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Do barycenters of convex sets lie inside the set in RCD(0,N) spaces?

Determine whether, in an RCD(0,N) metric measure space with N in (1,∞), for any convex set Ω with finite measure, every barycenter of the uniform probability measure on Ω belongs to Ω (i.e., lies inside the convex set).

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Background

The paper generalizes Grünbaum’s inequality to RCD(0,N) spaces and discusses barycenters defined via minimization of second-moment-type functionals for probability measures. For uniform measures on convex sets in Euclidean spaces, the barycenter (centroid) lies in the set, but in RCD(0,N) spaces barycenters may be non-unique.

The authors provide an example (a cylinder R × S1 with Ω = [-1,1] × S1) where many barycenters exist, all lying on {0} × S1, and note uncertainty about whether barycenters always lie in Ω in general.

References

It seems unclear (to the authors) if every barycenter of Ω lives in Ω.

A generalization of Grünbaum's inequality in RCD$(0,N)$-spaces (2408.15030 - Brunel et al., 27 Aug 2024) in Section 1 (Introduction), following Corollary 1 (Main results)