Open Access

Outer measures and weak type estimates of Hardy-Littlewood maximal operators

Journal of Inequalities and Applications20062006:15063

DOI: 10.1155/JIA/2006/15063

Received: 14 June 2004

Accepted: 14 October 2004

Published: 8 February 2006


We will introduce the times modified centered and uncentered Hardy-Littlewood maximal operators on nonhomogeneous spaces for . We will prove that the times modified centered Hardy-Littlewood maximal operator is weak type bounded with constant when if the Radon measure of the space has "continuity" in some sense. In the proof, we will use the outer measure associated with the Radon measure. We will also prove other results of Hardy-Littlewood maximal operators on homogeneous spaces and on the real line by using outer measures.


Authors’ Affiliations

Department of Mathematics, Hokkaido University


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© Terasawa 2006

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