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  • Research Article
  • Open Access

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

Journal of Inequalities and Applications20062006:15063

  • Received: 14 June 2004
  • Accepted: 14 October 2004
  • Published:


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.


  • Real Line
  • Homogeneous Space
  • Maximal Operator
  • Radon Measure
  • Weak Type


Authors’ Affiliations

Department of Mathematics, Hokkaido University, Sapporo 060-0810, Japan


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© Terasawa 2006

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