摘要
Zhao and Ho asked in a recent paper that for each T_0 space X, whether KB(X)(the set of all irreducible closed sets of X whose suprema exist) is the canonical k-bounded sobrification of X in the sense of Keimel and Lawson. In this paper, we construct a counterexample to give a negative answer. We also consider the subcategory Top_κ of the category Top_0 of T_0 spaces, and prove that the category KBSob of k-bounded sober spaces is a full reflective subcategory of the category Top_κ.
Zhao and Ho asked in a recent paper that for each T_0 space X, whether KB(X)(the set of all irreducible closed sets of X whose suprema exist) is the canonical k-bounded sobrification of X in the sense of Keimel and Lawson. In this paper, we construct a counterexample to give a negative answer. We also consider the subcategory Top_κ of the category Top_0 of T_0 spaces, and prove that the category KBSob of k-bounded sober spaces is a full reflective subcategory of the category Top_κ.
引文
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