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Prime Ends and Local Connectivity

Lasse Rempe-Gillen
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Abstract

Let U be a simply connected domain on the Riemann sphere whose complement K contains more than one point. We establish a characterization of local connectivity of K at a point in terms of the prime ends whose impressions contain this point. Invoking a result of Ursell and Young, we obtain an alternative proof of a theorem of Torhorst, which states that the impression of a prime end of $U$ contains at most two points at which $K$ is locally connected.

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Lasse Rempe-Gillen. 2014-02-19. Prime Ends and Local Connectivity. https://doi.org/10.1112/blms%2Fbdn061

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