Properties of resonant states for generic smooth expanding maps

arXiv:2607.25686 2026 Dynamics 1 ideas extracted · analyzed Aug 31, 2026

What the math gives to ML

The paper develops a genericity mechanism for resonant states of smooth expanding maps: resonances are generically simple, real resonant states are Morse functions, and zero is a regular value. The most transferable construction is a finite-dimensional observability criterion: evaluations of distinct real and imaginary modes at sufficiently many points form an invertible matrix. A neural-network analogue can regularize learned recurrent or state-space dynamics so that estimated Koopman modes remain linearly independent and geometrically nondegenerate. The method is falsifiable through singular-value gaps, eigenvalue separation, critical-point Hessians, and a predicted rank transition when the number of informative observation points reaches the number of modes.

Ideas from this paper

Unverified 2026

Resonant-Mode Observability Regularizer

For a learned recurrent or state-space model, estimate leading Koopman or transfer-operator modes and force their evaluations on a small set of latent states to be linearly independent. This transfers the paper's generic invertibility construction and discourages duplicated, weakly observable, or spectrally collapsed dynamical modes, potentially improving long-horizon prediction and interpretability.

Useful6/10
Difficulty6/10
Novelty8/10
Paper: Properties of resonant states for generic smooth expanding maps arXiv:2607.25686