论文标题
$ m $ m $ - 紧凑型操作员的球近端
Ball proximinality of $M$-ideals of compact operators
论文作者
论文摘要
在本文中，我们证明了紧凑型操作员的封闭式单位球的近端。我们还证明了双胞胎中$ m $ $ m $的近端。此外，我们表明$ \ nathcal {k}（\ ell_1）$，$ \ ell_1 $上紧凑型操作员的空间是$ \ mathcal {b}（\ ell_1）$的球近端，$ \ ell_1 $ \ ell_1 $，甚至$ \ mathcal $ n y_1}（k k nid）（ $ \ MATHCAL {B}（\ ELL_1）$。
In this article, we prove the proximinality of closed unit ball of $M$-ideals of compact operators. We also prove the ball proximinality of $M$-embedded spaces in their biduals. Moreover, we show that $\mathcal{K}(\ell_1)$, the space of compact operators on $\ell_1$, is ball proximinal in $\mathcal{B}(\ell_1)$, the space of bounded operators on $\ell_1$, even though $\mathcal{K}(\ell_1)$ is not an $M$-ideal in $\mathcal{B}(\ell_1)$.
