Strict rearrangement inequalities: Nonexpansivity and periodic Gagliardo seminorms

This paper deals with the behavior of the periodic Gagliardo seminorm under two types of rearrangements, namely under a periodic, and respectively a cylindrical, symmetric decreasing rearrangement. Our two main results are Pólya-Szego type inequalities for these rearrangements. We also deal with the...

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Bibliographic Details
Authors: Csato, Gyula, Mas Blesa, Albert|||0000-0002-8322-1663
Format: article
Publication Date:2025
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/449141
Online Access:https://hdl.handle.net/2117/449141
https://dx.doi.org/10.1090/tran/9510
Access Level:Open access
Keyword:Àrees temàtiques de la UPC::Matemàtiques i estadística::Equacions diferencials i integrals::Equacions en derivades parcials
Àrees temàtiques de la UPC::Matemàtiques i estadística::Anàlisi matemàtica::Anàlisi funcional
Description
Summary:This paper deals with the behavior of the periodic Gagliardo seminorm under two types of rearrangements, namely under a periodic, and respectively a cylindrical, symmetric decreasing rearrangement. Our two main results are Pólya-Szego type inequalities for these rearrangements. We also deal with the cases of equality. Our method uses, among others, some classical nonexpansivity results for rearrangements for which we provide some slight improvements. Our proof is based on the ideas of Frank and Seiringer, [J. Funct. Anal. 255 (2008), pp. 3407–3430], where a new proof to deal with the cases of equality in the nonexpansivity theorem was given, albeit in a special case involving the rearrangement of only one function.