On the space \(\ell ^{\infty}/c_ 0\) (Q1098053)

A 1983 paper by \textit{I. E. Leonard} and \textit{J. H. M. Whitfield} presented a study of the classical space \(\ell^{\infty}/c_ 0\) [Rocky Mountain J. Math. 13, 531-539 (1983; Zbl 0548.46020)]. They proved isomorphic properties of the space, facts about the superspaces in which they are complemented, and results about complemented subspaces. Using one of their lemmas, this paper presents a corrected proof of their result that \(\ell^{\infty}/c_ 0=\ell^{\infty}\oplus \ell^{\infty}/c_ 0\). Another of their results is extended by showing that \(\ell^{\infty}/c_ 0\) is not complemented in any dual space. This is an elegant, short paper with simple direct arguments and does not need the chastisements of the Leonard-Whitfield paper to be interesting.