Infinite-Horizon Inverse Linear-Quadratic Differential Games with State- and Control-Dependent Noise
arXiv:2608.17939
2026
Theory
1 ideas extracted · analyzed Sep 1, 2026
What the math gives to ML
The paper provides a constructive inverse mechanism for stochastic linear-quadratic Nash equilibria: once equilibrium feedback gains are observed, the compatible state and control cost parameters lie in an explicitly computable kernel intersected with admissibility constraints. The transferable asset is an identifiability certificate: equilibrium behavior generally determines a family of objectives rather than a unique objective, and the dimension of that family can be measured by a nullspace calculation. In neural networks, this can be adapted to infer or constrain local quadratic loss metrics and optimizer preconditioners from observed parameter-update trajectories, while explicitly exposing which curvature directions are unidentifiable.
Ideas from this paper
Unverified
2026
Use a window of observed neural-network update trajectories to identify the set of local quadratic objectives and preconditioners that are consistent with the observed optimizer behavior. Rather than selecting one arbitrary curvature model, retain the nullspace of compatible parameters and use its dimension or smallest singular value as an identifiability and stability diagnostic.
Useful6/10
Difficulty6/10
Novelty8/10