Some Results on G-Delta Ideals of Compact Sets

Abstract

For a compact metric space E, Solecki has defined a broad natural class of Gdelta ideals of compact sets on E, called Gdelta ideals with property (*), and has shown that any ideal I in this class can be represented through the ideal of nowhere dense subsets of a closed subset F of the hyperspace of compact subsets of E. In this thesis we show that the closed set F in this representation can be taken to be closed upwards, i.e., it contains the compact supersets of its members. We examine the behaviour of Gdelta subsets of E with respect to the representing sets of I; we formulate a conjecture and prove it for several classes of ideals.