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Topological structure of the hyperspace of full-dimensional closed convex subsets of R^n with the Fell topology

Determine the topological structure (e.g., homeomorphism type or a complete classification) of the hyperspace (K_n, TF), where K_n denotes the subspace of K^n consisting of all closed convex subsets of R^n whose affine hull has dimension n (equivalently, closed convex subsets with nonempty interior), and TF denotes the Fell topology.

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Background

The paper studies hyperspaces of closed convex subsets of a Hilbert space, focusing on finite-dimensional Euclidean spaces Rn. It uses several hyperspace topologies, notably the Fell topology (TF) and the Attouch–Wets topology, and analyzes subspaces defined by dimension.

Let Kn be the hyperspace of all nonempty closed convex subsets of Rn, and K_n the subspace of those with full affine dimension n (i.e., nonempty interior). While it is known that (Kn, TF) is homeomorphic to Rn × Q (where Q is the Hilbert cube), the precise topological type of (K_n, TF) is not established in the literature.

In this paper, Proposition 2.11 shows that (K_n, TF) is an open subspace of (Kn, TF) and thus a Q-manifold. However, the authors explicitly note that the overall topological structure of (K_n, TF) remains unknown, indicating a gap in the current classification beyond the Q-manifold property.

References

As far as we know, the topology structure of the hyperspace Kn (equipped with the Fell topology) is unknown.

The hyperspace of k-dimensional closed convex sets (2410.00839 - Escobedo-Bustamante et al., 1 Oct 2024) in Section 2.3 (Q-manifolds), preceding Proposition 2.11