7 papers
Categories of Games and their Fraïssé Theory
Matheus Duzi, Paul Szeptycki, Walter Tholen
Relying on recent generalizations of the Fraïssé theory to a broader category-theoretic context, we study the class of abstract finite games played between two players and show the…
Normality in the square of the Sorgenfrey Line
Paul Szeptycki, Hongwei Wen
We consider sets of reals endowed with the Sorgenfrey lower limit topology denoted . Przymusiński proved that if is a -set then is normal. While t…
Sequentially compact separable spaces
Cesar Corral, Alan Dow, Paul Szeptycki
We consider the following variation of the Scarborough-Stone problem: Is always countably compact whenever is separable and sequentially compact?
Q-Sets, Δ-Sets, and L-Spaces
Pourya Memarpanahi, Paul Szeptycki
The question whether there is a Lindelof Q-set space or Lindelof -set space is considered. We show that J. Moore's ZFC -space is not a Q-set space in ZFC and, assuming all Ar…
High dimensional countable compactness and ultrafilters
Cesar Corral, Pourya Memarpanahi, Paul Szeptycki
We define several notions of a limit point on sequences with domain a barrier in focusing on the two dimensional case . By exploring some natural candidates, we s…
A regular non-weakly discretely generated P-space
Santi Spadaro, Paul Szeptycki
We construct a consistent example of a topological space such that: 1) is regular. 2) Every subset of is open. 3) The point is not isol…
Infinite dimensional sequential compactness: Sequential compactness based on barriers
Cesar Corral, Osvaldo Guzman, Carlos Lopez-Callejas +3
We introduce a generalization of sequential compactness using barriers on extending naturally the notion introduced in [W. Kubiś and P. Szeptycki, On a topological Ramsey theor…