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

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101120 of 266 problems
  • Whether the real Kalton-Peck space Z_2 is isomorphic to its hyperplanes. It is not: no hyperplane of Z_2 is isomorphic to Z_2, proved through a rank parity theorem for symplectic spaces applied to the Kalton-Swanson symplectic structure.

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    1 attempt

  • Real-Rootedness of Ehrhart h*-Polynomials at Large WidthGennadiy Averkov, Johannes Hofscheier, Benjamin Nill

    A question of Averkov, Hofscheier and Nill on whether the Ehrhart h^*-polynomial of a lattice polytope of large lattice width is real-rooted. Proved in fixed dimension for sufficiently large lattice width, giving strict log-concavity and…

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    1 attempt

  • Erdős Problem #321Paul Erdős, Ronald Graham, 1980

    What is the largest A⊆1,…,N such that all subset sums ∑_n∈ S1/n (over S⊆ A) are distinct?

    solved

    1 attempt · a verdict recorded from elsewhere

  • A convex body is in Faber-Krahn position if it minimizes the first Dirichlet eigenvalue within its volume-preserving linear orbit. The paper proves this position is unique up to orthogonal transformations, answering a question of…

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    1 attempt

  • Kuperberg's Six-Cylinder ConjectureWłodzimierz Kuperberg, 1990

    How many pairwise non-overlapping infinite circular cylinders of unit radius can simultaneously touch a unit ball? Kuperberg conjectured in 1990 that the maximum is six.

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    1 attempt

  • Zhu, Gyori, He, Lv, Salia and Xiao conjectured the maximum number of copies of a fixed cycle in an n-vertex graph of bounded circumference, attained by the join of a clique with an independent set. For every fixed s ≥ 3 and L ≥ 2s+2 and…

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    1 attempt

  • Sharp Hardness for MAX-3-CUTS. Khot, G. Kindler, E. Mossel, R. O'Donnell, 2004

    Assuming the Unique Games Conjecture, it is NP-hard to approximate MAX-3-CUT better than the Frieze-Jerrum semidefinite program does, and similarly for Quantum MAX-CUT: the sharpness question in the Khot-Kindler-Mossel-O'Donnell line,…

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  • Krauth and Mezard predicted in 1989 that the storage capacity of the Ising perceptron at zero margin is an explicit constant α_⋆ ≈ 0.8330786. Ding and Sun proved the matching lower bound and Huang the upper bound, but each was conditional…

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    1 attempt

  • Talagrand's Convexity ProblemMichel Talagrand, 1995

    Talagrand's convexity problem asks whether a universal number of Minkowski sum operations turns any set of large Gaussian measure into one containing a convex body of comparable measure. It is equivalent to a question about subgaussian…

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    1 attempt

  • For a perfect field k and a representation-infinite finite-dimensional k-algebra A, the Auslander–Reiten quiver of A has infinitely many connected components. This establishes a conjecture of Auslander, Reiten and Smalø, for…

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    1 attempt

  • Predicting Diagonalizability of a Mean MatrixYuheng Wu, Narayana Santhanam, 2024

    Wu and Santhanam asked whether one can determine, from an increasing i.i.d. sample of binary random matrices, whether the unknown mean matrix is diagonalizable, while making only finitely many errors almost surely. Answered affirmatively…

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  • For the switch-walk-switch lamplighter walk on Z_2 wr T_d, prove the sharp asymptotic p_2n(e,e) = ρ_d^2n exp[-(π^2 (log(d-1))^2 + o(1)) n/log^2 n] with ρ_d = frac2√d-1d.

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    1 attempt · a verdict recorded from elsewhere

  • The Modified Lyons–Sidorova Conjecture for Bounded-Variation PathsHoratio Boedihardjo; formulated systematically by Boedihardjo, Geng and Wang, after the original conjecture of Lyons and Sidorova, 2020

    For a continuous bounded-variation path with signature g, logarithmic signature l and increment v, the modified Lyons–Sidorova conjecture predicts the structure of g when R(l)=∞. The paper proves it: g=1 when v=0, and otherwise a prefix α…

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    1 attempt

  • Erdős Problem #690Paul Erdős, 1979

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

    solved

    1 attempt · a verdict recorded from elsewhere

  • A paper torus is an embedded polyhedral torus isometric to a flat torus. Schwartz proves no paper torus with 7 vertices exists and constructs one with 8, settling the minimum-vertex question in the flat-torus embedding tradition of…

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    1 attempt

  • Mixing Time of Kac's Walk on the Rotation GroupWalk introduced by W. K. Hastings; optimal rate the standing target of the mixing-time literature, 1970

    Kac's walk on the rotation group, introduced by Hastings in 1970, is a central high-dimensional Markov chain in statistical physics and computational science. The paper proves it mixes in n^2 log n steps, the conjectured optimal rate,…

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  • Zhi-Wei Sun conjectured a closed evaluation of a truncated Legendre-symbol determinant. For every prime p ≡ 3 pmod 4 it equals ⌊ (p-2)/3 ⌋^2 x, proved by reducing to inverse data for Chapman's full Legendre-symbol matrix and evaluating…

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  • A Universal Leading-Residue Formula for Witten Zeta FunctionsArising from Au's work on Witten zeta functions

    For an irreducible crystallographic root system of rank r with Coxeter number h, the paper proves that Au's normalized Witten zeta function has a simple pole at 2/h and evaluates its residue in closed form in terms of the Cartan…

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  • Oracle-Complexity Gap in Derivative-Free Convex OptimizationVladimir Protasov (gap since 1996), 1996

    For deterministically minimizing a convex 1-Lipschitz function on the d-dimensional ball using only exact function values, the query complexity sat between Ω(d) and O(d^2 log^2 d) since 1996. The paper proves a near-quadratic lower bound…

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  • The 4^k Barrier for the k-Distinct LanguageRan Ben-Basat, Ariel Gabizon & Meirav Zehavi, 2016

    Can the k-distinct language - words over [n] of length at most k with no repeated symbol - be recognized by an acyclic NFA of size c^k n^O(1) for some c < 4? A construction of size 2^1.96992k n^O(1) < 3.918^k n^O(1) answers yes.

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    1 attempt