The Cone Generated by Positive Semidefinite Mean Polynomials

arXiv:2608.22739 2026 Regularization 1 ideas extracted · analyzed Aug 29, 2026

What the math gives to ML

The paper supplies a constructive cone of globally nonnegative even-degree polynomials built from weighted power-mean differences, unifying SOS and circuit-polynomial certificates while strictly extending SOSONC. The transferable asset is a differentiable, compositional positivity certificate: each mean-polynomial atom is nonnegative by Jensen's inequality, and sums remain nonnegative without requiring a positive-semidefinite Gram matrix. This can parameterize globally nonnegative neural penalties, energy functions, or barrier losses with richer expressivity than SOS or SONC at comparable shallow depth. The most practical first test is to replace an SOS-based polynomial regularizer or energy head with a small learned sum of mean-polynomial atoms and compare optimization, expressivity, and constraint-violation rates.

Ideas from this paper

Unverified 2026

Mean-Polynomial Positivity Head

Parameterize a nonnegative neural penalty or energy function as a sum of weighted power-mean differences applied to polynomial features of the network representation. Each atom is globally nonnegative by the power-mean inequality, so the learned penalty cannot become negative or destabilize constrained training, while the cone can represent polynomials outside SOS-plus-nonnegative-circuit certificates.

Useful5/10
Difficulty5/10
Novelty8/10
Paper: The Cone Generated by Positive Semidefinite Mean Polynomials arXiv:2608.22739