On the barcode entropy of Lagrangian submanifolds
Matthias Meiwes
TL;DR
The article develops and analyzes relative barcode entropy for Hamiltonian diffeomorphisms relative to pairs of Lagrangian submanifolds, connecting Floer-theoretic barcode growth to dynamical entropy. It establishes lower bounds linking $\hbar(\psi;L_0,L_1)$ to the topological entropy of invariant hyperbolic sets, with a sharp 2D analogue: in dimension two the entropy bounds extend to closed curves in the complement of horseshoe orbits. It also proves stability results under Hofer and $\gamma$-distances, and introduces a strong version $\mathsf{H}^R$, for which positive values are exhibited in twisted product examples, indicating robust entropy features. Collectively, these results illuminate how symplectic topology (via Lagrangian Floer data) encodes and stabilizes dynamical complexity, with applications to volume growth and topological entropy robustness in Hamiltonian systems.
Abstract
This article deals with relative barcode entropy, a notion that was recently introduced by Cineli, Ginzburg, and Gurel. We exhibit some settings in closed symplectic manifolds for which the relative barcode entropy of a Hamiltonian diffeomorphism and a pair of Lagrangian submanifolds is positive. In analogy to a result in the absolute case by the above authors, we obtain that the topological entropy of any horseshoe K is a lower bound if the two Lagrangians contain a local unstable resp. stable manifold in K. In dimension 2, we also estimate the relative barcode entropy of a pair of closed curves that lie in special homotopy classes in the complement of certain periodic orbits in K. Furthermore, we define a variant of relative barcode entropy and exhibit first examples for which it is positive. As applications, certain robustness features of the volume growth and the topological entropy are discussed.
