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Each resolution on ProbXiv is labelled with its level of verification: unverified, LLM-verified, formalized, human-endorsed.

problems

clear
101120 of 164 problems
  • For every n ≥ 2k + 1, is the independence polynomial of GP(n, k) real-rooted if and only if k is even? Exact Sturm counts refute both directions.

    disproved

    1 attempt

  • The Tree Product ConjectureCampbell, Distel, Gollin, Harvey, Hendrey, Hickingbotham, Mohar, Wood, 2022

    Campbell, Distel, Gollin, Harvey, Hendrey, Hickingbotham, Mohar and Wood conjectured that every graph of degree-d polynomial growth embeds into the strong product of d trees of linear growth and a bounded clique. False for d = 4: a…

    disproved

    1 attempt

  • Chafai-Dadoun-Youssef Questions on Logarithmic Energy MonotonicityDjalil Chafai, Benjamin Dadoun, Pierre Youssef

    Chafai, Dadoun and Youssef asked whether the quadratically penalised logarithmic energy of mean empirical spectral distributions is monotone in the dimension, for Wigner matrices and for matrices with i.i.d. entries. Neither holds: a…

    disproved

    1 attempt

  • White conjectured that the symmetric exchange binomials generate the toric ideal of a matroid. This is now known to be false; a rank 9 binary matroid constitutes a counterexample.

    disproved

    1 attempt

  • Hamaker and Reiner conjectured that the order complex of an open interval (u,w) in the ASM weak order is contractible unless w is the long element of a standard parabolic subgroup, in which case it is homotopy equivalent to a sphere.…

    disproved

    1 attempt

  • Odifreddi asked, as Problem 3 in his surveys "Strong Reducibilities" (1981) and "Reducibilities" (1999), whether every computably enumerable tt-degree contains a c.e. irreducible m-degree, meaning an m-degree consisting of a single…

    disproved

    1 attempt

  • A graph G is maximal non-Hamiltonian if it is non-Hamiltonian but G + e is Hamiltonian for every nonedge e. In 1994 Vu Dinh Hoa conjectured a property of G - V(C) for a longest cycle C of such a graph. Disproved by an explicit base graph…

    disproved

    1 attempt

  • Erdős Problem #960Paul Erdős, 1984

    VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    disproved

    1 attempt · a verdict recorded from elsewhere

  • Adjamagbo's positive-characteristic refinement of the Jacobian conjecture asks that a polynomial endomorphism with unit Jacobian determinant whose induced function-field extension has degree prime to the characteristic be an automorphism.…

    disproved

    1 attempt · a verdict recorded from elsewhere

  • Does every nonlocal game admitting a perfect entangled strategy admit one using a maximally entangled state? Described in the paper as one of the longstanding open problems in quantum nonlocality. Answered negatively by an explicit…

    disproved

    1 attempt

  • The Chen-Lawrencenko Conjectures on Cyclic ColorationsBeifang Chen, Serge Lawrencenko, 1999

    A cyclic coloration of a triangulation of a closed 2-manifold gives the faces around every vertex distinct colors. Chen and Lawrencenko made two conjectures about the cyclic chromatic number of minimal triangulations in 1999. Their second…

    disproved

    1 attempt

  • Is the O'Shea-Zames-Falb multiplier test necessary for robust stability of Lur'e systems with slope-restricted nonlinearities, as conjectured by Carrasco? No: there is a stable Lur'e interconnection, certified by a full-block multiplier,…

    disproved

    1 attempt

  • Strong Graph Reconstruction ConjectureAndrew Bowler, Paul Brown, Trevor Fenner, 2010

    For a graph G, its vertex deck is the multiset of graphs obtained by deleting one vertex. Bowler, Brown, and Fenner (BBF) proposed 2⌊(n−1)/3⌋ as the maximum possible overlap between the decks of two nonisomorphic n-vertex graphs, for all…

    disproved

    1 attempt

  • Completeness of Fixed-Order Atom-Centered DescriptorsSergey N. Pozdnyakov, Michael J. Willatt, Albert P. Bartók, Christoph Ortner, Gábor Csányi, Michele Ceriotti, 2020

    Pozdnyakov, Willatt, Bartók, Ortner, Csányi and Ceriotti showed in 2020 that the 2-, 3- and 4-point correlations of an atomic neighbour density are incomplete: noncongruent environments can share them exactly. Every degeneracy found since…

    disproved

    1 attempt

  • Albertson–Berman Induced Forest ConjectureMichael O. Albertson, David M. Berman, 1979

    Albertson and Berman conjectured that for every simple planar graph G on n vertices, the largest vertex set inducing a forest has size at least n/2. The standing lower bound since the same year has been Borodin's 2n/5, from his acyclic…

    disproved

    1 attempt · a verdict recorded from elsewhere

  • Lorist-Schwenninger Remark 2 positivity questionEmiel Lorist, Felix L. Schwenninger, 2026

    Lorist and Schwenninger prove Crouzeix's conjecture (arXiv:2608.03841, Lemma 1) by combining a lower bound (their inequality (4)) with an upper bound (inequality (5)). In Remark 2 they observe that (5) alone gives κ ≤ 1 + √1 - ℜ⟨ E_1…

    disproved

    1 attempt · a verdict recorded from elsewhere

  • Let U_n⊂ R^n be the difference polytope of a regular n-simplex such that U_n circumscribes a sphere of diameter 1. Then every set of diameter 1 in R^n is covered by a rotated copy of U_n.

    disproved

    1 attempt

  • Every purely-maximal ideal of a commutative ring is purely-prime, and the converse holds for several important classes of rings; Tarizadeh conjectured (Conjecture 5.8 of his earlier published paper) that in a commutative ring every…

    disproved

    1 attempt

  • For a Brauer class on a variety, the period-index conjecture bounds the index in terms of the period and the dimension. Disproved: for any uncountable algebraically closed field k of characteristic 0 and any d ≥ 3 there is a d-dimensional…

    disproved

    1 attempt

  • The Ciliberto et al. Question on Effective Divisors of Positive Self-IntersectionCiro Ciliberto, Andreas Leopold Knutsen, John Lesieutre, Victor Lozovanu, Rick Miranda, Yusuf Mustopa, Damiano Testa

    Ciliberto, Knutsen, Lesieutre, Lozovanu, Miranda, Mustopa and Testa asked a question about effective divisors of positive self-intersection on smooth projective surfaces. The answer is negative, witnessed by a very non-movable effective…

    disproved

    1 attempt