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Related papers: The minimum rank problem over finite fields

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The minimum rank problem for a (simple) graph $G$ is to determine the smallest possible rank over all real symmetric matrices whose $ij$th entry (for $i\neq j$) is nonzero whenever $\{i,j\}$ is an edge in $G$ and is zero otherwise. This…

Combinatorics · Mathematics 2014-10-09 Shaun Fallat , Leslie Hogben

For a simple graph, the minimum rank problem is to determine the smallest rank among the symmetric matrices whose off-diagonal nonzero entries occur in positions corresponding to the edges of the graph. Bounds on this minimum rank (and on…

Combinatorics · Mathematics 2025-11-03 Louis Deaett , Derek Young

We provide a counterexample to a recent conjecture that the minimum rank of every sign pattern matrix can be realized by a rational matrix. We use one of the equivalences of the conjecture and some results from projective geometry. As a…

Combinatorics · Mathematics 2007-09-18 Swastik Kopparty , K. P. S. Bhaskara Rao

The minimum rank problem is to determine for a graph $G$ the smallest rank of a Hermitian (or real symmetric) matrix whose off-diagonal zero-nonzero pattern is that of the adjacency matrix of $G$. Here $G$ is taken to be a circulant graph,…

Combinatorics · Mathematics 2015-11-26 Louis Deaett , Seth A. Meyer

Recently, there have been found new relations between the zero forcing number and the minimum rank of a graph with the algebraic co-rank. We continue on this direction by giving a characterization of the graphs with real algebraic co-rank…

Combinatorics · Mathematics 2020-05-06 Carlos A. Alfaro

Our main result is a sharp bound for the number of vertices in a minimal forbidden subgraph for the graphs having minimum rank at most 3 over the finite field of order 2. We also list all 62 such minimal forbidden subgraphs. We conclude by…

Combinatorics · Mathematics 2008-09-03 Wayne Barrett , Jason Grout , Raphael Loewy

The minimum rank of a graph G is the minimum rank over all real symmetric matrices whose off-diagonal sparsity pattern is the same as that of the adjacency matrix of G. In this note we present the first exact algorithm for the minimum rank…

Combinatorics · Mathematics 2019-12-03 Boris Brimkov , Zachary Scherr

Fractional minimum positive semidefinite rank is defined from $r$-fold faithful orthogonal representations and it is shown that the projective rank of any graph equals the fractional minimum positive semidefinite rank of its complement. An…

Combinatorics · Mathematics 2018-01-04 Leslie Hogben , Kevin F. Palmowski , David E. Roberson , Simone Severini

In this paper we deal with two aspects of the minimum rank of a simple undirected graph $G$ on $n$ vertices over a finite field $\FF_q$ with $q$ elements, which is denoted by $\mr(\FF_q,G)$. In the first part of this paper we show that the…

Combinatorics · Mathematics 2010-07-21 Shmuel Friedland , Raphael Loewy

The minimum rank of a simple graph $G$ is defined to be the smallest possible rank over all symmetric real matrices whose $ij$th entry (for $i\neq j$) is nonzero whenever $\{i,j\}$ is an edge in $G$ and is zero otherwise. Minimum rank is a…

Combinatorics · Mathematics 2008-12-05 Laura DeLoss , Jason Grout , Leslie Hogben , Tracy McKay , Jason Smith , Geoff Tims

This work investigates the structure of rank-metric codes in connection with concepts from finite geometry, most notably the $q$-analogues of projective systems and blocking sets. We also illustrate how to associate a classical…

Combinatorics · Mathematics 2021-06-24 Gianira N. Alfarano , Martino Borello , Alessandro Neri , Alberto Ravagnani

A vertex k-ranking is a labeling of the vertices of a graph with integers from 1 to k so any path connecting two vertices with the same label will pass through a vertex with a greater label. The rank number of a graph is defined to be the…

Combinatorics · Mathematics 2015-03-20 Sitan Chen

We study the collection of group structures that can be realized as a group of rational points on an elliptic curve over a finite field (such groups are well known to be of rank at most two). We also study various subsets of this collection…

Number Theory · Mathematics 2010-03-16 William D. Banks , Francesco Pappalardi , Igor E. Shparlinski

The minimum skew rank $mr^{-}(\mathbb{F},G)$ of a graph $G$ over a field $\mathbb{F}$ is the smallest possible rank among all skew symmetric matrices over $\mathbb{F}$, whose ($i$,$j$)-entry (for $i\neq j$) is nonzero whenever $ij$ is an…

Combinatorics · Mathematics 2017-02-10 Yanna Wang , Bo Zhou

A frame template over a field $\mathbb F$ describes the precise way in which a given $\mathbb F$-representable matroid is close to being a frame matroid. Our main result determines the maximum-rank projective or affine geometry that is…

Combinatorics · Mathematics 2021-11-10 Peter Nelson , Zach Walsh

We present old and recent results on rank problems and linearizability of geodesic planar webs.

Differential Geometry · Mathematics 2008-12-03 Vladislav V. Goldberg , Valentin V. Lychagin

The minrank of a graph $G$ on the set of vertices $[n]$ over a field $\mathbb{F}$ is the minimum possible rank of a matrix $M\in\mathbb{F}^{n\times n}$ with nonzero diagonal entries such that $M_{i,j}=0$ whenever $i$ and $j$ are distinct…

Combinatorics · Mathematics 2019-01-29 Noga Alon , Igor Balla , Lior Gishboliner , Adva Mond , Frank Mousset

A vertex ranking of a graph is an assignment of ranks (or colors) to the vertices of the graph, in such a way that any simple path connecting two vertices of equal rank, must contain a vertex of a higher rank. In this paper we study a…

Combinatorics · Mathematics 2016-09-21 Ilan Karpas , Ofer Neiman , Shakhar Smorodinsky

We study the minimum rank of a (simple, undirected) graph, which is the minimum rank among all matrices in a space determined by the graph. We determine the exact set of graphs on eight vertices for which the nullity of a minimum rank…

Combinatorics · Mathematics 2025-06-13 Wayne Barrett , Mark Hunnell , John Hutchens , John Sinkovic

A graph G is called "minimalizable" if a diagram with minimal crossing number can be obtained from an arbitrary diagram of G by crossing changes. If, furthermore, the minimal diagram is unique up to crossing changes then G is called…

Geometric Topology · Mathematics 2007-05-23 J. Sawollek
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