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Equality of π”ˆ(b_r G) and e_{c_m X}G for ultrahomogeneous LOTS

Determine whether the equality π”ˆ(b_r G) = e_{c_m X}G holds for G = Aut(X) with the topology of pointwise convergence Ο„_p acting on an ultrahomogeneous linearly ordered topological space X, where b_r G is the Roelcke compactification of G and c_m X is the least linearly ordered compactification of X.

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Background

Theorem β€˜Roelcke precomp4-3-1’ establishes that for an ultrahomogeneous LOTS X, the Ellis compactification e_{c_m X}G is the completion of (G, R_{Ξ£{c_m X}}), that G is Roelcke precompact, and that b_r G < e{c_m X}G. The map π”ˆ is defined earlier as sending a G-compactification of G to the corresponding Ellis compactification.

The authors ask if applying π”ˆ to the Roelcke compactification b_r G yields precisely the Ellis compactification e_{c_m X}G obtained from the maximal linearly ordered compactification c_m X. Resolving this would clarify the precise relationship between the Roelcke and Ellis compactifications in the ultrahomogeneous LOTS setting.

References

Question. Is the equality π”ˆ (b_r G) = e_{c_m X} G valid?

Enveloping semigroups as compactifications of topological groups (2509.17577 - Kozlov et al., 22 Sep 2025) in Question, Section 6.2 (Ellis compactifications of the automorphism group of ultrahomogeneous LOTS), after Theorem β€˜Roelcke precomp4-3-1’