Distill the expensive inner minimization over state-estimation errors into a neural correction term that predicts the robust barrier drift, then fine-tune the correction using differentiable closed-loop rollouts. This retains the robustness mechanism while reducing the repeated optimization cost and allowing less conservative behavior than fixed analytic uncertainty bounds.
Turn an iterative optimization or equilibrium computation inside a neural network into a differentiable layer whose backward pass solves the implicit adjoint system with conjugate gradients or GMRES using only automatic-differentiation matrix-vector products. This avoids storing unrolled iterations and avoids explicit Hessian or Jacobian construction, enabling longer solver horizons and lower-memory implicit architectures.
Train a neural trial function for an elliptic PDE using a very-weak residual in which all derivatives act on fixed smooth test functions rather than on the neural network. This eliminates second-order reverse-mode or forward-mode automatic differentiation and allows low-regularity activations while retaining a least-squares objective over many test functions.
Replace uniform collocation for a fixed random-feature neural PDE solver with sampling from the leverage-score density of the operator-applied features. Whiten the retained residual feature space before solving for output coefficients, so the sampled least-squares matrix has an identity-like expected Gram rather than inheriting severe anisotropy from the differential operator. The same construction can be used for a linearized neural network by treating Jacobian features as the trial functions.
Use the min-plus phase transition as a training-time controller: begin near p = 1/2 to preserve the initial active-state fraction across depth, then move above or below criticality to deliberately remove or create sparse pathways. The controller uses a measurable state variable, the activation zero fraction, rather than an arbitrary regularization coefficient.