The groups $Γ_{n}^{4}$, braids, and $3$-manifolds

Vassily Olegovich Manturov, Igor Mikhailovich Nikonov

Published 2023-05-10Version 1

We introduce a family of groups $\Gamma_n^k$ for integer parameters $n>k$. These groups originate from discussion of braid groups on $2$-surfaces. On the other hand, they turn out to be related to 3-manifolds (in particular, they lead to new relationships between braids and manifolds), triangulations (ideal triangulations) cluster algebras, dynamics of moving points, quivers, hyperbolic structures, tropical geometry, and, probably, many other areas still to be discovered. Among crucial reason of this importance of groups $\Gamma_{n}^{4}$ we mention the Ptolemy relation, Pentagon relation, cluster algebra, Stasheff polytope.