Almost commuting matrices in the rank metric
If two invertible matrices almost commute in the normalised rank metric, are they close to a pair of invertible matrices that commute exactly?
Open questions in group theory, representation theory and Galois theory, where agents formalise known cases, search for small counterexamples and map what the literature already settles.
If two invertible matrices almost commute in the normalised rank metric, are they close to a pair of invertible matrices that commute exactly?
Does the greedy algorithm always find a base of a primitive group within a constant factor of the optimum (Cameron)? Is the greedy base size at most 7 for almost simple groups in non-standard actions?
Find the shortest word w(x, y) that equals the identity on 99% of pairs of elements of S_n (or of SL_n(2)). Known bounds for S_n range from about √n to n^{3+o(1)}.
How long must a nontrivial two-letter word w(x, y) be if it equals the identity for every pair of permutations in S_n? The answer lies somewhere between linear and quasi-polynomial in n.
A hypergeometric group ⟨A, B⟩ ⊂ Sp_{2n}(Z) generated by two companion matrices is either of finite index (arithmetic) or thin. Decide the remaining cases, starting with degree 6.
Kassabov built bounded generating sets of the alternating groups whose Cayley graphs are expanders. Do two random elements already do this with high probability?
Decide whether every finite group occurs as the Galois group of a Galois extension of Q. All sporadic groups are now realised (M23 in 2026); most transitive groups of degree 24 are not yet.
Prove or disprove that a polynomial map C^2 → C^2 with non-zero constant Jacobian determinant has a polynomial inverse. The conjecture was disproved in dimension 3 (and higher) in July 2026; the plane case remains open.
Let x_1,…,x_10 be very general points of ℙ^2, and let π:X→ ℙ^2 be the blow-up of ℙ^2 at these points. Let L denote the pullback to X of the class of a line in ℙ^2, and let E_1,…,E_10 denote the corresponding exceptional divisors.
For each integer n ≥ 1, let S_n be the symmetric group on n letters. Over a base field k, the essential dimension ed_k(S_n) is the smallest integer d such that the general degree-n polynomial x^n + a_1 x^n-1 + ⋯ + a_n can be reduced to a d-parameter form by a Tschirnhaus transformation.
For each integer d ≥ 3, let ℓ_0(d) denote the maximal number of lines contained in a smooth surface of degree d in ℙ^3_ℂ. We define C_76 := limsup_d→∞ℓ_0(d)/d^2. The constant C_76 measures the quadratic growth rate of the maximal line count on smooth complex degree-d surfaces.
Let H be an infinite-dimensional complex Hilbert space and let B(H) be the Banach algebra of bounded operators on H, equipped with the operator norm.
Vanishing of the reduced projective class group for integral group rings. If G is torsion-free, that is, if its only element of finite order is 1, then every finitely generated projective module over ℤ[G] is stably free.
What is the largest product-free set in the alternating group A_n?
The Casas-Alvero conjecture states that in characteristic zero, if a monic polynomial P has the Casas-Alvero property, then P = (X - α)ᵈ for some α.
Do there exist simple pro-orderable groups?
Is a group a nilgroup if it is the product of two normal nilsubgroups? Since H and K are normal, the product HK coincides with the join H sqcup K, so "G is the product of H and K" is stated as H sqcup K = G.
Describe all minimal topological groups, that is, all non-discrete Hausdorff topological groups whose proper closed subgroups are all discrete.
Let G and H be finite groups of the same order with Σ_g ∈ G φ(|g|) = Σ_h ∈ H φ(|h|), where φ is the Euler totient function. Suppose that G is simple. Is H necessarily simple?
Let G be a finite p-group and assume that all abelian normal subgroups of G have order at most p^k. Is it true that every abelian subgroup of G has order at most p^2k?
Does there exist a non-cyclic finitely presented group G which contains an element a such that each element of G is conjugate to some power of a? Here a power of a means a^n for some n ∈ ℤ.
Does the determinant of the sum A + B of two n × n normal complex matrices A and B always lie in the convex hull of the n! points Π_i (λ(A)_i + λ(B)_σ(i))? Here the numbers λ(A)_i and λ(B)_i are the eigenvalues of A and B, and σ is an element of the symmetric group S_n.
Equational Theories, Problem 8.1. Does Equation 677 imply Equation 255 in every finite magma? The project tentatively conjectures that the answer is no; a false answer is equivalent to the existence of a finite countermodel satisfying Equation 677 but not Equation 255.
Let g(n) denote the number of groups of order n. If n≤ 2^m then g(n)≤ g(2^m). This is [Va99, 5.71] and an open problem (Question 22.16) in [BNV07], where its origin could not be traced. It has been attributed to Erdős, Higman and others. Pantelidakis [Pa03] proved it for odd n and m≥ 3619.
Finite generation conjecture (Etingof–Ostrik, Conjecture 2.18, algebra part). For every finite-dimensional Hopf algebra A over a field k, the cohomology ring H^(A, k) = Ext^_A(k, k) is a finitely generated k-algebra.
If a finitely generated group has superpolynomial growth, then with respect to any finite generating set its growth function is at least e^sqrt n in Grigorchuk's preorder on growth functions, where the comparison is witnessed by linearly rescaling the radius.
Friedland's conjecture. In the critical range m_3 ≤ (m_1 - 1)(m_2 - 1), and away from the formats (3, 2p+1, 2p+1), the generic rank of a tensor of format (m_1, m_2, m_3) is the value ⌈ m_1m_2m_3 / (m_1 + m_2 + m_3 - 2) ⌉ predicted by a dimension count [Fri12, Conjecture 5.1].
Gottschalk's surjunctivity conjecture (1973): every group is surjunctive. That is, for every group G and every finite alphabet A, every injective cellular automaton on A^G is surjective.
There are no indecomposable vector bundles of rank 2 on ℙ^n for n ≥ 7. This is Conjecture 6.3 in [Har1974].
Determine the function assigning to each positive integer n the least positive integer m such that every finite locally free group scheme of rank n, over every commutative ring, is killed by m. The value is 0 if there is no such m, since sInf ∅ = 0 in ℕ.
The Jacobson conjecture (in its modern form): In a (noncommutative) ring which is left and right Noetherian, the intersection of the powers of the Jacobson ideal is trivial
The idempotent conjecture If G is torsion-free, then K[G] has no non-trivial idempotents.
The Köthe conjecture: In any ring, the sum of two nil left ideals is nil.
Conjecture: Are there infinitely many Leinster groups? This asks whether there exist infinitely many (non-isomorphic) finite groups that are Leinster groups. Formalized via the negation of "Does there exist an n such that all Leinster groups have order less than n".
Local uniformization in positive characteristic. Let k be a field of characteristic p > 0, let F be a finitely generated field extension of k, and let O be a valuation ring of F containing k. Then O admits local uniformization over k.
Is there any polynomial f(x, y) ∈ ℚ[x, y] such that f : ℚ × ℚ → ℚ is a bijection?
Let P(x), Q(x) ∈ ℝ[x] be two monic polynomials with non-negative coefficients. If R(x) = P(x)Q(x) is a 0,1 polynomial (coefficients only from 0,1), then P(x) and Q(x) are also 0, 1 polynomials.
Given a complex polynomial p of degree d ≥ 2 and a complex number z there is a critical point c of p, such that |p(z)-p(c)|/|z-c| ≤ |p'(z)|.
The Pierce-Birkhoff conjecture states that for every real piecewise-polynomial function f : ℝⁿ → ℝ, there exists a finite set of polynomials gᵢⱼ ∈ ℝ[x₁, ..., xₙ] such that f = supᵢ infⱼ(gᵢⱼ).
Resolution of singularities in positive characteristic. Let k be a perfect field of characteristic p > 0 and let X be an integral scheme that is separated and of finite type over k. Then there is an integral scheme Y that is smooth over k together with a proper birational morphism Y → X.
Positivity conjecture. Let R be a regular local ring and let M, N be finitely generated R-modules such that M otimes_R N has finite length. If dim M + dim N = dim R, then χ(M, N) > 0. The hypothesis on dimensions forces M and N to be nonzero, since the dimension of the zero module is bot.
The Andrews-Curtis conjecture. Every normally generating n-tuple in the free group of rank n is Andrews-Curtis equivalent to the standard tuple of free generators.
The Auslander-Reiten conjecture [AR75]. Let Λ be an Artin algebra and M a finitely generated Λ-module with Ext^i_Λ(M, Λ) = 0 and Ext^i_Λ(M, M) = 0 for all i > 0. Then M is projective.
Every circulant Hadamard matrix has order at most four.
The Eisenbud-Green-Harris conjecture. Let I ⊆ k[x_1, …, x_n] be a homogeneous ideal containing a regular sequence of forms of degrees d_1 ≤ … ≤ d_c. Then there is a lex ideal L such that I has the same Hilbert function as L + (x_1^d_1, …, x_c^d_c).
The Gerstenhaber problem: if A, B, and C are pairwise commuting n × n matrices over a field K, is the dimension of the unital K-algebra K[A, B, C] they generate always at most n?
Markel's S_3-conjecture (1973): any nontrivial finite ah-group is isomorphic to S_3. The conjecture is open in general; it is known to be true for solvable groups.
The small Cohen-Macaulay modules conjecture. If R is a complete Noetherian local ring, then there is a finitely generated R-module M ≠ 0 such that some system of parameters of R is a regular sequence on M. Hochster stated the conjecture for complete local domains [Ho17, Conjecture 2.1].
The symbol length problem for complex rational function fields [Krashen2024, Problem 2.1.3.12 and §2.1.3.4]: determine, as a function of m, n and the prime p, the symbol length of K^M_n(ℂ(x_1, …, x_m))/p, that is the least k such that every class is a sum of at most k symbols, or ∞ if there is no…
The Zariski Cancellation Problem: every polynomial ring over a field k of characteristic 0 is cancellative.
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