On certain automorphisms of nilpotent groups. (Q2861060)

Let \(G\) be a group and \(\vartheta\in\Aut(G)\); the automorphism \(\vartheta\) is pointwise inner if \(\vartheta(g)\) is conjugate to \(g\) for every \(g\in G\) (that is \(\vartheta\) fixes the conjugacy classes of \(G\)). The set \(\Aut_{\mathrm{pwi}}(G)\) of pointwise inner automorphisms of \(G\) is a subgroup of \(\Aut(G)\) and obviously \(\mathrm{Inn}(G)\leq\Aut_{\mathrm{pwi}}(G)\).NEWLINENEWLINE The paper under review is devoted to the study of \(\Aut_{\mathrm{pwi}}(G)\) when \(G\) is a nilpotent group.