Shadowing in the presence of singularities: oriented versus standard shadowing, entropy and the structure of recurrent sets
arXiv:2608.12165
2026
Dynamics
2 ideas extracted · analyzed Sep 1, 2026
What the math gives to ML
The paper provides a sharp distinction between oriented shadowing, which permits arbitrary increasing time reparametrizations, and standard shadowing, which requires all elapsed-time distortions to remain uniformly close to one. Its key transferable mechanism is a quantitative test for temporal as well as geometric robustness: trajectories can remain spatially close while accumulating incompatible crossing times near slow regions or singularities. The paper also gives a constructive entropy criterion: a recurrent set with local standard shadowing has positive topological entropy when two nearby almost-returning orbit segments remain separated at an intermediate time. These mechanisms can be transferred to continuous-depth networks and recurrent latent dynamics as diagnostics or regularizers for time-warp robustness and long-horizon predictability.
Ideas from this paper
✗ Mechanism failed
2026
Train a continuous-depth or latent-state neural ODE to be robust not only to spatial perturbations but also to small distortions of elapsed time. Compare nominal trajectories with perturbed pseudo-trajectories under reparametrizations whose secant slopes lie in [1-epsilon,1+epsilon], and penalize failures of a single near-identity time map to track the perturbed path. This targets the paper's distinction between oriented and standard shadowing, which becomes important when the vector field…
Useful7/10
Difficulty5/10
Novelty7/10
Unverified
2026
Use the paper's separated near-return criterion as a finite-data certificate that a recurrent or latent dynamical model contains positive-complexity behavior rather than merely noisy prediction error. Detect pairs of nearby trajectories that almost return to their starting points but separate at an intermediate time, then either flag the model for long-horizon unreliability or penalize the number and strength of such events. The monitor is suited to learned world models, RNNs, and neural ODEs…
Useful6/10
Difficulty5/10
Novelty6/10