English

On the Topology of Neural Network Superlevel Sets

Machine Learning 2026-03-04 v1 Optimization and Control

Abstract

We show that neural networks with activations satisfying a Riccati-type ordinary differential equation condition, an assumption arising in recent universal approximation results in the uniform topology, produce Pfaffian outputs on analytic domains with format controlled only by the architecture. Consequently, superlevel sets, as well as Lie bracket rank drop loci for neural network parameterized vector fields, admit architecture-only bounds on topological complexity, in particular on total Betti numbers, uniformly over all weights.

Keywords

Cite

@article{arxiv.2603.02973,
  title  = {On the Topology of Neural Network Superlevel Sets},
  author = {Bahman Gharesifard},
  journal= {arXiv preprint arXiv:2603.02973},
  year   = {2026}
}