On the constants for some Sobolev imbeddings
<p/> <p>We consider the imbedding inequality <inline-formula><graphic file="1029-242X-2001-823805-i1.gif"/></inline-formula> is the Sobolev space (or Bessel potential space) of <inline-formula><graphic file="1029-242X-2001-823805-i2.gif"/>...
Main Authors: | , |
---|---|
Format: | Article |
Language: | English |
Published: |
SpringerOpen
2001-01-01
|
Series: | Journal of Inequalities and Applications |
Subjects: | |
Online Access: | http://www.journalofinequalitiesandapplications.com/content/6/823805 |
_version_ | 1819059924952416256 |
---|---|
author | Pizzocchero Livio Morosi Carlo |
author_facet | Pizzocchero Livio Morosi Carlo |
author_sort | Pizzocchero Livio |
collection | DOAJ |
description | <p/> <p>We consider the imbedding inequality <inline-formula><graphic file="1029-242X-2001-823805-i1.gif"/></inline-formula> is the Sobolev space (or Bessel potential space) of <inline-formula><graphic file="1029-242X-2001-823805-i2.gif"/></inline-formula> type and (integer or fractional) order <inline-formula><graphic file="1029-242X-2001-823805-i3.gif"/></inline-formula>. We write down upper bounds for the constants <inline-formula><graphic file="1029-242X-2001-823805-i4.gif"/></inline-formula>, using an argument previously applied in the literature in particular cases. We prove that the upper bounds computed in this way are in fact the sharp constants if <inline-formula><graphic file="1029-242X-2001-823805-i5.gif"/></inline-formula>, <inline-formula><graphic file="1029-242X-2001-823805-i6.gif"/></inline-formula>, and exhibit the maximising functions. Furthermore, using convenient trial functions, we derive lower bounds on <inline-formula><graphic file="1029-242X-2001-823805-i7.gif"/></inline-formula> for <inline-formula><graphic file="1029-242X-2001-823805-i8.gif"/></inline-formula> in many cases these are close to the previous upper bounds, as illustrated by a number of examples, thus characterizing the sharp constants with little uncertainty.</p> |
first_indexed | 2024-12-21T14:18:50Z |
format | Article |
id | doaj.art-302fec60347946ea9bab655a77141f2e |
institution | Directory Open Access Journal |
issn | 1025-5834 1029-242X |
language | English |
last_indexed | 2024-12-21T14:18:50Z |
publishDate | 2001-01-01 |
publisher | SpringerOpen |
record_format | Article |
series | Journal of Inequalities and Applications |
spelling | doaj.art-302fec60347946ea9bab655a77141f2e2022-12-21T19:00:50ZengSpringerOpenJournal of Inequalities and Applications1025-58341029-242X2001-01-0120016823805On the constants for some Sobolev imbeddingsPizzocchero LivioMorosi Carlo<p/> <p>We consider the imbedding inequality <inline-formula><graphic file="1029-242X-2001-823805-i1.gif"/></inline-formula> is the Sobolev space (or Bessel potential space) of <inline-formula><graphic file="1029-242X-2001-823805-i2.gif"/></inline-formula> type and (integer or fractional) order <inline-formula><graphic file="1029-242X-2001-823805-i3.gif"/></inline-formula>. We write down upper bounds for the constants <inline-formula><graphic file="1029-242X-2001-823805-i4.gif"/></inline-formula>, using an argument previously applied in the literature in particular cases. We prove that the upper bounds computed in this way are in fact the sharp constants if <inline-formula><graphic file="1029-242X-2001-823805-i5.gif"/></inline-formula>, <inline-formula><graphic file="1029-242X-2001-823805-i6.gif"/></inline-formula>, and exhibit the maximising functions. Furthermore, using convenient trial functions, we derive lower bounds on <inline-formula><graphic file="1029-242X-2001-823805-i7.gif"/></inline-formula> for <inline-formula><graphic file="1029-242X-2001-823805-i8.gif"/></inline-formula> in many cases these are close to the previous upper bounds, as illustrated by a number of examples, thus characterizing the sharp constants with little uncertainty.</p>http://www.journalofinequalitiesandapplications.com/content/6/823805Sobolev spacesImbedding inequalities |
spellingShingle | Pizzocchero Livio Morosi Carlo On the constants for some Sobolev imbeddings Journal of Inequalities and Applications Sobolev spaces Imbedding inequalities |
title | On the constants for some Sobolev imbeddings |
title_full | On the constants for some Sobolev imbeddings |
title_fullStr | On the constants for some Sobolev imbeddings |
title_full_unstemmed | On the constants for some Sobolev imbeddings |
title_short | On the constants for some Sobolev imbeddings |
title_sort | on the constants for some sobolev imbeddings |
topic | Sobolev spaces Imbedding inequalities |
url | http://www.journalofinequalitiesandapplications.com/content/6/823805 |
work_keys_str_mv | AT pizzoccherolivio ontheconstantsforsomesobolevimbeddings AT morosicarlo ontheconstantsforsomesobolevimbeddings |