Sadek Gala and Yoshihiro Sawano University of mostaganem, Kyoto University
Abstract : In this paper, we will provide an alternative proof to characterize the pointwise multipliers which maps a Sobolev space $\overset{.}{H}^{r}\left( \mathbb{R}^{d}\right) $ to its dual $\overset{.}{H}^{-r}\left( \mathbb{R} ^{d}\right) $ in the case $0