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Converse transfer of ultrafilter orders from a chainable continuum to its inverse-limit model

Determine whether, for every chainable continuum X that is homeomorphic to an inverse limit of arcs Y = lim←(I_i,f_i)_{i=1}^∞, every ultrafilter order ≤_U^D on X (defined via a sequence of chains D covering X with mesh(D_n) → 0 and a non-principal ultrafilter U on ℕ) arises from some ultrafilter order ≤_U^{(I_i,f_i)_{i=1}^∞} on Y in the sense that there exists a homeomorphism h': X → Y with x ≤_U^D y if and only if h'(x) ≤_U^{(I_i,f_i)_{i=1}^∞} h'(y).

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Background

The paper introduces two constructions of ultrafilter orders on chainable continua: one using sequences of increasingly fine chains (Definition 3.1) and another using inverse limits of arcs (Definition 3.7). Theorem 3 (Transfer) shows that any ultrafilter order defined on the inverse limit Y induces an ultrafilter order on the homeomorphic chainable continuum X.

The authors explicitly note that the reverse direction is unknown: whether any ultrafilter order defined via chains on X can be represented as one coming from the inverse-limit construction on Y under a homeomorphism, thus making the two approaches fully equivalent.

References

Thus we have proved that any ultrafilter order on Y generates an ultrafilter order on X. However we don't know if the converse holds, i.e. if it is true that for a chainable continuum X and for the inverse limit of a sequence of arcs Y, homeomorphic to X, any ultrafilter order on X generates some ultrafilter order on Y (see Question \ref{two_approaches}).

Linear orders on chainable continua (2510.14577 - Marciszewski et al., 16 Oct 2025) in Section 3 (Definitions of ultrafilter orders and some of their basic properties), after Theorem 3 (Transfer)