Chong–Wise conjecture on embedding free-by-cyclic groups
Show that every finitely generated free-by-cyclic group embeds into a free-by-cyclic group with finitely generated free kernel.
References
\begin{conjecture}[Chong--Wise] If $G$ is a finitely generated free-by-cyclic group, then $G$ is a subgroup of a {finitely generated free}-by-cyclic group. \end{conjecture}
— The theory of one-relator groups: history and recent progress
(2501.18306 - Linton et al., 30 Jan 2025) in Subsection 5.6 (Free-by-cyclic one-relator groups)