Abstract
We show that if \((X,d)\) is a metric space which admits a consistent convex geodesic bicombing, then we can construct a conical bicombing on \(CB(X)\), the hyperspace of nonempty, closed, bounded, and convex subsets of \(X\) (with the Hausdorff metric). If \(X\) is a normed space or an \(\mathbb {R}\)-tree, this same method produces a consistent convex bicombing on \(CB(X)\). We follow this by examining a geodesic bicombing on the nonempty compact subsets of \(X\), assuming \(X\) is a proper metric space.
Similar content being viewed by others
Notes
Other authors may call this \(\sigma \)-convex, as it does in fact depend on the bicombing \(\sigma \).
Every complete and locally compact space with intrinsic metric is a proper geodesic space.
References
Basso, G., Miesch, B.: Conical geodesic bicombings on subsets of normed vector spaces. Adv. Geom. 19(2), 151–164 (2019)
Beer, G..: Topologies on closed and closed convex sets. Kluwer Academic Publishers, (1993)
Martin, R.: Bridson and André Haefliger. Springer, Berlin (1999)
Descombes, D..: Spaces with Convex Geodesic Bicombings. PhD thesis, ETH Zürich, (2015)
Descombes, D., Lang, U.: Convex geodesic bicombings and hyperbolicity. Geom. Dedicata. 177, 367–384 (2015)
Hörmander, L.: Sur la fonction d’appui des ensembles convexes dans un espace localement convexe. Ark. Mat. 3(12), 181–186 (1954)
Ibragimov, Z.: Hyperbolizing hyperspaces. Michigan Math. J. 60, 215–239 (2011)
Michael, E.: Topologies on spaces of subsets. Trans. Am. Math. Soc. 71, 152–182 (1951)
Morgan, J.W., Shalen, P.B.: Valuations, trees, and degenerations of hyperbolic structures I. Ann. Math. 120(3), 401–476 (1984)
Sosov, E.N.: On Hausdorff intrinsic metric. Lobachevskii J. Math. 8, 185–189 (2001)
Acknowledgements
The author would like to thank Peter Oberly, Joel H.Shapiro, and J.J.P. Veerman for many helpful comments.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The author declares no conflict of interest.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Fox, L.S. Geodesic bicombings on some hyperspaces. J. Geom. 113, 28 (2022). https://doi.org/10.1007/s00022-022-00642-6
Received:
Revised:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00022-022-00642-6