Some combinatorics involving ultrafilters
Some conditions under which a uniform space is fine
Let be a uniform space of uniform weight . It is shown that if every open covering, of power at most , is uniform, then is fine. Furthermore, an -metric space is fine, provided that every finite open covering is uniform.
Some factorization theorems for closed subspaces
Some Generalizations of Lindelöf and Paracompact Spaces.
Some new cardinal inequalities involving a cardinal function less than the spread and the density
Some non-multiplicative properties are -invariant
A cardinal function (or a property ) is called -invariant if for any Tychonoff spaces and with and linearly homeomorphic we have (or the space has () iff ). We prove that the hereditary Lindelöf number is -invariant as well as that there are models of in which hereditary separability is -invariant.
Some non-normal subspaces of the Čech-Stone compactification of a discrete space
Some nowhere densely generated topological properties
Some properties of g- and P-spaces
A γ-space with a strictly positive measure is separable. An example of a non-separable γ−space with c.c.c. is given. A P−space with c.c.c. is countable and discrete.
Some properties related to [a,b]-compactness
Some results on expansions for normal and completely normal spaces.
Some results on inverse spectra. I.
Some results on inverse spectra. II.
Some topological consequences of the Product Measure Extension Axiom
Some types of points in
Spaces in which a bound on cardinality implies discreteness
Spaces with large star cardinal number
In this paper, we prove the following statements: (1) For any cardinal , there exists a Tychonoff star-Lindelöf space such that . (2) There is a Tychonoff discretely star-Lindelöf space such that does not exist. (3) For any cardinal , there exists a Tychonoff pseudocompact -starcompact space such that .
Spaces with zero set bases
Special almost P-spaces
Motivated by some examples, we introduce the concept of special almost P-space and show, using the reflection principle, that for every space of this kind the inequality “" holds.
Strong decomposability of ultrafilters on cardinals with countable cofinality