<p>The purpose of this article is to study and investigate e<sub>c</sub>-filters on X and e<sub>c</sub>-ideals in C<sup>*</sup><sub>c </sub>(X) in which they are in fact the counterparts of z<sub>c</sub>-filters on X and z<sub>c</sub>-ideals in C<sub>c</sub>(X) respectively. We show that the maximal ideals of C<sup>*</sup><sub>c </sub>(X) are in one-to-one correspondence with the e<sub>c</sub>-ultrafilters on X. In addition, the sets of e<sub>c</sub>-ultrafilters and z<sub>c</sub>-ultrafilters are in one-to-one correspondence. It is also shown that the sets of maximal ideals of C<sub>c</sub>(X) and C<sup>*</sup><sub>c </sub>(X) have the same cardinality. As another application of the new concepts, we characterized maximal ideals of C<sup>*</sup><sub>c </sub>(X). Finally, we show that whether the space X is compact, a proper ideal I of C<sub>c</sub>(X) is an e<sub>c</sub>-ideal if and only if it is a closed ideal in C<sub>c</sub>(X) if and only if it is an intersection of maximal ideals of C<sub>c</sub>(X).</p>
In this paper, closed ideals in Cc(X), the functionally countable subalgebra of C(X), with the mc-topology, is studied. We show that ifX is CUC-space, then C*c(X) with the uniform norm-topology is a Banach algebra. Closed ideals in Cc(X) as a modified countable analogue of closed ideals in C(X) with the m-topology are characterized. For a zero-dimensional space X, we show that a proper ideal in Cc(X) is closed if and only if it is an intersection of maximal ideals of Cc(X). It is also shown that every ideal in Cc(X) with the mc-topology is closed if and only if X is a P-space if and only if every ideal in C(X) with the m-topology is closed. Moreover, for a strongly zero-dimensional space X, it is proved that a properly closed ideal in C*c(X) is an intersection of maximal ideals of C*c(X) if and only if X is pseudo compact. Finally, we show that if X is a P-space and F is an ec-filter on X, then F is an ec-ultrafilter if and only if it is a zc-ultrafilter.
<p>When working with a metric space, we are dealing with the additive group (R, +). Replacing (R, +) with an Abelian group (G, ∗), offers a new structure of a metric space. We call it a G-metric space and the induced topology is called the G-metric topology. In this paper, we are studying G-metric spaces based on L-groups (i.e., partially ordered groups which are lattices). Some results in G-metric spaces are obtained. The G-metric topology is defined which is further studied for its topological properties. We prove that if G is a densely ordered group or an infinite cyclic group, then every G-metric space is Hausdorff. It is shown that if G is a Dedekind-complete densely ordered group, (X, d) a G-metric space, A ⊆ X and d is bounded, then f : X → G with f(x) = d(x, A) := inf{d(x, a) : a ∈ A} is continuous and further x ∈ cl<sub>X</sub>A if and only if f(x) = e (the identity element in G). Moreover, we show that if G is a densely ordered group and further a closed subset of R, K(X) is the family of nonempty compact subsets of X, e < g ∈ G and d is bounded, then d′ (A, B) < g if and only if A ⊆ N<sub>d</sub>(B, g) and B ⊆ N<sub>d</sub>(A, g), where N<sub>d</sub>(A, g) = {x ∈ X : d(x, A) < g}, d<sub>B</sub>(A) = sup{d(a, B) : a ∈ A} and d′ (A, B) = sup{d<sub>A</sub>(B), d<sub>B</sub>(A)}.</p>
For a zero-dimensional topological space X and a totally ordered field F with interval topology, Cc(X, F) denotes the ring consisting of ordered field-valued continuous functions with countable range on X. This article aims to study and investigate the rings of quotients of Cc(X,F). Qc(X,F) (resp. qc(X,F)), the maximal (resp. classical) ring of quotients of Cc(X,F) as a modified countable analogue of Q(X) (resp. q(X)), the maximal (resp. classical) ring of quotients of C(X) are characterized. It is proved that Qc(S), the maximal ring of quotients of the subring S of Cc(X,F), is a subring of Qc(X, F) if and only if every dense ideal in S has dense cozero-set in X. Also, the coincidence of rings of quotients of Cc(X, F) is investigated. We show that qc(X,F)=Cc(X, F) if and only if the set of non-units and zero-divisors in Cc(X,F) coincide if and only if X is almost CPF-space. Finally, it is shown that the fixed ring of quotients and the cofinite ring of quotients of Cc(X) coincide if and only if Hom(Mcp) = Cc(Xp) for every p ? X.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.