Quasi -compact spaces
Quasicontinuous spaces
We lift the notion of quasicontinuous posets to the topology context, called quasicontinuous spaces, and further study such spaces. The main results are: (1) A space is a quasicontinuous space if and only if is locally hypercompact if and only if is a hypercontinuous lattice; (2) a space is an -continuous space if and only if is a meet continuous and quasicontinuous space; (3) if a -space is a well-filtered poset under its specialization order, then is a quasicontinuous space...
Quasi-metrizable spaces with a bicomplete structure.
Quasi-metrization and hereditary normality of compact bitopological spaces
Quasi-orbit spaces associated to T₀-spaces
Let G ⊂ Homeo(E) be a group of homeomorphisms of a topological space E. The class of an orbit O of G is the union of all orbits having the same closure as O. Let E/G̃ be the space of classes of orbits, called the quasi-orbit space. We show that every second countable T₀-space Y is a quasi-orbit space E/G̃, where E is a second countable metric space. The regular part X₀ of a T₀-space X is the union of open subsets homeomorphic to ℝ or to 𝕊¹. We give a characterization of the spaces X with finite...
Quasi-radicals and Radicals in Categories
Quasiregular rings
Quasi-uniform completions of partially ordered spaces
Quelques résultats nouveaux sur les points extrémaux d'un simplexe compact
Quotients of indecomposable Banach spaces of continuous functions
Assuming ⋄, we construct a connected compact topological space K such that for every closed L ⊂ K the Banach space C(L) has few operators, in the sense that every operator on C(L) is multiplication by a continuous function plus a weakly compact operator. In particular, C(K) is indecomposable and has continuum many non-isomorphic indecomposable quotients, and K does not contain a homeomorphic copy of βℕ. Moreover, assuming CH we construct a connected compact K where C(K) has few...
Quotients of k-semigroups.
and axioms in fuzzy topology
-continuous functions.
-compact spaces and -connected spaces.
Radical ideals and coherent frames
It follows from Stone Duality that Hochster's results on the relation between spectral spaces and prime spectra of rings translate into analogous, formally stronger results concerning coherent frames and frames of radical ideals of rings. Here, we show that the latter can actually be obtained without Stone Duality, proving them in Zermelo-Fraenkel set theory and thereby sharpening the original results of Hochster.
Radon spaces which are not -fragmentable
Ramsey theoretic consequences of some new results about algebra in the Stone-Čech compactification.
Rapid ultrafilter need not be Q-point
Rapport entre l'ensemble des ultrafiltres admettant un ultrafiltre donné pour image et l'ensemble des images de cet ultrafiltre
Rare -continuity.