Abstract
Zhao and Ho asked in a recent paper that for each T0 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 Topκ of the category Top0 of T0 spaces, and prove that the category KBSob of k-bounded sober spaces is a full reflective subcategory of the category KBSob of k-bounded sober spaces is a full reflective subcategory of the category Topκ.
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The authors would like to thank the anonymous referees for their valuable comments and suggestions.
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Supported by the National Natural Science Foundation of China (Grant Nos. 11531009 and 11871320) and the Fundamental Research Funds for the Central Universities (Grant No. GK201803002)
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Zhao, B., Lu, J. & Wang, K.Y. The Answer to a Problem Posed by Zhao and Ho. Acta. Math. Sin.-English Ser. 35, 438–444 (2019). https://doi.org/10.1007/s10114-018-7535-6
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DOI: https://doi.org/10.1007/s10114-018-7535-6