The Borel complexity of the space of left-orderings, low-dimensional topology, and dynamics

التفاصيل البيبلوغرافية
العنوان: The Borel complexity of the space of left-orderings, low-dimensional topology, and dynamics
المؤلفون: Calderoni, Filippo, Clay, Adam
سنة النشر: 2023
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Logic, Mathematics - Group Theory, Mathematics - Geometric Topology
الوصف: We develop new tools to analyze the complexity of the conjugacy equivalence relation $E_\mathsf{lo}(G)$, whenever $G$ is a left-orderable group. Our methods are used to demonstrate non-smoothness of $E_\mathsf{lo}(G)$ for certain groups $G$ of dynamical origin, such as certain amalgams constructed from Thompson's group $F$. We also initiate a systematic analysis of $E_\mathsf{lo}(\pi_1(M))$, where $M$ is a $3$-manifold. We prove that if $M$ is not prime, then $E_\mathsf{lo}(\pi_1(M))$ is a universal countable Borel equivalence relation, and show that in certain cases the complexity of $E_\mathsf{lo}(\pi_1(M))$ is bounded below by the complexity of the conjugacy equivalence relation arising from the fundamental group of each of the JSJ pieces of $M$. We also prove that if $M$ is the complement of a nontrivial knot in $S^3$ then $E_\mathsf{lo}(\pi_1(M))$ is not smooth, and show how determining smoothness of $E_\mathsf{lo}(\pi_1(M))$ for all knot manifolds $M$ is related to the L-space conjecture.
Comment: A few typos have been fixed. The abstract has been modified to better reflect the content of the paper. Submitted. 23 pages
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2305.03927
رقم الأكسشن: edsarx.2305.03927
قاعدة البيانات: arXiv