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Related papers: Most $q$-matroids are not representable

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We classify all matroids with at most 8 elements that have the half-plane property, and we provide a list of some matroids on 9 elements that have, and that do not have the half-plane property. Furthermore, we prove that several classes of…

Combinatorics · Mathematics 2023-10-25 Mario Kummer , Büşra Sert

Matroids are often represented as oracles since there are no unified and compact representations for general matroids. This paper initiates the study of binary decision diagrams (BDDs) and zero-suppressed binary decision diagrams (ZDDs) as…

Combinatorics · Mathematics 2024-04-24 Hiromi Emoto , Yuni Iwamasa , Shin-ichi Minato

Solving a problem of Diestel and Pott, we construct a large class of infinite matroids. These can be used to provide counterexamples against the natural extension of the Well-quasi-ordering-Conjecture to infinite matroids and to show that…

Combinatorics · Mathematics 2013-01-28 Nathan Bowler , Johannes Carmesin

We develop the rudiments of a finite-dimensional representation theory of groups over idempotent semifields by considering linear actions on tropical linear spaces. This can be considered a tropical representation theory, a characteristic…

Representation Theory · Mathematics 2018-10-23 Noah Giansiracusa , Jacob Manaker

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

The connection between secret sharing and matroid theory is well established. In this paper, we generalize the concepts of secret sharing and matroid ports to $q$-polymatroids. Specifically, we introduce the notion of an access structure on…

Information Theory · Computer Science 2026-01-13 Johan Vester Dinesen , Eimear Byrne , Ragnar Freij-Hollanti , Camilla Hollanti

A Q-algebroid is a Lie superalgebroid equipped with a compatible homological vector field and is the infinitesimal object corresponding to a Q-groupoid. We associate to every Q-algebroid a double complex. As a special case, we define the…

Differential Geometry · Mathematics 2020-03-30 Rajan Amit Mehta

There has recently been ample interest in the question of which sets can be represented by linear matrix inequalities (LMIs). A necessary condition is that the set is rigidly convex, and it has been conjectured that rigid convexity is also…

Rings and Algebras · Mathematics 2012-04-18 Petter Brändén

Matroid theory is fundamentally connected with index coding and network coding problems. In fact, the reliance of linear index coding and network coding rates on the characteristic of a field has been demonstrated by using the two…

Information Theory · Computer Science 2024-07-18 Arman Sharififar , Parastoo Sadeghi , Neda Aboutorab

The theory of matroids or combinatorial geometries originated in linear algebra and graph theory, and has deep connections with many other areas, including field theory, matching theory, submodular optimization, Lie combinatorics, and total…

Combinatorics · Mathematics 2021-11-18 Federico Ardila

Efficient deterministic algorithms to construct representations of lattice path matroids over finite fields are presented. They are built on known constructions of hierarchical secret sharing schemes, a recent characterization of…

Combinatorics · Mathematics 2024-07-09 Carles Padró

We consider quiver representations respecting a quiver automorphism and show that the dimension vectors of the indecomposables are precisely the positive roots of an associated symmetrisable Kac-Moody Lie algebra. Moreover, every such Lie…

Representation Theory · Mathematics 2007-05-23 Andrew Hubery

In this paper we determine the representation type of some algebras of infinite matrices continuously controlled at infinity by a compact metrizable space. We explicitly classify their finitely presented modules in the finite and tame…

Representation Theory · Mathematics 2007-05-23 Fernando Muro

We prove that any irreducible $*$-representation of $\mathrm{Pol}(\mathrm{Mat}_n)_q$ can be 'lifted' to an irreducible *-representation of $\mathbb{C}[SU_{2n}]_q$, this result is then used to show the existence of the universal enveloping…

Quantum Algebra · Mathematics 2018-03-26 Olof Giselsson

We study the interplay between the lattice of F_{q^m}-subspaces and the lattice of F_{q^m}-subspaces of an F_{q^m}-vector space. Introducing notions of weight and defect relative to an F_q-subspace, we analyze the sequence of maximum…

Combinatorics · Mathematics 2025-09-30 Martino Borello , Olga Polverino , Ferdinando Zullo

The aim of this paper is to develop a $(q,m)$-polymatroidal approach to higher supports and higher rank-weight enumerators of rank-metric codes. In this framework, we establish analogs of several fundamental results known for matroids and…

Combinatorics · Mathematics 2026-05-25 Koji Imamura , Shinya Kawabuchi , Keisuke Shiromoto

This is a revised version of our original paper (arXiv:1808.00489v2) incorporating the corrections published in a corrigendum (arXiv:1808.00489v3). Our main theorem as originally stated was missing the required assumption that matroids…

Combinatorics · Mathematics 2025-05-28 Nathan Bowler , Daryl Funk , Daniel Slilaty

We consider the following \textit{network computation problem}. In an acyclic network, there are multiple source nodes, each generating multiple messages, and there are multiple sink nodes, each demanding a function of the source messages.…

Information Theory · Computer Science 2016-07-05 Anindya Gupta , B. Sundar Rajan

We raise the question of whether (a slightly generalized notion of) $qq$-characters can be constructed purely representation-theoretically. In the main example of the quantum toroidal $\mathfrak{gl}_1$ algebra, geometric engineering of…

Quantum Algebra · Mathematics 2022-11-28 Henry Liu

An infinite matroid is graphic if all of its finite minors are graphic and the intersection of any circuit with any cocircuit is finite. We show that a matroid is graphic if and only if it can be represented by a graph-like topological…

Combinatorics · Mathematics 2013-09-17 Nathan Bowler , Johannes Carmesin , Robin Christian