Optimal quasi-metrics in a given pointwise equivalence class do not always exist

In this paper we provide an answer to a question found in [3], namely when given a quasi-metric p, if one examines all quasi-metrics which are pointwise equivalent to p, does there exist one which is most like an ultrametric (or, equivalently, exhibits an optimal amount of Hölder regularity)? The an...

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Detalles Bibliográficos
Autores: Brigham, Dan, Mitrea, Marius
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:133144
Acceso en línea:https://ddd.uab.cat/record/133144
https://dx.doi.org/urn:doi:10.5565/PUBLMAT_59215_08
Access Level:acceso abierto
Palabra clave:F-norm
Holder regularity
Minkowski functional
Metrization theorem
Metrizing quasi-modular
Modulus of concavity
Quasi-metric, quasi-norm
Rolewicz-orlicz space
Topological vector space
Descripción
Sumario:In this paper we provide an answer to a question found in [3], namely when given a quasi-metric p, if one examines all quasi-metrics which are pointwise equivalent to p, does there exist one which is most like an ultrametric (or, equivalently, exhibits an optimal amount of Hölder regularity)? The answer, in general, is negative, which we demonstrate by constructing a suitable Rolewicz-Orlicz space.