Criteria of isolated weighted homogeneous hypersurface singularities using Logarithmic vector fields

Jihao Liu, Xiping Zhang

For a reduced isolated complex hypersurface germ of dimension at least two, or an irreducible curve germ, weighted homogeneity after coordinate change is equivalent to a logarithmic holomorphic vector field transverse in the real-Euclidean sense to every sufficiently small link in those same coordinates. An invertible ambient linear part is a third equivalent condition.

Sources for this record

What was already known

Da Silva Machado and Seade posed the equivalence and proved partial cases by dimension or parity.

AI involvement AI-autonomous

The paper says the Danus system, built on Rethlas, obtained the main equivalence, the singular first-jet and contracting-flow lemmas, and the fixed-coordinate counterexample. The authors retained its self-contained proof even after recognizing Morando's contraction theorem as an alternative route.

The source explicitly attributes the main proof and counterexample to Danus and describes the present paper as AI-generated; no human mathematical input to that proof is identified.

Importance Notable

Resolves the stated weighted-homogeneity characterization within these hypotheses.

Limitations

The coordinate change must match the transversality coordinates; the paper gives a fixed-coordinate counterexample. Liu and Zhang report a human check but do not identify its checker or procedure. Their parallel human proof is separate work.

Technical verification Partial

The authors report a completed human verification of the main result and internal-system verifier checks, but do not name the human checker or describe the check's procedure. The internal verifiers are not identified as proof assistants or exact certificate checkers. A separate human proof establishes the same theorem without checking this argument, so the evidence does not meet the named-checker requirement for Formal.

Human understanding Full

Liu and Zhang's separate human paper explains the same equivalence through a contracting flow and microlocal index route; the Danus paper itself explains its first-jet and flow mechanism. This supports understanding of the result, not independent checking of every Danus step.

Correction and publication history