This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a...This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a first countable T_(0) space is sober if and only if it does not contain a∏_(2)^(0)-subspace homeomorphic either to S_(D),the natural number set equipped with the Scott topology,or to S_(1),the natural number set equipped with the cofinite topology,and it does not contain any directed closed subset without maximal elements either.Second,we show that if Y is sober,the function space TOP(X,Y)equipped with the Isbell topology(respectively,Scott topology)may be a non-sober space.Furthermore,we provide a uniform construction to d-spaces and well-filtered spaces via irreducible subset systems introduced in[9];we called this an H-well-filtered space.We obtain that,for a T_(0) space X and an H-well-filtered space Y,the function space TOP(X,Y)equipped with the Isbell topology is H-well-filtered.Going beyond the aforementioned work,we solve several open problems concerning strong d-spaces posed by Xu and Zhao in[11].展开更多
This paper, using the monads theory in the topological space, gives a new characterization of irreducible sets in the nonstandard enlarged models. Further, the discretization expression of Sober topological spaces is ...This paper, using the monads theory in the topological space, gives a new characterization of irreducible sets in the nonstandard enlarged models. Further, the discretization expression of Sober topological spaces is presented.展开更多
对拓扑空间的sober分离性细致分析后引入类似于sober性的另外两种分离性:仿sober和超sober分离性;讨论了诸分离性的相关性质和相互关系,证明了非T1的仿sober空间一定是连通的、可分的sober空间;还探讨了dom a in上Scott拓扑与仿sober、...对拓扑空间的sober分离性细致分析后引入类似于sober性的另外两种分离性:仿sober和超sober分离性;讨论了诸分离性的相关性质和相互关系,证明了非T1的仿sober空间一定是连通的、可分的sober空间;还探讨了dom a in上Scott拓扑与仿sober、超sober分离性的关系,证明了仿(超)sober偏序集均为代数dom a in.展开更多
文摘This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a first countable T_(0) space is sober if and only if it does not contain a∏_(2)^(0)-subspace homeomorphic either to S_(D),the natural number set equipped with the Scott topology,or to S_(1),the natural number set equipped with the cofinite topology,and it does not contain any directed closed subset without maximal elements either.Second,we show that if Y is sober,the function space TOP(X,Y)equipped with the Isbell topology(respectively,Scott topology)may be a non-sober space.Furthermore,we provide a uniform construction to d-spaces and well-filtered spaces via irreducible subset systems introduced in[9];we called this an H-well-filtered space.We obtain that,for a T_(0) space X and an H-well-filtered space Y,the function space TOP(X,Y)equipped with the Isbell topology is H-well-filtered.Going beyond the aforementioned work,we solve several open problems concerning strong d-spaces posed by Xu and Zhao in[11].
基金Supported by the Natural Science Foundation of Shaanxi Province(2007A12) Supported by the Scientific Research Foundation of Shaanxi Educational Committee(11JK0507)
文摘This paper, using the monads theory in the topological space, gives a new characterization of irreducible sets in the nonstandard enlarged models. Further, the discretization expression of Sober topological spaces is presented.
文摘对拓扑空间的sober分离性细致分析后引入类似于sober性的另外两种分离性:仿sober和超sober分离性;讨论了诸分离性的相关性质和相互关系,证明了非T1的仿sober空间一定是连通的、可分的sober空间;还探讨了dom a in上Scott拓扑与仿sober、超sober分离性的关系,证明了仿(超)sober偏序集均为代数dom a in.