N-anti-exchange closure operators
Natural continuity space structures on dual Heyting algebras
Naturality of f-separation axioms
N-compact frames
We investigate notions of -compactness for frames. We find that the analogues of equivalent conditions defining -compact spaces are no longer equivalent in the frame context. Indeed, the closed quotients of frame ‘-cubes’ are exactly 0-dimensional Lindelöf frames, whereas those frames which satisfy a property based on the ultrafilter condition for spatial -compactness form a much larger class, and better embody what ‘-compact frames’ should be. This latter property is expressible without reference...
Near -compactness in -topological spaces.
Neighborhood spaces.
Neighborhood spaces and convergence
Několik příkladů topologických prostorů nesplňujících axiom
Nets and compactness
Network character and tightness of the compact-open topology
For Tychonoff and an infinite cardinal, let the minimum number of cozero-sets of the Čech-Stone compactification which intersect to (generalizing -defect), and let . Give the compact-open topology. It is shown that , where: is tightness; is the network character; is the Lindel"of number. For example, it follows that, for Čech-complete, . The (apparently new) cardinal functions and are compared with several others.
New approach for closure spaces by relations.
New characterizations of regular open sets, semi-regular sets, and extremally disconnectedness
New properties of the concentric circle space and its applications to cardinal inequalities
It is well-known that the concentric circle space has no -diagonal nor any countable point-separating open cover. In this paper, we reveal two new properties of the concentric circle space, which are the weak versions of -diagonal and countable point-separating open cover. Then we introduce two new cardinal functions and sharpen some known cardinal inequalities.
Nilsystèmes d’ordre 2 et parallélépipèdes
En topologie dynamique, une famille classique de systèmes est celle formée par les rotations minimales. La classe des nilsystèmes et de leurs limites projectives en est une extension naturelle. L’étude de ces systèmes est ancienne mais connaît actuellement un renouveau à cause de ses applications, à la fois à la théorie ergodique et en théorie additive des nombres. Les rotations minimales sont caractérisées par le fait que la relation de proximalité régionale est l’égalité. Nous introduisons une...
No upper bound for cardinalities of Tychonoff C.C.C. spaces with a -diagonal exists (an answer to J. Ginsburg and R. G. Woods’ question)
Non Archimedean metric induced fuzzy uniform spaces.
Non-homeomorphic density topologies
Non-isomorphic Hyper-real Fields from Non-isomorphic Ultrapowers.
Nonisomorphic thin-tall superatomic Boolean algebras
Nonlinear mappings in metric discrete limit spaces and their topological properties.