The main aim of this paper is to give a simpler proof of the following assertion. Let A be an analytic non-σ-porous subset of a locally compact metric space, E. Then there exists a compact non-σ-porous subset of A. Moreover, we prove the above assertion also for σ-P-porous sets, where P is a porosity-like relation on E satisfying some additional conditions. Our result covers σ-⟨g⟩-porous sets, σ-porous sets, and σ-symmetrically porous sets.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-fm185-1-2, author = {Miroslav Zelen\'y and Lud\v ek Zaj\'\i \v cek}, title = {Inscribing compact non-$\sigma$-porous sets into analytic non-$\sigma$-porous sets}, journal = {Fundamenta Mathematicae}, volume = {185}, year = {2005}, pages = {19-39}, zbl = {1086.54025}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-fm185-1-2} }
Miroslav Zelený; Luděk Zajíček. Inscribing compact non-σ-porous sets into analytic non-σ-porous sets. Fundamenta Mathematicae, Tome 185 (2005) pp. 19-39. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-fm185-1-2/