2019/02/08 by Misha Gekhtman, Gekhtman, Misha, Michael Shapiro +3
Mathematics · #13F60 #53D17 #Advanced Algebra and Geometry #Algebraic structures and combinatorial models #FOS: Mathematics #Homotopy and Cohomology in Algebraic Topology #Quantum Algebra (math.QA)
paper · pdf · doi:10.48550/arxiv.1902.02902
openalex publication_date 2019/02/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We continue the study of multiple cluster structures in the rings of regular functions on GLn, SLn and Matn that are compatible with Poisson-Lie and Poisson-homogeneous structures. According to our initial conjecture, each class in the Belavin-Drinfeld classification of Poisson--Lie structures on a semisimple complex group \mathcal G corresponds to a cluster structure in \mathcal O(\mathcal G). Here we prove this conjecture for a large subset of Belavin-Drinfeld (BD) data of An type, which includes all the previously known examples. Namely, we subdivide all possible An type BD data into oriented and non-oriented kinds. In the oriented case, we single out BD data satisfying a certain combinatorial condition that we call aperiodicity and prove that for any BD data of this kind there exists a regular cluster structure compatible with the corresponding Poisson-Lie bracket. In fact, we extend the aperiodicity condition to pairs of oriented BD data and prove a more general result that establishes an existence of a regular cluster structure on SLn compatible with a Poisson bracket homogeneous with respect to the right and left action of two copies of SLn equipped with two different Poisson-Lie brackets. If the aperiodicity condition is not satisfied, a compatible cluster structure has to be replaced with a generalized cluster structure. We will address this situation in future publications.