A few topological problems
A game and its relation to netweight and D-spaces
We introduce a two player topological game and study the relationship of the existence of winning strategies to base properties and covering properties of the underlying space. The existence of a winning strategy for one of the players is conjectured to be equivalent to the space have countable network weight. In addition, connections to the class of D-spaces and the class of hereditarily Lindelöf spaces are shown.
A lattice of conditions on topological spaces II
A note about -spaces and stratifiable spaces
A note on k-c-semistratifiable spaces and strong -spaces
Recall that a space is a c-semistratifiable (CSS) space, if the compact sets of are -sets in a uniform way. In this note, we introduce another class of spaces, denoting it by k-c-semistratifiable (k-CSS), which generalizes the concept of c-semistratifiable. We discuss some properties of k-c-semistratifiable spaces. We prove that a -space is a k-c-semistratifiable space if and only if has a function which satisfies the following conditions: (1) For each , and for each . (2) If a...
A note on monotone countable paracompactness
We show that a space is MCP (monotone countable paracompact) if and only if it has property , introduced by Teng, Xia and Lin. The relationship between MCP and stratifiability is highlighted by a similar characterization of stratifiability. Using this result, we prove that MCP is preserved by both countably biquotient closed and peripherally countably compact closed mappings, from which it follows that both strongly Fréchet spaces and q-space closed images of MCP spaces are MCP. Some results on...
A remark on the weak topology of the Hilbert space
Another generalization of the Dugundji extension theorem
Characterizations of -stratifiable spaces
Characterizations of σ-spaces
Concerning certain minimal cover refineable spaces
Convexité topologique et prolongement des fonctions continues
Correction to the paper: Pairwise monotonically normal spaces
Correction to the paper: Sets invariant under projections onto one dimensional subspaces
Decreasing (G) spaces
We consider the class of decreasing (G) spaces introduced by Collins and Roscoe and address the question as to whether it coincides with the class of decreasing (A) spaces. We provide a partial solution to this problem (the answer is yes for homogeneous spaces). We also express decreasing (G) as a monotone normality type condition and explore the preservation of decreasing (G) type properties under closed maps. The corresponding results for decreasing (A) spaces are unknown.
Direct sums of stratifiable spaces
Equiconnected spaces and Baire classification of separately continuous functions and their analogs
We investigate the Baire classification of mappings f: X × Y → Z, where X belongs to a wide class of spaces which includes all metrizable spaces, Y is a topological space, Z is an equiconnected space, which are continuous in the first variable. We show that for a dense set in X these mappings are functions of a Baire class α in the second variable.
Hyperspaces of CW-complexes
It is shown that the hyperspace of a connected CW-complex is an absolute retract for stratifiable spaces, where the hyperspace is the space of non-empty compact (connected) sets with the Vietoris topology.
Les stratifiés topologiques et les polyèdres
On conjecture que certains espaces localement étoilés admettent toujours une jolie stratification naturelle, et deviennent ainsi ce qu’on appelle des ensembles. On cite quelques propriétés agréables des ensembles, et quelques exemples exotiques qui distinguent les ensembles, les espaces triangulables, et les espaces localement triangulables.
Metrizability, generalized metric spaces and -functions