
In a recent conversation with E. A. Michael and D. Hyman the following natural question was raised: Are the M-spaces of Hyman (see Definition 3.1) metrizable whenever they are first countable? We will answer this question affirmatively. Indeed, we will prove the somewhat stronger result that the M-spaces of Hyman are metrizable whenever they are of pointwise countable type (see Definition 1.1 and ensuing paragraph). It turns out that to answer the preceding question the major difficulty involves the metrizability of adjunction spaces. All our spaces are assumed to be T1.
topology, Metric spaces, metrizability, Adjunction spaces and similar constructions in general topology
topology, Metric spaces, metrizability, Adjunction spaces and similar constructions in general topology
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 2 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
