A Characterization of The Strong Measurability via Oscillation

  • Lee, Sang Han (Department of Mathematics Chungbuk National University) ;
  • Kim, Jin Yee (Department of Mathematics Chungbuk National University) ;
  • Kim, Mi Hye (Department of Mathematics Chungbuk National University)
  • Received : 1994.06.11
  • Published : 1994.06.30

Abstract

Let (${\Omega},{\Sigma},{\mu}$) be a measure space. A function $f:{\Omega}{\rightarrow}X$ is said to be equioscillated if for each set $A{\in}{\Sigma}$ of positive measure and for each ${\epsilon}$ > 0, there is a measurable subset B of A of positive measure such that the inequality s$sup_{{\omega}{\in}B}x^*f({\omega})-inf_{{\omega}{\in}B}x^*f({\omega})$ < ${\epsilon}$ holds for every $x^*$ with $||x^*||{\leq}1$. Strong measurability of a vector valued function is characterized using equioscillation.

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