{
  "registry": "Mathematics Codex — Proof Status Board",
  "url": "/mathematics/proof-status/",
  "version": "1.3",
  "generated": "2026-05-27",
  "codex_version": "2.5",
  "status_values": [
    "open",
    "proven",
    "disproven",
    "independent"
  ],
  "verification_tiers": {
    "peer-reviewed": "Traditional human peer review of a written proof",
    "computer-assisted": "Machine computation essential to the proof; programs human-checked",
    "formally-verified": "Every logical step machine-checked in a proof assistant (Lean/Coq/Isabelle/HOL Light)"
  },
  "results": [
    {
      "id": "fermats-last-theorem",
      "title": "Fermat's Last Theorem",
      "statement_short": "No positive integers a,b,c satisfy a^n+b^n=c^n for integer n>2.",
      "status": "proven",
      "year_posed": "1637",
      "posed_by": "Pierre de Fermat",
      "year_resolved": "1995",
      "resolved_by": "Andrew Wiles (with Richard Taylor)",
      "verification": "peer-reviewed",
      "formalization_notes": "Full formalization in Lean in progress (project led by Kevin Buzzard, begun 2024)",
      "prize": null,
      "codex_entry": "/mathematics/named-results/fermats-last-theorem/",
      "sources": [
        "Wiles, A. (1995). Modular elliptic curves and Fermat's Last Theorem. Annals of Mathematics, 141(3), 443-551."
      ]
    },
    {
      "id": "poincare-conjecture",
      "title": "Poincaré Conjecture",
      "statement_short": "Every simply connected closed 3-manifold is homeomorphic to the 3-sphere.",
      "status": "proven",
      "year_posed": "1904",
      "posed_by": "Henri Poincaré",
      "year_resolved": "2003",
      "resolved_by": "Grigori Perelman (verification by independent teams completed 2006)",
      "verification": "peer-reviewed",
      "formalization_notes": null,
      "prize": "Clay Millennium Prize — solved (awarded 2010; declined by Perelman)",
      "codex_entry": "/mathematics/topology/poincare-conjecture/",
      "sources": [
        "Perelman, G. (2002-2003). arXiv preprints: math/0211159, math/0303109, math/0307245."
      ]
    },
    {
      "id": "four-colour-theorem",
      "title": "Four Colour Theorem",
      "statement_short": "Every planar map can be coloured with at most four colours so no adjacent regions share a colour.",
      "status": "proven",
      "year_posed": "1852",
      "posed_by": "Francis Guthrie",
      "year_resolved": "1976",
      "resolved_by": "Kenneth Appel and Wolfgang Haken",
      "verification": "formally-verified",
      "formalization_notes": "Originally computer-assisted (1976); fully formally verified by Georges Gonthier in Coq (2005)",
      "prize": null,
      "codex_entry": "/mathematics/discrete/four-colour-theorem/",
      "sources": [
        "Appel, K. and Haken, W. (1977). Every planar map is four colorable. Illinois Journal of Mathematics, 21(3).",
        "Gonthier, G. (2008). Formal proof — the Four-Color Theorem. Notices of the AMS, 55(11), 1382-1393."
      ]
    },
    {
      "id": "kepler-conjecture",
      "title": "Kepler Conjecture",
      "statement_short": "No sphere packing in 3D exceeds density pi/sqrt(18) ~= 74.05% (cannonball stacking is optimal).",
      "status": "proven",
      "year_posed": "1611",
      "posed_by": "Johannes Kepler",
      "year_resolved": "1998",
      "resolved_by": "Thomas Hales",
      "verification": "formally-verified",
      "formalization_notes": "Originally computer-assisted (1998, published 2005); fully formally verified by the Flyspeck project in HOL Light and Isabelle (2014)",
      "prize": null,
      "codex_entry": "/mathematics/named-results/kepler-conjecture/",
      "sources": [
        "Hales, T.C. (2005). A proof of the Kepler conjecture. Annals of Mathematics, 162(3), 1065-1185.",
        "Hales, T. et al. (2017). A formal proof of the Kepler conjecture. Forum of Mathematics, Pi, 5, e2."
      ]
    },
    {
      "id": "godels-incompleteness-theorems",
      "title": "Gödel's Incompleteness Theorems",
      "statement_short": "Any consistent formal system containing arithmetic has true statements it cannot prove; no such system can prove its own consistency.",
      "status": "proven",
      "year_posed": null,
      "posed_by": null,
      "year_resolved": "1931",
      "resolved_by": "Kurt Gödel",
      "verification": "formally-verified",
      "formalization_notes": "Formally verified in multiple systems (e.g. Paulson in Isabelle, 2013; O'Connor in Coq, 2005)",
      "prize": null,
      "codex_entry": "/mathematics/named-results/godels-incompleteness-theorems/",
      "sources": [
        "Gödel, K. (1931). Über formal unentscheidbare Sätze der Principia Mathematica und verwandter Systeme I. Monatshefte für Mathematik und Physik, 38, 173-198."
      ]
    },
    {
      "id": "basel-problem",
      "title": "Basel Problem",
      "statement_short": "Sum of reciprocal squares 1 + 1/4 + 1/9 + ... equals pi^2/6.",
      "status": "proven",
      "year_posed": "1650",
      "posed_by": "Pietro Mengoli",
      "year_resolved": "1734",
      "resolved_by": "Leonhard Euler (rigorous proof 1741)",
      "verification": "peer-reviewed",
      "formalization_notes": null,
      "prize": null,
      "codex_entry": "/mathematics/named-results/basel-problem/",
      "sources": [
        "Euler, L. (1741). De summis serierum reciprocarum. Commentarii academiae scientiarum Petropolitanae, 7, 123-134."
      ]
    },
    {
      "id": "abel-ruffini-theorem",
      "title": "Abel–Ruffini Theorem",
      "statement_short": "No general algebraic formula (in radicals) exists for polynomial equations of degree 5 or higher.",
      "status": "proven",
      "year_posed": null,
      "posed_by": null,
      "year_resolved": "1824",
      "resolved_by": "Niels Henrik Abel (Ruffini's 1799 proof was incomplete)",
      "verification": "peer-reviewed",
      "formalization_notes": null,
      "prize": null,
      "codex_entry": "/mathematics/algebra/symmetric-group/",
      "sources": [
        "Abel, N.H. (1824). Mémoire sur les équations algébriques."
      ]
    },
    {
      "id": "nash-equilibrium-existence",
      "title": "Nash Equilibrium Existence Theorem",
      "statement_short": "Every finite game has at least one equilibrium in mixed strategies.",
      "status": "proven",
      "year_posed": null,
      "posed_by": null,
      "year_resolved": "1950",
      "resolved_by": "John Nash",
      "verification": "peer-reviewed",
      "formalization_notes": null,
      "prize": null,
      "codex_entry": "/mathematics/applied/nash-equilibrium/",
      "sources": [
        "Nash, J.F. (1950). Equilibrium points in n-person games. PNAS, 36(1), 48-49."
      ]
    },
    {
      "id": "prime-number-theorem",
      "title": "Prime Number Theorem",
      "statement_short": "The number of primes below x is asymptotically x/ln(x).",
      "status": "proven",
      "year_posed": "1792-1798",
      "posed_by": "Conjectured by Gauss and Legendre",
      "year_resolved": "1896",
      "resolved_by": "Jacques Hadamard and Charles de la Vallée Poussin (independently)",
      "verification": "formally-verified",
      "formalization_notes": "Formally verified: elementary proof in Isabelle (Avigad et al., 2004); analytic proof in HOL Light (Harrison, 2009)",
      "prize": null,
      "codex_entry": "/mathematics/number-theory/prime-number/",
      "sources": [
        "Hadamard, J. (1896). Sur la distribution des zéros de la fonction zeta(s). Bulletin de la SMF, 24, 199-220."
      ]
    },
    {
      "id": "riemann-hypothesis",
      "title": "Riemann Hypothesis",
      "statement_short": "All non-trivial zeros of the zeta function have real part 1/2.",
      "status": "open",
      "year_posed": "1859",
      "posed_by": "Bernhard Riemann",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": "First 10 trillion+ zeros verified computationally to lie on the critical line — strong evidence, not proof",
      "prize": "Clay Millennium Prize ($1M) — open. Also Hilbert Problem 8.",
      "codex_entry": "/mathematics/named-results/riemann-hypothesis/",
      "sources": [
        "Riemann, B. (1859). Über die Anzahl der Primzahlen unter einer gegebenen Grösse. Monatsberichte der Berliner Akademie."
      ]
    },
    {
      "id": "collatz-conjecture",
      "title": "Collatz Conjecture",
      "statement_short": "Iterating n -> n/2 (even) or 3n+1 (odd) always reaches 1.",
      "status": "open",
      "year_posed": "1937",
      "posed_by": "Lothar Collatz",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": "Verified computationally for all starting values up to ~2^68; Tao (2019) proved 'almost all' orbits reach almost-bounded values",
      "prize": null,
      "codex_entry": "/mathematics/named-results/collatz-conjecture/",
      "sources": [
        "Tao, T. (2019). Almost all orbits of the Collatz map attain almost bounded values. arXiv:1909.03562."
      ]
    },
    {
      "id": "goldbach-conjecture",
      "title": "Goldbach Conjecture (strong form)",
      "statement_short": "Every even integer greater than 2 is the sum of two primes.",
      "status": "open",
      "year_posed": "1742",
      "posed_by": "Christian Goldbach (letter to Euler)",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": "Weak (ternary) form — every odd number >5 is a sum of three primes — proven by Harald Helfgott (2013, widely accepted). Strong form verified computationally to 4x10^18.",
      "prize": null,
      "codex_entry": "/mathematics/number-theory/goldbach-conjecture/",
      "sources": [
        "Helfgott, H.A. (2013). The ternary Goldbach conjecture is true. arXiv:1312.7748."
      ]
    },
    {
      "id": "twin-prime-conjecture",
      "title": "Twin Prime Conjecture",
      "statement_short": "There are infinitely many primes p such that p+2 is also prime.",
      "status": "open",
      "year_posed": "1849 (de Polignac, general form)",
      "posed_by": "Alphonse de Polignac",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": "Major progress: Yitang Zhang (2013) proved bounded gaps (70 million); Polymath8b reduced the bound to 246",
      "prize": null,
      "codex_entry": "/mathematics/number-theory/twin-prime-conjecture/",
      "sources": [
        "Zhang, Y. (2014). Bounded gaps between primes. Annals of Mathematics, 179(3), 1121-1174."
      ]
    },
    {
      "id": "p-vs-np",
      "title": "P vs NP",
      "statement_short": "Can every problem whose solution is quickly verifiable also be quickly solved?",
      "status": "open",
      "year_posed": "1971",
      "posed_by": "Stephen Cook (independently Leonid Levin)",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": null,
      "prize": "Clay Millennium Prize ($1M) — open",
      "codex_entry": "/mathematics/named-results/p-vs-np/",
      "sources": [
        "Cook, S.A. (1971). The complexity of theorem-proving procedures. Proceedings of the 3rd Annual ACM Symposium on Theory of Computing, 151-158."
      ]
    },
    {
      "id": "navier-stokes",
      "title": "Navier–Stokes Existence and Smoothness",
      "statement_short": "Do smooth solutions to the 3D Navier-Stokes fluid equations always exist for all time?",
      "status": "open",
      "year_posed": "19th century (equations); 2000 (formal problem statement)",
      "posed_by": "Clay Mathematics Institute (formal statement by Fefferman)",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": null,
      "prize": "Clay Millennium Prize ($1M) — open",
      "codex_entry": "/mathematics/mathematical-physics/navier-stokes-existence-and-smoothness/",
      "sources": [
        "Fefferman, C.L. (2000). Existence and smoothness of the Navier-Stokes equation. Clay Mathematics Institute."
      ]
    },
    {
      "id": "hodge-conjecture",
      "title": "Hodge Conjecture",
      "statement_short": "Certain topological classes on projective algebraic varieties are combinations of algebraic cycle classes.",
      "status": "open",
      "year_posed": "1950",
      "posed_by": "W.V.D. Hodge",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": null,
      "prize": "Clay Millennium Prize ($1M) — open",
      "codex_entry": "/mathematics/named-results/clay-millennium-problems/",
      "sources": [
        "Hodge, W.V.D. (1950). The topological invariants of algebraic varieties. Proceedings of the ICM, Cambridge, MA."
      ]
    },
    {
      "id": "birch-swinnerton-dyer",
      "title": "Birch and Swinnerton-Dyer Conjecture",
      "statement_short": "The rank of an elliptic curve's rational points is determined by the behaviour of its L-function at s=1.",
      "status": "open",
      "year_posed": "1965",
      "posed_by": "Bryan Birch and Peter Swinnerton-Dyer",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": null,
      "prize": "Clay Millennium Prize ($1M) — open",
      "codex_entry": "/mathematics/named-results/clay-millennium-problems/",
      "sources": [
        "Birch, B.J. and Swinnerton-Dyer, H.P.F. (1965). Notes on elliptic curves. II. Journal für die reine und angewandte Mathematik, 218, 79-108."
      ]
    },
    {
      "id": "yang-mills-mass-gap",
      "title": "Yang–Mills Existence and Mass Gap",
      "statement_short": "Prove quantum Yang-Mills theory exists rigorously on R^4 and has a positive mass gap.",
      "status": "open",
      "year_posed": "2000 (formal problem statement)",
      "posed_by": "Clay Mathematics Institute (formal statement by Jaffe and Witten)",
      "year_resolved": null,
      "resolved_by": null,
      "verification": null,
      "formalization_notes": null,
      "prize": "Clay Millennium Prize ($1M) — open",
      "codex_entry": "/mathematics/named-results/clay-millennium-problems/",
      "sources": [
        "Jaffe, A. and Witten, E. (2000). Quantum Yang-Mills theory. Clay Mathematics Institute."
      ]
    },
    {
      "id": "continuum-hypothesis",
      "title": "Continuum Hypothesis",
      "statement_short": "There is no set whose cardinality lies strictly between the integers and the real numbers.",
      "status": "independent",
      "year_posed": "1878",
      "posed_by": "Georg Cantor",
      "year_resolved": "1963",
      "resolved_by": "Kurt Gödel (1940, consistency) + Paul Cohen (1963, independence; Fields Medal 1966)",
      "verification": "peer-reviewed",
      "formalization_notes": "Neither provable nor disprovable from the standard ZFC axioms — a fundamentally different kind of resolution. Hilbert Problem 1.",
      "prize": null,
      "codex_entry": "/mathematics/foundations-logic/continuum-hypothesis/",
      "sources": [
        "Cohen, P.J. (1963). The independence of the continuum hypothesis. PNAS, 50(6), 1143-1148.",
        "Gödel, K. (1940). The Consistency of the Continuum Hypothesis. Princeton University Press."
      ]
    },
    {
      "id": "mertens-conjecture",
      "title": "Mertens Conjecture",
      "statement_short": "The Mertens function M(n) is bounded by sqrt(n) in absolute value for all n>1.",
      "status": "disproven",
      "year_posed": "1897",
      "posed_by": "Franz Mertens (earlier Stieltjes, 1885)",
      "year_resolved": "1985",
      "resolved_by": "Andrew Odlyzko and Herman te Riele",
      "verification": "computer-assisted",
      "formalization_notes": "Disproven via computational analysis of zeta zeros — no explicit counterexample n is known even today. A cautionary tale: extensive numerical evidence suggested it was true, and its truth would have implied the Riemann Hypothesis.",
      "prize": null,
      "codex_entry": "/mathematics/named-results/mertens-conjecture/",
      "sources": [
        "Odlyzko, A.M. and te Riele, H.J.J. (1985). Disproof of the Mertens conjecture. Journal für die reine und angewandte Mathematik, 357, 138-160."
      ]
    },
    {
      "id": "eulers-sum-of-powers-conjecture",
      "title": "Euler's Sum of Powers Conjecture",
      "statement_short": "At least n nth powers are needed to sum to an nth power (generalising Fermat).",
      "status": "disproven",
      "year_posed": "1769",
      "posed_by": "Leonhard Euler",
      "year_resolved": "1966",
      "resolved_by": "L.J. Lander and T.R. Parkin",
      "verification": "computer-assisted",
      "formalization_notes": "Disproven by direct computer search: 27^5 + 84^5 + 110^5 + 133^5 = 144^5. The published paper is famously only two sentences long.",
      "prize": null,
      "codex_entry": "/mathematics/named-results/eulers-sum-of-powers-conjecture/",
      "sources": [
        "Lander, L.J. and Parkin, T.R. (1966). Counterexample to Euler's conjecture on sums of like powers. Bulletin of the AMS, 72(6), 1079."
      ]
    }
  ],
  "last_updated": "2026-07-09"
}