The Simplicity of the Hodge Bundle

Anand Patel

Patel’s revised paper claims that for every genus g≥2, the Hodge bundle on the moduli stack of smooth complex genus-g curves has no nontrivial subbundle. The proof uses traces of involutions and curves with commuting involutions to constrain a hypothetical subbundle’s rank.

Sources for this record

What was already known

Short arguments covered the stable-curve compactification and principally polarized abelian varieties. Patel describes the corresponding smooth-curve question as open in the moduli community since about 2015.

AI involvement AI-autonomous

Patel reports that Aletheia supplied the mathematical content after one proof request with no further hints. He revised the exposition, added mathematical comments and a supporting lemma, and corrected the displayed equation.

The disclosure says Aletheia supplied the proof's mathematical content from one prompt without further mathematical hints; Patel's later exposition and correction do not erase that origin.

Importance Notable

The proof resolves the smooth-curve version of a recurring Hodge-bundle question.

Limitations

The revised paper corrects a missing factor of four in one displayed equation, and Patel says the remainder is unaffected. No complete human or machine proof check is documented; claims in other characteristics are outside this theorem.

Technical verification Partial

Patel's v3 Human Comment 2.8 identifies and repairs his omitted factor 4 in the involution-eigenspace equation and states the remaining proof is unaffected. That is documented checking of a specific proof step, but no complete human or machine check of the whole theorem is stated.

Independent checking

Correction during rewriting of the model output and inspection of the downstream proof

Checker
Anand Patel, human author
Scope
The factor 4 in the second equality of Lemma 2.7 and its use in the final rank-divisibility step
Basis
Reported by the linked checker
Evidence source

Human understanding Full

Patel explains the role of automorphisms and involution traces, proposes an alternative algebraic route for a central lemma, adds a supporting proof, and explains the final divisibility mechanism. These are person-specific explanations beyond model prose.

Correction and publication history