriptive set theory: Difference between revisions

Revision as of 03:51, 23 January 2008

Revision as of 18:19, 25 January 2008

Line 3:

== Polish spaces ==

Descriptive set theory begins with the study of Polish spaces and their [[Borel setsset]]s.

A '''[[Polish space]]''' is a [[second countable]] [[topological space]] that is [[metrizable]] with a [[complete metric]]. Equivalently, it is a complete separable metric space from which the metric has been "forgotten". Examples include the [[real line]], the [[Baire space]], the [[Cantor space]], and the [[Hilbert cube]].