Yau’s nodal bounds: surfaces and higher dimensions
OpenAI research collection · 3 manuscripts · Source checked 2026-10-19
OpenAI's result summary
Proves the sharp C\sqrt\lambda upper bound for nodal length on every fixed smooth closed surface, completing Yau's conjecture there. The upper bound fails for fixed smooth metrics in dimensions three and four, including metrics on S^(3) arbitrarily close to round. In dimension five, nodal measure can grow faster than \lambda^{1/2+\varepsilon_0} for some fixed \varepsilon_0> 0, ruling out even arbitrarily small power losses.
Read the manuscripts
Short excerpts below come from OpenAI's abstracts. The full abstract and original PDF preserve the paper's precise scope.
MANUSCRIPT 01
Sharp nodal length on smooth surfaces
We prove that a nonzero real Laplace eigenfunction with eigenvalue λ > 0 on a fixed smooth closed connected Riemannian surface has nodal length at most C\sqrt\lambda. Together with the known lower bound, this proves Yau's conjecture in this setting.
This exact PDF is not listed in the imported formalization catalogue. Family scope notes may contain further information.
Smooth counterexamples to Yau's nodal upper bound in dimensions three and four
We construct a smooth metric on the three-sphere, arbitrarily close to the round metric in the smooth topology, and a smooth metric on S^2×\mathbb T^2 for which sequences of exact real Laplace eigenfunctions have unbounded nodal measure divided by the square root of the eigenvalue. Each sequence belongs to one fixed metric.…
Full source abstract
We construct a smooth metric on the three-sphere, arbitrarily close to the round metric in the smooth topology, and a smooth metric on S^2×\mathbb T^2 for which sequences of exact real Laplace eigenfunctions have unbounded nodal measure divided by the square root of the eigenvalue. Each sequence belongs to one fixed metric. Thus the upper-bound part of Yau's nodal conjecture fails for smooth metrics in dimensions three and four.
This PDF is listed in OpenAI's formalization catalogue. See the scope and dependencies before interpreting coverage.
We construct a smooth Riemannian metric on S^4× S^1 and a sequence of real Laplace eigenfunctions whose nodal four-volume grows faster than \lambda^{1/2+\epsilon_0} for one fixed \epsilon_0> 0. This disproves the smooth upper-bound assertion in Yau's nodal-set conjecture and the proposed bound with an arbitrarily small positive…
Full source abstract
We construct a smooth Riemannian metric on S^4× S^1 and a sequence of real Laplace eigenfunctions whose nodal four-volume grows faster than \lambda^{1/2+\epsilon_0} for one fixed \epsilon_0> 0. This disproves the smooth upper-bound assertion in Yau's nodal-set conjecture and the proposed bound with an arbitrarily small positive power loss.
This PDF is listed in OpenAI's formalization catalogue. See the scope and dependencies before interpreting coverage.
New mathematical reasoning could help AI tackle harder scientific and computational problems. How reliably these skills transfer beyond mathematics will determine how much they contribute to general intelligence.