In a left-topological semigroup with dense center the closure of any left ideal is an ideal.
Induced measures on Wallman spaces.
Involutions on the second duals of group algebras versus subamenable groups
Let L¹(G)** be the second dual of the group algebra L¹(G) of a locally compact group G. We study the question of involutions on L¹(G)**. A new class of subamenable groups is introduced which is universal for all groups. There is no involution on L¹(G)** for a subamenable group G.
La complétion universelle d'un produit d'espaces complètement réguliers
Linear equations in the Stone-Čech compactification of .
Local cardinal functions of H-closed spaces
The cardinal functions of pseudocharacter, closed pseudocharacter, and character are used to examine H-closed spaces and to contrast the differences between H-closed and minimal Hausdorff spaces. An H-closed space is produced with the properties that and .
Local/global uniform approximation of real-valued continuous functions
For a Tychonoff space , is the lattice-ordered group (-group) of real-valued continuous functions on , and is the sub--group of bounded functions. A property that might have is (AP) whenever is a divisible sub--group of , containing the constant function 1, and separating points from closed sets in , then any function in can be approximated uniformly over by functions which are locally in . The vector lattice version of the Stone-Weierstrass Theorem is more-or-less equivalent...
Locally compact spaces whose Alexandroff one-point compactifications are perfect
Locally fine uniformities and normal covers
ℓp-Movable At Infinity Spaces, Compact And Divisors And Property UVWn
Maximal ideals in the Lie algebra of vector fields
Measure and measurable functions of
Minimal ideals and cancellation in ßN.
More on tie-points and homeomorphism in ℕ*
A point x is a (bow) tie-point of a space X if X∖x can be partitioned into (relatively) clopen sets each with x in its closure. We denote this as where A, B are the closed sets which have a unique common accumulation point x. Tie-points have appeared in the construction of non-trivial autohomeomorphisms of βℕ = ℕ* (by Veličković and Shelah Steprans) and in the recent study (by Levy and Dow Techanie) of precisely 2-to-1 maps on ℕ*. In these cases the tie-points have been the unique fixed point...
More on -Ohio completeness
We study closed subspaces of -Ohio complete spaces and, for uncountable cardinal, we prove a characterization for them. We then investigate the behaviour of products of -Ohio complete spaces. We prove that, if the cardinal is endowed with either the order or the discrete topology, the space is not -Ohio complete. As a consequence, we show that, if is less than the first weakly inaccessible cardinal, then neither the space , nor the space is -Ohio complete.
Mutually compactificable topological spaces.
Natural sinks on
Let be the large source of epimorphisms in the category of Urysohn spaces constructed in [2]. A sink is called natural, if for all . In this paper natural sinks are characterized. As a result it is shown that permits no -factorization structure for arbitrary (large) sources.
Non existence de relèvement pour certaines mesures finiement additives et retractés de ...N.
Non-accessible points in extremally disconnected compact spaces I