{ "id": "2009.13273", "version": "v1", "published": "2020-09-28T13:03:14.000Z", "updated": "2020-09-28T13:03:14.000Z", "title": "Metric Segments in Gromov--Hausdorff class", "authors": [ "Olga Borisova" ], "categories": [ "math.GN" ], "abstract": "We study properties of metric segments in the class of all metric spaces considered up to an isometry, endowed with Gromov--Hausdorff distance. On the isometry classes of all compact metric spaces, the Gromov-Hausdorff distance is a metric. A metric segment is a class that consists of points lying between two given ones. By von Neumann--Bernays--G\\\"odel (NBG) axiomatic set theory, a proper class is a \"monster collection\", e.g., the collection of all cardinal sets. We prove that any metric segment in the proper class of isometry classes of all metric spaces with the Gromov-Hausdorff distance is a proper class if the segment contains at least one metric space at positive distances from the segment endpoints. In addition, we show that the restriction of a non-degenerated metric segment to compact metric spaces is a non-compact set.", "revisions": [ { "version": "v1", "updated": "2020-09-28T13:03:14.000Z" } ], "analyses": { "keywords": [ "gromov-hausdorff class", "gromov-hausdorff distance", "compact metric spaces", "proper class", "isometry classes" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }