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We give a self-contained proof of the strongest version of Mason's conjecture, namely that for any matroid the sequence of the number of independent sets of given sizes is ultra log-concave. To do this, we introduce a class of polynomials,…

Combinatorics · Mathematics 2018-11-06 Nima Anari , Kuikui Liu , Shayan Oveis Gharan , Cynthia Vinzant

We consolidate two widely believed conjectures about tautologies -- no optimal proof system exists, and most require superpolynomial size proofs in any system -- into a $p$-isomorphism-invariant condition satisfied by all paddable…

Computational Complexity · Computer Science 2022-07-21 Hunter Monroe

We use the equivariant cohomology ring of the permutohedral variety to study matroids and their invariants. Investigating the pushforward of matroid Chern classes defined by A. Berget, C. Eur, H. Spink and D. Tseng to the product space…

Algebraic Geometry · Mathematics 2025-09-25 Mario Bauer , Matěj Doležálek , Magdaléna Mišinová , Semen Słobodianiuk , Julian Weigert

Chow rings of matroids were instrumental in the resolution of the Heron-Rota-Welsh Conjecture by Adiprasito, Huh, and Katz and in the resolution of the Top-Heavy Conjecture by Braden, Huh, Matherne, Proudfoot, and Wang. The Chow ring of a…

Commutative Algebra · Mathematics 2022-12-13 Matthew Mastroeni , Jason McCullough

The weighted transition polynomial of a multimatroid is a generalization of the Tutte polynomial. By defining the activity of a skew class with respect to a basis in a multimatroid, we obtain an activities expansion for the weighted…

Combinatorics · Mathematics 2025-02-24 Criel Merino , Iain Moffatt , Steven Noble

Let $R=\mathcal{O}_{\Q(\sqrt{d})}$ for $d<0$, squarefree, $d\neq -1,-3$. We prove Lehmer's conjecture for associated reciprocal polynomials of $R$-matrices; that is, any noncyclotomic $R$-matrix has Mahler measure at least…

Number Theory · Mathematics 2011-03-24 G. Taylor

The planar solution is discussed for an N=3 Chern-Simons-matter theory constructed recently by Gaiotto and Tomasiello. The planar resolvent is obtained in terms of contour integrals. If the sum of two Chern-Simons levels k_1,k_2 is small,…

High Energy Physics - Theory · Physics 2010-11-11 Takao Suyama

We give a general multiplication-convolution identity for the multivariate and bivariate rank generating polynomial of a matroid. The bivariate rank generating polynomial is transformable to and from the Tutte polynomial by simple algebraic…

Combinatorics · Mathematics 2009-09-15 Joseph P. S. Kung

For {\theta} \in [0, 2{\pi}), consider the rotation matrix R? and h = ({\lambda}, 0; 0, 0), {\lambda} > 1. Let W_n({\theta}) denote the product of m R?'s and n h's with the condition m \leq [\epsilon\astn], (0 < \epsilon < 1). We analyze…

Dynamical Systems · Mathematics 2011-06-16 Jeffrey Allen , Benjamin Seeger , Deborah Unger

The study of matroid products traces back to the 1970s, when Lov\'asz and Mason studied the existence of various types of matroid products with different strengths. Among these, the tensor product is arguably the most important, which can…

We provide a formula for the Poincar\'e dual of the Chern-Schwartz-MacPherson (CSM) cycle of a matroid in the Chow ring of the matroid. We derive the formula from the case of matroids realizable over the complex numbers and prove that it…

Combinatorics · Mathematics 2024-11-15 Franquiz Caraballo Alba , Jeffery Liu

The trimaximal mixing scheme (TM$_2$) results in \textit{``magic"} neutrino mass matrix ($M_\nu$) which is known to accommodate neutrino oscillation data. In this paper, we propose a phenomenological ansatz for $M_\nu$ by extending the…

High Energy Physics - Phenomenology · Physics 2023-06-28 Labh Singh , Tapender , Monal Kashav , Surender Verma

Recently, it was proved by Anari-Oveis Gharan-Vinzant, Anari-Liu-Oveis Gharan-Vinzant and Br\"{a}nd\'{e}n-Huh that, for any matroid $M$, its basis generating polynomial and its independent set generating polynomial are log-concave on the…

Combinatorics · Mathematics 2020-03-24 Satoshi Murai , Takahiro Nagaoka , Akiko Yazawa

We generalize the Tutte polynomial of a matroid to a morphism of matroids via the K-theory of flag varieties. We introduce two different generalizations, and demonstrate that each has its own merits, where the trade-off is between the ease…

Combinatorics · Mathematics 2021-01-19 Rodica Dinu , Christopher Eur , Tim Seynnaeve

Let $ E $ be a possibly infinite set and let $ M $ and $ N $ be matroids defined on $ E $. We say that the pair $ \{ M,N \} $ has the Intersection property if $ M $ and $ N $ share an independent set $ I $ admitting a bipartition $…

Combinatorics · Mathematics 2021-06-11 Attila Joó

We associate to every matroid M a polynomial with integer coefficients, which we call the Kazhdan-Lusztig polynomial of M, in analogy with Kazhdan-Lusztig polynomials in representation theory. We conjecture that the coefficients are always…

Combinatorics · Mathematics 2016-07-04 Ben Elias , Nicholas Proudfoot , Max Wakefield

We prove that for every proper minor-closed class $M$ of matroids representable over a prime field, there exists a constant-competitive matroid secretary algorithm for the matroids in $M$. This result relies on the extremely powerful…

Combinatorics · Mathematics 2019-10-03 Tony Huynh , Peter Nelson

We provide explicit combinatorial formulas for the Chow polynomial and for the augmented Chow polynomial of uniform matroids, thereby proving a conjecture by Ferroni. These formulas refine existing formulas by Hampe and by Eur, Huh, and…

Combinatorics · Mathematics 2024-12-02 Elena Hoster

We investigate complement-finite submonoids of the monoid of nonnegative integer points of a unipotent linear algebraic group $G$. These monoids are in general noncommutative but they specialize to the generalized numerical monoids of…

Group Theory · Mathematics 2023-06-12 Mahir Bilen Can , Naufil Sakran

We show that, if $\alpha > 0$ is a real number, $n \ge 2$ and $\ell \ge 2$ are integers, and $q$ is a prime power, then every simple matroid $M$ of sufficiently large rank, with no $U_{2,\ell}$-minor, no rank-$n$ projective geometry minor…

Combinatorics · Mathematics 2012-10-17 Jim Geelen , Peter Nelson
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