6 papers
Projective -character bounds the order of a -base
Istvan Juhasz, Zoltan Szentmiklossy
All spaces below are Tychonov. We define the projective pi-character p(X) of a space X as the supremum of the values where Y ranges over all continuous images of X. Our mai…
First countable spaces without point-countable -base
Istvan Juhasz, Lajos Soukup, Zoltan Szentmiklossy
We answer several questions of V. Tkačuk from [Point-countable -bases in first countable and similar spaces, Fund. Math. 186 (2005), pp. 55--69.] by showing that (1) there is a…
Resolvability vs. almost resolvability
Istvan Juhasz, Saharon Shelah, Lajos Soukup
A space X is kappa-resolvable (resp. almost kappa-resolvable) if it contains kappa dense sets that are pairwise disjoint (resp. almost disjoint over the ideal of nowhere dense subs…
Lindelof spaces of singular density
Istvan Juhasz, Saharon Shelah
A cardinal lambda is called omega-inaccessible if for all mu < lambda we have mu^omega<lambda. We show that for every omega-inaccessible cardinal lambda there is a CCC (hence cardi…
Characterizing continuity by preserving compactness and connectedness
Janos Gerlits, Istvan Juhasz, Lajos Soukup +1
Let us call a function from a space into a space preserving if the image of every compact subspace of is compact in and the image of every connected subspace of…
Strongly almost disjoint families, II
Andras Hajnal, Istvan Juhasz, Saharon Shelah
The relations M(kappa,lambda,mu)->B [resp. B(sigma)] meaning that if A subset [kappa]^lambda with |A|=kappa is mu-almost disjoint then A has property B [resp. has a sigma-transvers…