A modification of Hardy-Littlewood maximal function on Lie groups

Autor: Maysam Maysami Sadr
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: AUT Journal of Mathematics and Computing, Vol 5, Iss 2, Pp 143-149 (2024)
Druh dokumentu: article
ISSN: 2783-2449
2783-2287
DOI: 10.22060/ajmc.2023.22259.1147
Popis: For a real-valued function $f$ on a metric measure space $(X,d,\mu)$ the Hardy-Littlewood centered-ball maximal-function of $f$ is given by the `supremum-norm':$$Mf(x):=\sup_{r>0}\frac{1}{\mu(\mathcal{B}_{x,r})}\int_{\mathcal{B}_{x,r}}|f|d\mu.$$In this note, we replace the supremum-norm on parameters $r$ by $\mathcal{L}_p$-norm with weight $w$ on parameters $r$ and define Hardy-Littlewood integral-function $I_{p,w}f$. It is shown that $I_{p,w}f$ converges pointwise to $Mf$ as $p\to\infty$. Boundedness of the sublinear operator $I_{p,w}$ and continuity of the function $I_{p,w}f$ in case that $X$ is a Lie group, $d$ is a left-invariant metric, and $\mu$ is a left Haar-measure (resp. right Haar-measure) are studied.
Databáze: Directory of Open Access Journals