English
Related papers

Related papers: Fusion rules for pastures and tracts

200 papers

Given two finite matroids on the same ground set, a celebrated result of Edmonds says that the ground set can be partitioned into two disjoint subsets in a manner that there is a common independent set in both matroids whose intersection…

Combinatorics · Mathematics 2025-01-27 Irfan Alam

With a simple generic approach, we develop a classification that encodes and measures the strength of completeness (or compactness) properties in various types of spaces and ordered structures. The approach also allows us to encode notions…

General Topology · Mathematics 2020-12-01 Hanna Ćmiel , Franz-Viktor Kuhlmann , Katarzyna Kuhlmann

We give completely combinatorial proofs of the main results of [3] using polygons. Namely, we prove that the mapping class group of a surface with boundary acts faithfully on a finitely-generated linear category. Along the way we prove some…

Geometric Topology · Mathematics 2011-08-19 Kyler Siegel

We explore a combinatorial theory of linear dependency in complex space, "complex matroids", with foundations analogous to those for oriented matroids. We give multiple equivalent axiomatizations of complex matroids, showing that this…

Combinatorics · Mathematics 2013-03-27 Laura Anderson , Emanuele Delucchi

Using the framework of pastures and foundations of matroids developed by Baker-Lorscheid, we give algorithms to: (i) compute the foundation of a matroid, and (ii) compute all morphisms between two pastures. Together, these provide an…

Combinatorics · Mathematics 2023-07-27 Tianyi Zhang , Justin Chen

As part of the recent developments in infinite matroid theory, there have been a number of conjectures about how standard theorems of finite matroid theory might extend to the infinite setting. These include base packing, base covering, and…

Combinatorics · Mathematics 2012-03-06 Nathan Bowler , Johannes Carmesin

In this paper, the structural controllability of the systems over F(z) is studied using a new mathematical method-matroids. Firstly, a vector matroid is defined over F(z). Secondly, the full rank conditions of [sI-A|B] are derived in terms…

Systems and Control · Computer Science 2017-04-04 Yupeng Yuan , Zhixiong Li , Malekian Reza , Yongzhi Chen , Ying Chen

In our previous papers, together with J. Paseka we introduced so-called sectionally pseudocomplemented lattices and posets and illuminated their role in algebraic constructions. We believe that - similar to relatively pseudocomplemented…

Logic · Mathematics 2020-07-28 Ivan Chajda , Helmut Länger

We prove that the bundles with flat connections on configuration spaces associated to braided fusion categories, as well as the bundles with flat connections on moduli spaces of curves (conformal blocks) associated to modular fusion…

Algebraic Geometry · Mathematics 2025-09-24 Pierre Godfard

We propose a conjectural extension to positive characteristic case of a well known Deligne's theorem on the existence of super fiber functors. We prove our conjecture in the special case of semisimple categories with finitely many…

Category Theory · Mathematics 2015-03-06 Victor Ostrik

For any minor-closed class of matroids over a fixed finite field, we state an exact structural characterization for the sufficiently connected matroids in the class. We also state a number of conjectures that might be approachable using the…

Combinatorics · Mathematics 2015-01-06 Jim Geelen , Bert Gerards , Geoff Whittle

We define what is meant by a strict total order in a category having subobjects, products and fibre products. This allows us to define the notions of an ordered bundle X and an ordered G-set; when G=\pi_1(X) we relate these structures to…

Algebraic Topology · Mathematics 2012-08-30 Mathieu Anel , Adam Clay

We obtain the higher spin tractor equations of motion conjectured by Gover et al. from a BRST approach and use those methods to prove that they describe massive, partially massless and massless higher spins in conformally flat backgrounds.…

High Energy Physics - Theory · Physics 2015-05-28 Maxim Grigoriev , Andrew Waldron

A fundamental theorem of matroid theory establishes that a transversal matroid is representable over fields of any characteristic. It was proved in 1970 by Piff and Welsh: their proof is elegant and concise and, moveover, constructive.…

Combinatorics · Mathematics 2017-07-24 Carrie Rutherford , Robin Whitty

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

Arboreal categories were introduced as an axiomatic framework for game comonads, which provide a comonadic view on many model-comparison games in logic. We demonstrate the inadequacy of the axiom stating that paths are connected. We then…

Logic in Computer Science · Computer Science 2026-03-24 Tomáš Jakl , Luca Reggio

The concept of matchings originated in group theory to address a linear algebra problem related to canonical forms for symmetric tensors. In an abelian group $(G,+)$, a matching is a bijection $f: A \to B$ between two finite subsets $A$ and…

Combinatorics · Mathematics 2025-08-08 Mohsen Aliabadi , Yujia Wu , Sophia Yermolenko

We introduce the notions of proto-complete, complete, complete* and strong-complete objects in pointed categories. We show under mild conditions on a pointed exact protomodular category that every proto-complete (respectively complete)…

Category Theory · Mathematics 2021-02-22 James Richard Andrew Gray

Many combinatorial properties of a point set in the plane are determined by the set of possible partitions of the point set by a line. Their essential combinatorial properties are well captured by the axioms of oriented matroids. In fact,…

Combinatorics · Mathematics 2021-11-08 Hiroyuki Miyata

Given a scheme over a complete discrete valuation ring of mixed characteristic with perfect residue field, the Greenberg transform produces a new scheme over the residue field thicker than the special fiber. In this paper, we will…

Number Theory · Mathematics 2024-08-29 Alessandra Bertapelle , Takashi Suzuki