Partial Poisson Lie groups and groupoids. Application to Von Neumann algebras
Fernand Pelletier, Patrick Cabau
TL;DR
The paper develops a comprehensive framework for partial Poisson and sub-Poisson geometry in the convenient (often infinite-dimensional) setting, extending Weinstein’s finite-dimensional Poisson-Lie theory to Banach and broader convenient spaces. It systematically builds the theory from partial Poisson manifolds through to convenient Lie groups and groupoids, introducing linear anchors $P$ and bivector data $oldsymbol\Lambda$ that satisfy Jacobi-type conditions via Schouten brackets, and showing how these structures induce partial bialgebroids and dual pairs. A central theme is the use of direct/indirect limits to construct new examples of (partial) Poisson-Lie groups and groupoids that are not Banach-Lie in the classical sense, while maintaining a coherent infinitesimal-to-global correspondence via algebroid duals and conormal bundles. The work further connects this framework to operator algebras, illustrating how Odzijewicz-type groupoids associated to Von Neumann algebras fit into the partial Poisson-Convenient setting, and it lays groundwork for potential applications in infinite-dimensional Poisson geometry and quantum groups. Overall, the manuscript provides a self-contained, rigorous extension of finite-dimensional Poisson-Lie theory to convenient/ Banach contexts, including detailed constructions of multiplicative forms, coisotropic/lagrangian relations, and direct-limit groupoid examples with implications for Von Neumann algebra theory.
Abstract
The purpose of this paper is to propose a version of the notion of convenient Lie groupoid as a generalization of this concept in finite dimension. The authors point out which obstructions appear in the infinite dimensional context and how an adapted notion of "bi-algebroid " in finite dimension (cf. \cite{MaXu94}) can be, nevertheless, recovered. This paper is self-contained and recalls some important properties of "partial Poisson manifolds" (cf. \cite{CaPe23}, Chapter~7) and "Banach Poisson Lie groups" (cf. \cite{Tum20}) needed for their purpose. The paper also gives an illustration of these concepts from all the results of A.~Odzijewicz and his collaborators on Lie groupoids and Von Neumann algebras.
