Topologies Generated by Discrete Subspaces

نویسندگان

  • A. Dow
  • M. G. Tkachenko
  • V. V. Tkachuk
  • R. G. Wilson
  • M. G. TKACHENKO
  • V. V. TKACHUK
  • R. G. WILSON
چکیده

A topological space X is called discretely generated if for every subset A⊂X we have A=∪{D:D⊂A and D is a discrete subspace of X}. We say that X is weakly discretely generated if A⊂X and A6=A implies D\A6=∅ for some discrete D⊂A. It is established that sequential spaces, monotonically normal spaces and compact countably tight spaces are discretely generated. We also prove that every compact space is weakly discretely generated and under the Continuum Hypothesis any dyadic discretely generated space is metrizable.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Topologies Induced by Relations with Applications

Some methods for inducing topological structures by relations were initiated and their importance in applications were indicated. Topologies generated by equivalence relations were all quasi-discrete spaces. We induced the topologies generated using similarity relations and pre-order relations. Also, the topologies generated using general binary relations on the universe of discourse were initi...

متن کامل

Preorder Relators and Generalized Topologies

In this paper we investigate generalized topologies generated by a subbase of preorder relators and consider its application in the concept of the complement. We introduce the notion of principal generalized topologies obtained from the new type of open sets and study some of their important properties.

متن کامل

Further study on $(L,M)$-fuzzy topologies and $(L,M)$-fuzzy neighborhood systems

Following the idea of $L$-fuzzy neighborhood system as introduced byFu-Gui Shi, and its generalization to $(L,M)$-fuzzy neighborhood system, the relationship between  $(L,M)$-fuzzy topology and $(L,M)$-fuzzy neighborhood system will be further studied. As an application of the obtained results, we will describe the initial structures of $(L,M)$-fuzzy neighborhood subspaces and $(L,M)$-fuzzy top...

متن کامل

On the density of the minimal subspaces generated by discrete linear Hamiltonian systems

This paper focuses on the density of the minimal subspaces generated by a class of discrete linear Hamiltonian systems. It is shown that the minimal subspace is densely defined if and only if the maximal subspace is an operator; that is, it is single valued. In addition, it is shown that, if the interval on which the systems are defined is bounded from below or above, then the minimal subspace ...

متن کامل

Efficient hexapodal locomotion control based on flow-invariant subspaces

In this paper the issue of locomotion control in bio-inspired hexapod structures is considered as a problem of convergence toward flow invariant subspaces in networks of mutually and locally coupled neural units. Since the network topologies used refer to undirected diffusive tree graphs, in this case a unique gain value on the graph connection matrix can be found to guarantee exponential conve...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2014