Integral invariant cycles in degree-one cohomology

For a one-parameter complex projective degeneration with simple-normal-crossing central fiber and smooth nearby fiber X_t, the target is surjectivity of H¹(X,Z)→H¹(X_t,Z)^T onto the monodromy invariants.

Why it matters and what counts as progress

Why it matters: It asks for an integral invariant-cycle statement, which a rational-coefficient theorem alone does not supply.

What counts as progress: Prove integral surjectivity onto the monodromy invariants; a rational-coefficient invariant-cycle theorem alone does not establish it.

How the problem developed

  1. 27 Apr 2026 · Reported solution [3][1]

    QED research team The initial QED report describes an independently generated proof of the integral degree-one invariant-cycle theorem for the stated one-parameter degeneration setting.

  2. 26 Jun 2026 · Human checked proof [1][2]

    QED research team; Yilong Zhang The revised report says Zhang verified and explained QED’s proof. It also notes that a different human proof had already been found independently; the two arguments are distinct.

AI contribution

QED: An Open-Source Multi-Agent System for Generating Mathematical Proofs on Open Problems

Chenyang An, Qihao Ye, Minghao Pan, Jiayaun Zhang

For a one-parameter complex projective degeneration with simple-normal-crossing central fiber and smooth nearby fiber X_t, QED proves that H¹(X,Z) maps onto the monodromy-invariant subgroup H¹(X_t,Z)^T.

AI involvementAI-autonomous
ImportanceNotable
Technical verificationFormal (human)
Human understandingFull
Paper date:

Sources

  1. QED research report
  2. QED project proof account
  3. QED research report (first version)
Website timeline

Publication dates and editorial changes.