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Related papers: Theta rank, levelness, and matroid minors

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Recently, fundamental conditions on the sampling patterns have been obtained for finite completability of low-rank matrices or tensors given the corresponding ranks. In this paper, we consider the scenario where the rank is not given and we…

Machine Learning · Computer Science 2017-11-03 Morteza Ashraphijuo , Xiaodong Wang , Vaneet Aggarwal

It is possible to write the indicator function of any matroid polytope as an integer combination of indicator functions of Schubert matroid polytopes. In this way, every matroid on $n$ elements of rank $r$ can be thought of as a lattice…

Combinatorics · Mathematics 2025-08-14 Luis Ferroni , Alex Fink

Given vectors $v_1,\dots,v_n\in\mathbb{R}^d$ and a matroid $M=([n],I)$, we study the problem of finding a basis $S$ of $M$ such that $\det(\sum_{i \in S}v_i v_i^\top)$ is maximized. This problem appears in a diverse set of areas such as…

Data Structures and Algorithms · Computer Science 2020-04-20 Vivek Madan , Aleksandar Nikolov , Mohit Singh , Uthaipon Tantipongpipat

In this paper, we interpret the theta rank of an irreducible character of a finite classical group in terms of the data from the Lusztig classification. Then we prove the following two results: (1) the agreement of the $U$-rank and the…

Representation Theory · Mathematics 2021-10-20 Shu-Yen Pan

We provide upper and lower bounds on the smallest eigenvalue of grounded Laplacian matrices (which are matrices obtained by removing certain rows and columns of the Laplacian matrix of a given graph). The gap between the upper and lower…

Combinatorics · Mathematics 2014-07-08 Mohammad Pirani , Shreyas Sundaram

This paper considers the topological degree of $G$-shifts of finite type for the case where $G$ is a nonabelian monoid. Whenever the Cayley graph of $G$ has a finite representation and the relationships among the generators of $G$ are…

Dynamical Systems · Mathematics 2018-08-27 Jung-Chao Ban , Chih-Hung Chang , Nai-Zhu Huang

We show that a generic principally polarized abelian variety (ppav) is uniquely determined by its theta hyperplanes. These are the non-projectivized version of those studied by Caporaso and Sernesi (see math.AG/0204164), which in a sense…

Algebraic Geometry · Mathematics 2007-05-23 Samuel Grushevsky , Riccardo Salvati Manni

The square root rank of a nonnegative matrix $A$ is the minimum rank of a matrix $B$ such that $A=B \circ B$, where $\circ$ denotes entrywise product. We show that the square root rank of the slack matrix of the correlation polytope is…

Computational Complexity · Computer Science 2014-11-26 Troy Lee , Zhaohui Wei

We derive the explicit formula for the inverse of zeta matrix for any graded posets with the finite set of minimal elements . The combinatorial interpretation of this result is given. For that to do special number theoretic code triangles…

Combinatorics · Mathematics 2011-05-19 A. K. Kwasniewski

We consider three matroids defined by Kalai in 1985: the symmetric completion matroid $\mathcal{S}_d$ on the edge set of a looped complete graph; the hyperconnectivity matroid $\mathcal{H}_d$ on the edge set of a complete graph; and the…

Combinatorics · Mathematics 2026-03-17 Dániel Garamvölgyi , Bill Jackson , Tibor Jordán , Soma Villányi

The topological zeta function of a matroid is a rational function as well as a valuative invariant of the matroid, encoding rich combinatorial information. We analyze topological zeta functions of matroids from the vantage point of several…

Combinatorics · Mathematics 2026-05-11 Dawit Mengesha , Robert Miranda , Brian Sun

The tensor train (TT) rank has received increasing attention in tensor completion due to its ability to capture the global correlation of high-order tensors ($\textrm{order} >3$). For third order visual data, direct TT rank minimization has…

Computer Vision and Pattern Recognition · Computer Science 2020-04-30 Meng Ding , Ting-Zhu Huang , Xi-Le Zhao , Michael K. Ng , Tian-Hui Ma

Frame matroids and lifted-graphic matroids are two distinct minor-closed classes of matroids, each of which generalises the class of graphic matroids. The class of quasi-graphic matroids, recently introduced by Geelen, Gerards, and Whittle,…

Combinatorics · Mathematics 2017-06-21 Daryl Funk , Dillon Mayhew

Motivated by problems in algebraic complexity theory (e.g., matrix multiplication) and extremal combinatorics (e.g., the cap set problem and the sunflower problem), we introduce the geometric rank as a new tool in the study of tensors and…

Computational Complexity · Computer Science 2023-04-27 Swastik Kopparty , Guy Moshkovitz , Jeroen Zuiddam

The holonomic rank of the A-hypergeometric system M_A(\beta) is the degree of the toric ideal I_A for generic parameters; in general, this is only a lower bound. To the semigroup ring of A we attach the ranking arrangement and use this…

Algebraic Geometry · Mathematics 2019-02-20 Christine Berkesch

Littlewood--Offord Problem concerns the number of subsums of a set of vectors that fall in a given convex set. We present a discrete variation of this problem where we estimate the number of subsums that are $(0,1)$-vectors. We then utilize…

Combinatorics · Mathematics 2024-01-23 Hossein Esmailian , Ebrahim Ghorbani

A matroid base polytope is a polytope in which each vertex has 0,1 coordinates and each edge is parallel to a difference of two coordinate vectors. Matroid base polytopes are described combinatorially by integral submodular functions on a…

Combinatorics · Mathematics 2025-11-19 Jonah Berggren , Jeremy L. Martin , José A. Samper

Given a graph G, a real orthogonal representation of G is a function from its set of vertices to R^d such that two vertices are mapped to orthogonal vectors if and only if they are not neighbors. The minimum vector rank of a graph is the…

Combinatorics · Mathematics 2013-04-16 Xiaowei Li , Michael Nathanson , Rachel Phillips

A biased graph is a graph with a class of selected circles ("cycles", "circuits"), called "balanced", such that no theta subgraph contains exactly two balanced circles. A biased graph has two natural matroids, the frame matroid and the lift…

Combinatorics · Mathematics 2021-06-16 Rigoberto Flórez , Thomas Zaslavsky

We characterize a rich class of valuated matroids, called R-minor valuated matroids that includes the indicator functions of matroids, and is closed under operations such as taking minors, duality, and induction by network. We exhibit a…

Combinatorics · Mathematics 2024-11-27 Edin Husić , Georg Loho , Ben Smith , László A. Végh