Connected union with a connected hub

ID: connected-union-with-a-connected-hub

Suppose connected subsets all meet one connected member . A separation of their union would place entirely on one side. Each is also entirely on one side and intersects , so every lies on the same side, contradicting nonempty separation. Thus the union is connected. If the subsets are path-connected, join two points by a path to , a path inside , and a path back out. This needs pairwise contact with the hub, not one point shared by every subset.

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