The omnidirectional trace in H 1 ($Ω$)

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Eymard, Robert, Gallouët, Thierry, Maltese, David, Oger, Lucas
Natura: Preprint
Pubblicazione: 2026
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866913140521828352
author Eymard, Robert
Gallouët, Thierry
Maltese, David
Oger, Lucas
author_facet Eymard, Robert
Gallouët, Thierry
Maltese, David
Oger, Lucas
contents We first prove that all the functions in L 2 whose directional derivative is in L 2 have a directional trace on the boundary of any open bounded domain, without assumptions on its regularity. This enables us to define the omnidirectional trace of the elements of the Sobolev space H 1 ($Ω$) for which there exists a function on the boundary that is almost everywhere equal, with respect to the directional measure, to the directional trace, regardless of the direction. The set of all these elements of H 1 ($Ω$), denoted by H 1 tr ($Ω$), is shown to be closed, and to always contain the closure in H 1 ($Ω$) of the set C 0 ($Ω$)$\cap$ H 1 ($Ω$) (it is always equal to this set in the 1D case, and can be strictly greater in higher dimensions). The omnidirectional trace always satisfies an integration-by-parts formula, which combines the values of the trace on opposite points of the boundary. Examples show that this notion enables the resolution of variational problems involving the values at the boundary of the domain.
format Preprint
id arxiv_https___arxiv_org_abs_2605_18056
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The omnidirectional trace in H 1 ($Ω$)
Eymard, Robert
Gallouët, Thierry
Maltese, David
Oger, Lucas
Analysis of PDEs
We first prove that all the functions in L 2 whose directional derivative is in L 2 have a directional trace on the boundary of any open bounded domain, without assumptions on its regularity. This enables us to define the omnidirectional trace of the elements of the Sobolev space H 1 ($Ω$) for which there exists a function on the boundary that is almost everywhere equal, with respect to the directional measure, to the directional trace, regardless of the direction. The set of all these elements of H 1 ($Ω$), denoted by H 1 tr ($Ω$), is shown to be closed, and to always contain the closure in H 1 ($Ω$) of the set C 0 ($Ω$)$\cap$ H 1 ($Ω$) (it is always equal to this set in the 1D case, and can be strictly greater in higher dimensions). The omnidirectional trace always satisfies an integration-by-parts formula, which combines the values of the trace on opposite points of the boundary. Examples show that this notion enables the resolution of variational problems involving the values at the boundary of the domain.
title The omnidirectional trace in H 1 ($Ω$)
topic Analysis of PDEs
url https://arxiv.org/abs/2605.18056