Poisson Bracket Invariants and Wrapped Floer Homology
Yaniv Ganor
TL;DR
The paper develops a bridge between interlinking phenomena in symplectic geometry and the algebraic structure of wrapped Floer homology. By encoding wrapped Floer data as a persistence module with a barcode, it derives concrete lower bounds for the Poisson bracket invariant pb^+ in terms of barcode features, thereby linking dynamical interlinking to Floer-theoretic invariants. The main results yield explicit bounds pb^+ ≥ 1/(μ(b−a)) (and pb^+ ≥ 1/(μb) in a limiting case) when the wrapped Floer barcode contains a bar of the form (μ, Cμ] or (μ, ∞), with applications to cotangent bundles showing interlinking of cotangent fibers and cosphere/zero-section pairs. This framework provides a robust method to certify interlinking via persistence theory and highlights deep connections between Morse-type invariants on path spaces and symplectic invariants.
Abstract
The Poisson bracket invariants, introduced by Buhovsky, Entov, and Polterovich and further studied by Entov and Polterovich, serve as invariants for quadruples of closed sets in symplectic manifolds. Their nonvanishing has significant implications for the existence of Hamiltonian chords between pairs of sets within the quadruple, with bounds on the time-length of these chords. In this work, we establish lower bounds on the Poisson bracket invariants for certain configurations arising in the completion of Liouville domains. These bounds are expressed in terms of the barcode of wrapped Floer homology. Our primary examples come from cotangent bundles of closed Riemannian manifolds, where the quadruple consists of two fibers over distinct points and two cosphere bundles of different radii, or a single cosphere bundle and the zero section.
