发表机构
Magdalen College, University of Oxford(牛津大学马格达伦学院)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
本文证明 $\mathbb{Z}$ 的 lampshuffler 群中的子群及子幺半群成员问题可判定,通过将其归约至已知可判定的圈积 $H \wr \mathbb{Z}$ 的子群成员问题。
AI 中文摘要
$\mathbb{Z}$ 的 lampshuffler 群是半直积 $\operatorname{FSym}(\mathbb{Z}) \rtimes \mathbb{Z}$,它由所有在有限集外表现为平移的 $\mathbb{Z}$ 上的置换组成。这个无限置换群自然地包含每个有限群 $H$ 的圈积 $H \wr \mathbb{Z}$ 作为其子群。我们证明子群成员问题,更一般地,子幺半群成员问题在 $\operatorname{FSym}(\mathbb{Z}) \rtimes \mathbb{Z}$ 中是可判定的。我们的证明将 $\operatorname{FSym}(\mathbb{Z}) \rtimes \mathbb{Z}$ 中的子群与子幺半群成员问题归约到圈积 $H \wr \mathbb{Z}$ 中的子群成员问题,后者已被 Lohrey、Steinberg 和 Zetzsche(2015)证明为可判定。
英文摘要
The lampshuffler group of $\mathbb{Z}$ is the semidirect product $\operatorname{FSym}(\mathbb{Z}) \rtimes \mathbb{Z}$, which consists of all permutations of $\mathbb{Z}$ that act as a translation outside a finite set. This infinite permutation group naturally contains as subgroups the wreath products $H \wr \mathbb{Z}$ for every finite group $H$. We prove that the Subgroup Membership Problem, and more generally, the Submonoid Membership Problem, are decidable in $\operatorname{FSym}(\mathbb{Z}) \rtimes \mathbb{Z}$. Our proof reduces Subgroup and Submonoid Membership in $\operatorname{FSym}(\mathbb{Z}) \rtimes \mathbb{Z}$ to Subgroup Membership in the wreath products $H \wr \mathbb{Z}$, which was shown to be decidable by Lohrey, Steinberg and Zetzsche (2015).
Commentsappears in SODA'27