Products with Linear and Countable Type Factors
نویسندگان
چکیده
The basic theorem presented shows that the product of a linearly ordered space and a countable (regular) space is normal. We prove that the countable space can be replaced by any of a rather large class of countably tight spaces. Examples are given to prove that monotone normality cannot replace linearly ordered in the base theorem. However, it is shown that the product of a monotonically normal space and a monotonically normal countable space is
منابع مشابه
Iterative methods for finding nearest common fixed points of a countable family of quasi-Lipschitzian mappings
We prove a strong convergence result for a sequence generated by Halpern's type iteration for approximating a common fixed point of a countable family of quasi-Lipschitzian mappings in a real Hilbert space. Consequently, we apply our results to the problem of finding a common fixed point of asymptotically nonexpansive mappings, an equilibrium problem, and a variational inequality problem for co...
متن کاملm at h . FA ] 2 6 O ct 1 99 3 ON COMPLEMENTED SUBSPACES OF SUMS AND PRODUCTS OF BANACH SPACES
It is proved that there exist complemented subspaces of countable topo-logical products (locally convex direct sums) of Banach spaces which cannot be represented as topological products (locally convex direct sums) of Banach spaces The problem of description of complemented subspaces of a given locally convex space is one of the general problems of structure theory of locally convex spaces. In ...
متن کاملCountable Compactiications and a Generalized Hahn-mazurkiewicz Type Theorem
In this paper, we provide a characterization as to when a locally connected generalized continuum (a locally compact connected separable metric space) has a countable compactiication of a certain order type. We then prove that for any two locally connected generalized continua with maximal countable compactiications X and Y of the same order type there is a perfect surjection f : X ! Y. This pr...
متن کاملLexicographic semigroupoids
The natural lexicographic semigroupoids associated with Cantor product spaces indexed by countable linear orders are classified. Applications are given to the classification of triangular operator algebras which are direct limits of upper-triangular matrix algebras. 0. Introduction Consider a Cantor space which is presented explicitly as an infinite product of finite topological spaces. The pro...
متن کاملGo-spaces and Noetherian Spectra
The Noetherian type of a space is the least κ for which the space has a κop-like base, i.e., a base in which no element has κ-many supersets. We prove some results about Noetherian types of (generalized) ordered spaces and products thereof. For example: the density of a product of not-too-many compact linear orders never exceeds its Noetherian type, with equality possible only for singular Noet...
متن کامل