Algebraic geometry MSC2020 14C30

conjecture

Hodge conjecture

OpenGeneral case unresolved

The general statement is reported open by Clay; proved special cases have not been curated here.

Source report · observed Oct 1, 2026

Source-linked discoveryspecialist backgroundChecked Oct 1, 2026Publication v2

Viewing pinned publication v2. View the current publication →

Question & scope

On a smooth complex projective variety, is every rational Hodge class a rational linear combination of classes of algebraic cycles?

The rational Hodge conjecture; integral variants are different statements.

Question paraphrased by OpenMath. Use the cited source and locator for authoritative wording.

Research state

OpenGeneral case unresolved

The general statement is reported open by Clay; proved special cases have not been curated here.

Still unresolved: The general statement remains unresolved according to the cited source. Partial-result coverage is not assessed here.

Source report · observed Oct 1, 2026 · Clay · Millennium Problems

This is a discovery entry. OpenMath has checked the linked source and attribution; it has not independently assessed the present mathematical status.

Source label: Unsolved

Source status date unavailable · Observed Oct 1, 2026

The cited source item and version only; this is not an independent OpenMath assessment.

Literature & sources

Provenance & coverage

Published after staff preview and source checks. This page covers the cited items; it does not represent a complete list of problems or a literature-wide review.

  • No exhaustive literature or source-list coverage.
  • Independent mathematical assessment has not been performed.

Clay · Millennium Problems ↗

Clay Mathematics Institute · metadata-link · Not established; links and OpenMath paraphrases only

Store metadata and original OpenMath paraphrases; follow the original source for authoritative wording. Rights / source terms

1 cited entry · exact source identity
Version
clay-millennium@observed-2026-10-01
Revision
observed-2026-10-01
Content SHA-256
No upstream byte snapshot retained; linked metadata only
Source update
Unavailable
Observed
2026-10-01
Check cadence
30 days
Publication v2 · history & checksums
Stable Problem ID
problem-hodge-conjecture
Publication SHA-256
1be285c6bd00ce06475f059615a54bc1e95f7b6f21ae2e13031cd74c95f6687f
Published
2026-10-10T06:01:24.736315+00:00
Publication reason
Add cited resolution scope and consolidate equivalent prime formulations and supporting Claims; mathematical evidence and execution review remain distinct.
  1. v1 · publish · Sep 30, 2026

    Initial checked pilot publication; source attribution, rights, wording and coverage reviewed by OpenMath staff.

  2. v2 · publish · Oct 10, 2026

    Add cited resolution scope and consolidate equivalent prime formulations and supporting Claims; mathematical evidence and execution review remain distinct.

  3. v3 · publish · Oct 10, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  4. v4 · publish · Oct 10, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  5. v5 · publish · Oct 10, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  6. v6 · publish · Oct 11, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  7. v7 · publish · Oct 11, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  8. v8 · publish · Oct 11, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  9. v9 · publish · Oct 11, 2026

    Publish checked pilot curation with canonical Claims and scoped progress; preserve exact source revisions, assumptions, coverage limits and historical publications. External artifacts and OpenMath execution remain distinct.

  10. v10 · publish · Oct 11, 2026

    Reviewed reader correction: preserve assertion history, exact citations and scoped assessments; task evidence names its exact Claim target.

  11. v11 · publish · Oct 12, 2026

    Reviewed reader correction: preserve assertion history, exact citations and scoped assessments; task evidence names its exact Claim target.

  12. v12 · publish · Oct 13, 2026

    Reviewed reader correction: preserve assertion history, exact citations and scoped assessments; task evidence names its exact Claim target.

  13. v13 · publish · Oct 13, 2026

    Reviewed reader correction: preserve assertion history, exact citations and scoped assessments; task evidence names its exact Claim target.

  14. v14 · publish · Oct 15, 2026

    Reviewed reader correction: preserve assertion history, exact citations and scoped assessments; task evidence names its exact Claim target.

  15. v15 · publish · Oct 15, 2026

    Reviewed reader correction: preserve assertion history, exact citations and scoped assessments; task evidence names its exact Claim target.