Fan recognition from common-vertex arc decompositions in 1-dimensional continua
Determine whether every 1-dimensional continuum X that can be written as the union of a family of arcs {L} whose pairwise intersections are exactly a single common point v (that is, there exists v in X and a collection of arcs L with X = ⋃L and L ∩ L' = {v} for all distinct L, L' in L) must necessarily satisfy that the intersection of any two subcontinua of X is connected; equivalently, determine whether every such X is a fan.
References
It is an open question as to whether every $1$-dimensional continuum that satisfies (1) is a fan Problem 3.4.
— On a local property of fences and fans
(2508.03530 - Lipham, 5 Aug 2025) in Section 1 (Introduction)