Hugging Face Trending Papers
4d ago

Iterated Narrow Networks: Turing Completeness at Width 4 on Convex Input Spaces and the Complexity of Verification

The paper constructs a width‑4 ReLU network whose iterates simulate any deterministic Turing machine, with polynomial‑time construction and depth per iteration. It shows that reachability for such iterated networks is NP‑complete, NEXP‑complete, or undecidable depending on the time bound, and extends these hardness results to width‑6 networks with common smooth activations and to discretized Neural ODEs in dimension 5.

arXiv Machine Learning
Sep 4

Parameterized Hardness of Zonotope Containment and Neural Network Verification

The paper proves that several decision and approximation problems for ReLU neural networks are computationally hard. For any number of layers λ≥2, deciding whether a network’s output is positive (and thus whether it is surjective) is W[ℓ−1]-hard when parameterized by the input dimension d. In particular, for two-layer networks, the related geometric problem of zonotope non‑containment is W[1]-hard in the ambient dimension, and computing or approximating the Lp‑Lipschitz constant is NP‑hard and W[ℓ−1]-hard with respect to d. The results also show that these problems remain hard when parameterized by the number of layers for constant d, implying that naive enumeration algorithms running in n^{(ℓ−1)d}·poly(N) time are essentially optimal under the Exponential Time Hypothesis.

By Vincent Froese, Moritz Grillo, Christoph Hertrich, Moritz Stargalla