Symmetric Poisson geometry, totally geodesic foliations and Jacobi-Jordan algebras
Filip Moučka, Roberto Rubio
TL;DR
This work develops symmetric Poisson geometry as the natural analogue of Poisson geometry for degenerate metrics, formulating symmetric Poisson structures as pairs $(\vartheta,\nabla)$ with the key integrability $[\vartheta,\vartheta]_s=0$ and distinguishing strong from involutive cases. It builds a comprehensive toolkit—symmetric Cartan calculus, the symmetric Schouten bracket, and the Patterson–Walker construction—to interpret these structures geometrically via characteristic distributions, leaf metrics, and leaf connections, and dynamically via Patterson–Walker dynamics on $T^*M$. The authors show that involutive structures induce totally geodesic partitions with leafwise non-degenerate Poisson data, and that strong cases provide leaf Levi-Civita connections; they also establish a deep link between linear symmetric Poisson structures and Jacobi–Jordan algebras, offering a clear algebraic-geometric correspondence. Collectively, the paper lays foundational connections between symmetric bivectors, geodesic invariance, foliations, and algebraic structures, with potential implications for geometry, dynamics, and pseudo-Riemannian or sub-Riemannian contexts.
Abstract
We introduce symmetric Poisson structures as pairs consisting of a symmetric bivector field and a torsion-free connection satisfying an integrability condition analogous to that in usual Poisson geometry. Equivalent conditions in Poisson geometry have inequivalent analogues in symmetric Poisson geometry and we distinguish between symmetric and strong symmetric Poisson structures. We prove that symmetric Poisson structures correspond to locally geodesically invariant distributions together with a characteristic metric, whereas strong symmetric Poisson structures correspond to totally geodesic foliations together with a leaf metric and a leaf connection. We introduce, using the Patterson-Walker metric, a dynamics on the cotangent bundle and show its connection to symmetric Poisson geometry, the parallel transport equation and the Newtonian equation for conservative systems. Finally, we prove that linear symmetric Poisson structures are in correspondence with Jacobi-Jordan algebras, whereas strong symmetric correspond to those that are moreover associative.
