Proved
Exact scoped statement in cited source ↗
Only the cited assertion with its exact assumptions. This report does not resolve the canonical Problem or establish independent OpenMath mathematical review.
Observed Oct 10, 2026
Theorem · version 2
For every abelian fourfold A over a finite field k = F_q and prime ℓ ≠ char(k), CH²(A)⊗Q_ℓ → H⁴_et(A_kbar,Q_ℓ(2))^{Gal(kbar/k)} is surjective. Combined with the divisor theorem and hard Lefschetz, Tate holds for A in all codimensions.
A cited preprint theorem about ℓ-adic classes over finite fields. No all-powers or all-dimensional statement is included.
Proved
Only the cited assertion with its exact assumptions. This report does not resolve the canonical Problem or establish independent OpenMath mathematical review.
Observed Oct 10, 2026
In this problem · publication v13 · Selected context
Different statement · related variant · Proved
Hodge asks for Betti Hodge classes over C; Tate asks for Galois-invariant ℓ-adic classes over finite fields. Broe’s proof uses Markman’s geometric input with further specialization arguments.
This relationship is not a direct implication from the fourfold corollary alone, or a new case of canonical Hodge.
Proved · version 2
The rational Hodge conjecture holds for every complex abelian variety of dimension four.
Scope: All codimensions on abelian fourfolds. No restriction to Weil discriminant 1 is needed for this corollary.
Proved · version 2
For every abelian fourfold A over a finite field k = F_q and prime ℓ ≠ char(k), CH²(A)⊗Q_ℓ → H⁴_et(A_kbar,Q_ℓ(2))^{Gal(kbar/k)} is surjective. Combined with the divisor theorem and hard Lefschetz, Tate holds for A in all codimensions.
Scope: A cited preprint theorem about ℓ-adic classes over finite fields. No all-powers or all-dimensional statement is included.
Relationship not independently reviewed.
Connection in Hodge conjecture →Relationship not independently reviewed. This concerns its use in this problem.
In this problem · publication v15
Different statement · related variant · Proved
Hodge asks for Betti Hodge classes over C; Tate asks for Galois-invariant ℓ-adic classes over finite fields. Broe’s proof uses Markman’s geometric input with further specialization arguments.
This relationship is not a direct implication from the fourfold corollary alone, or a new case of canonical Hodge.
Proved · version 2
The rational Hodge conjecture holds for every complex abelian variety of dimension four.
Scope: All codimensions on abelian fourfolds. No restriction to Weil discriminant 1 is needed for this corollary.
Proved · version 2
For every abelian fourfold A over a finite field k = F_q and prime ℓ ≠ char(k), CH²(A)⊗Q_ℓ → H⁴_et(A_kbar,Q_ℓ(2))^{Gal(kbar/k)} is surjective. Combined with the divisor theorem and hard Lefschetz, Tate holds for A in all codimensions.
Scope: A cited preprint theorem about ℓ-adic classes over finite fields. No all-powers or all-dimensional statement is included.
Relationship not independently reviewed.
Connection in Hodge conjecture →Relationship not independently reviewed. This concerns its use in this problem.
For an abelian fourfold over F_q and ℓ ≠ char(F_q), the ℓ-adic cycle-class map in codimension two surjects onto Galois-invariant H⁴; other codimensions follow from divisor and Lefschetz results.
paraphrase · Only metadata and original OpenMath paraphrases are published; full text stays upstream.
Matt Broe · Preprint · Publication date Aug 19, 2026
Source-reported manuscript at this exact revision; independent mathematical review is pending.
Source revision: arxiv-v1. Observed Oct 10, 2026.
The cited source does not report AI involvement; no absence claim is inferred.
Broe · Tate for abelian fourfolds over finite fields — manuscript: arxiv-v1. External manuscript. No OpenMath proof execution, formalization or independent mathematical acceptance is inferred.
The rational Hodge conjecture holds for every complex abelian variety of dimension four.
paraphrase · No upstream full text or code is republished by this record.
Eyal Markman · Preprint
Author preprint at the cited revision; journal acceptance has not been established by this curation.
Source revision: arxiv-v2. Observed Oct 10, 2026.
The cited work does not report AI involvement; this is not an assertion that no AI was used.
Source updated Jun 8, 2025.
Statement versions and problem publication versions are separate. A new publication can update context or sources while retaining the same statement.
Assessments retained in these publication records. Earlier statement versions retain their own source histories.
Proved
Only the cited assertion with its exact assumptions. This report does not resolve the canonical Problem or establish independent OpenMath mathematical review.
Observed Oct 10, 2026 · Source passage →