Poisson structure on predual of Banach Lie algebroid
Tomasz Goliński, Grzegorz Jakimowicz
TL;DR
The paper addresses how to define a linear Poisson structure on the predual bundle $E_*$ of a Banach Lie algebroid and how this relates to Banach Poisson geometry. It develops a canonical, linear, localizable Poisson bracket on $E_*$ using two natural families of functions $f\circ\\pi_*$ and $\\lambda_X$, derives the Poisson tensor $\\Pi$, and provides explicit coordinate formulas that yield a Banach Poisson structure under suitable compatibility conditions. It also shows the reverse direction: from a linear Poisson bracket on $E_*$ one recovers a Banach Lie algebroid on $E$ via $[X_1,X_2] = \\lambda^{-1}(\\{\\lambda_{X_1},\\lambda_{X_2}\\})$ and $a(X) = T\\pi_* \\sharp(d\\lambda_X)$, establishing a Banach analogue of the Lie–Poisson correspondence. The paper includes illustrative examples, notably a weak symplectic structure on the precotangent bundle and a concrete trivial-bundle construction on $\\ell^2 \times \\ell^\infty$, clarifying the theory and highlighting conditions under which the predual carries a Banach Poisson structure. Together, these results extend the finite-dimensional Poisson–Lie algebroid correspondence to the Banach setting and offer practical criteria and models for infinite-dimensional Poisson geometry and potential applications in integrable systems.
Abstract
We construct the linear Poisson structure on the predual bundle of a Banach Lie algebroid. It is an alternative approach to the already known results on the linear sub-Poisson structure on the dual bundle. We also discuss the existence of queer Banach Lie algebroids. An example of a precotangent bundle is presented.
