Sharp bounds for stochastic proximal and projection estimators via radial dominance
arXiv:2607.08670
2026
Architecture
2 ideas extracted · analyzed Aug 30, 2026
What the math gives to ML
The paper provides a constructive zeroth-order approximation to proximal maps and metric projections: perturb an input with Gaussian noise, exponentially reweight samples by an energy, and return their barycenter. Its transferable asset is the covariance formula for the Jacobian and the resulting cocoercivity guarantee for weakly convex energies, which give a principled stability bound for a stochastic neural layer. This can replace an expensive implicit proximal solve with a small Monte Carlo module using only function evaluations. The strongest applications are energy-based activations and differentiable constraint layers where exact proximal computation is unavailable or costly.
Ideas from this paper
✗ Mechanism failed
2026
Replace an expensive proximal activation or implicit optimization layer with a Gaussian barycentric estimator computed from energy evaluations. The resulting map is smooth and has a provable cocoercivity guarantee when the energy is weakly convex, making it a stable alternative to unconstrained learned activations or iterative proximal solvers.
Useful7/10
Difficulty5/10
Novelty6/10
Unverified
2026
Construct a differentiable approximate projection layer for a convex feasible set by averaging Gaussian perturbations conditioned on feasibility. Unlike hard projection or penalty methods, the output is smooth in the input and inherits firm nonexpansiveness in the convex case.
Useful6/10
Difficulty4/10
Novelty5/10