2 problems

Let $\Lambda$ be an ordered abelian group, and let $G$ be a finitely generated group acting freely on a $\Lambda$-tree; such a group is called $\Lambda$-free. KMS conjecture. Every…

Lexicographic free-group conjecture. $G$ is $\mathbb{Z}^k$-free for an appropriate $k\in\mathbb{N}$, where $\mathbb{Z}^k$ is ordered lexicographically.