3 papers
math.GN2025
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…
math.GN2024
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…
math.GN2023
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…