Matroid theory

Base-orderable matroid

In mathematics, a base-orderable matroid is a matroid that has the following additional property, related to the bases of the matroid. For any two bases and there exists a feasible exchange bijection, defined as a bijection from to , such that for every , both and are bases. The property was introduced by Brualdi and Scrimger. A strongly-base-orderable matroid has the following stronger property: For any two bases and , there is a strong feasible exchange bijection, defined as a bijection from to , such that for every , both and are bases. (Wikipedia).

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Orders on Sets: Part 1 - Partial Orders

This was recorded as supplemental material for Math 115AH at UCLA in the spring quarter of 2020. In this video, I discuss the concept and definition of a partial order.

From playlist Orders on Sets

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Set Theory (Part 3): Ordered Pairs and Cartesian Products

Please feel free to leave comments/questions on the video and practice problems below! In this video, I cover the Kuratowski definition of ordered pairs in terms of sets. This will allow us to speak of relations and functions in terms of sets as the basic mathematical objects and will ser

From playlist Set Theory by Mathoma

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Order of Elements in a Group | Abstract Algebra

We introduce the order of group elements in this Abstract Algebra lessons. We'll see the definition of the order of an element in a group, several examples of finding the order of an element in a group, and we will introduce two basic but important results concerning distinct powers of ele

From playlist Abstract Algebra

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Set Theory (Part 2): ZFC Axioms

Please feel free to leave comments/questions on the video and practice problems below! In this video, I introduce some common axioms in set theory using the Zermelo-Fraenkel w/ choice (ZFC) system. Five out of nine ZFC axioms are covered and the remaining four will be introduced in their

From playlist Set Theory by Mathoma

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Joseph Bonin: Delta-matroids as subsystems of sequences of Higgs lifts

Abstract: Delta-matroids generalize matroids. In a delta-matroid, the counterparts of bases, which are called feasible sets, can have different sizes, but they satisfy a similar exchange property in which symmetric differences replace set differences. One way to get a delta-matroid is to t

From playlist Combinatorics

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Anna De Mier: Approximating clutters with matroids

Abstract: There are several clutters (antichains of sets) that can be associated with a matroid, as the clutter of circuits, the clutter of bases or the clutter of hyperplanes. We study the following question: given an arbitrary clutter Λ, which are the matroidal clutters that are closest

From playlist Combinatorics

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Dihedral Group (Abstract Algebra)

The Dihedral Group is a classic finite group from abstract algebra. It is a non abelian groups (non commutative), and it is the group of symmetries of a regular polygon. This group is easy to work with computationally, and provides a great example of one connection between groups and geo

From playlist Abstract Algebra

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Gyula Pap: Linear matroid matching in the oracle model

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From playlist HIM Lectures 2015

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Field Definition (expanded) - Abstract Algebra

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From playlist Abstract Algebra

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Nonlinear algebra, Lecture 13: "Polytopes and Matroids ", by Mateusz Michalek

This is the thirteenth lecture in the IMPRS Ringvorlesung, the advanced graduate course at the Max Planck Institute for Mathematics in the Sciences.

From playlist IMPRS Ringvorlesung - Introduction to Nonlinear Algebra

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Product groups

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From playlist Abstract algebra

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The realm of natural numbers | Data structures in Mathematics Math Foundations 155

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From playlist Math Foundations

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Victor Chepoi: Simple connectivity, local to global, and matroids

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From playlist HIM Lectures 2015

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Connecting tropical intersection theory with polytope algebra in types A and B by Alex Fink

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From playlist Combinatorial Algebraic Geometry: Tropical and Real (HYBRID)

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Yusuke Kobayashi: A weighted linear matroid parity algorithm

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From playlist Follow-Up-Workshop "Combinatorial Optimization"

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Sahil Singla: Online Matroid Intersection Beating Half for Random Arrival

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From playlist HIM Lectures 2015

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Centralizer of a set in a group

A centralizer consider a subset of the set that constitutes a group and included all the elements in the group that commute with the elements in the subset. That's a mouthful, but in reality, it is actually an easy concept. In this video I also prove that the centralizer of a set in a gr

From playlist Abstract algebra

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Lauren Williams - Combinatorics of the amplituhedron

The amplituhedron is the image of the positive Grassmannian under a map in- duced by a totally positive matrix. It was introduced by Arkani-Hamed and Trnka to compute scattering amplitudes in N=4 super Yang Mills. I’ll give a gentle introduction to the amplituhedron, surveying its connecti

From playlist Combinatorics and Arithmetic for Physics: Special Days 2022

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[Discrete Mathematics] Indexed Sets and Well Ordering Principle

Today we discuss indexed sets and the well ordering principle. Visit my website: http://bit.ly/1zBPlvm Subscribe on YouTube: http://bit.ly/1vWiRxW *--Playlists--* Discrete Mathematics 1: https://www.youtube.com/playlist?list=PLDDGPdw7e6Ag1EIznZ-m-qXu4XX3A0cIz Discrete Mathematics 2: http

From playlist Discrete Math 1

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Galois theory: Transcendental extensions

This lecture is part of an online graduate course on Galois theory. We describe transcendental extension of fields and transcendence bases. As applications we classify algebraically closed fields and show hw to define the dimension of an algebraic variety.

From playlist Galois theory

Related pages

Graphic matroid | Bijection | Clique (graph theory) | Basis of a matroid | Partition matroid | Matroid