English
Related papers

Related papers: Matrix Convex Sets Without Absolute Extreme Points

200 papers

We present a framework to obtain valid inequalities for a reverse convex set: the set of points in a polyhedron that lie outside a given open convex set. Reverse convex sets arise in many models, including bilevel optimization and…

Optimization and Control · Mathematics 2020-12-02 Eli Towle , James Luedtke

Let X be a compact convex set and let ext X stand for the set of extreme points of X. We show that an affine function with the point of continuity property on X satisfies the minimum principle. As a corollary we obtain a generalization of a…

Functional Analysis · Mathematics 2018-01-25 Petr Dostál , Jiří Spurný

Several results concerning pairs of polynomially convex sets whose union is not even rationally convex are given. It is shown that there is no restriction on how two spaces can be embedded in some $\C^N$ so as to be polynomially convex but…

Complex Variables · Mathematics 2021-08-23 Alexander J. Izzo

We study the algebraic boundary of a convex semi-algebraic set via duality in convex and algebraic geometry. We generalize the correspondence of facets of a polytope to the vertices of the dual polytope to general semi-algebraic convex…

Algebraic Geometry · Mathematics 2014-11-04 Rainer Sinn

The $K$-hull of a compact set $A\subset\mathbb{R}^d$, where $K\subset \mathbb{R}^d$ is a fixed compact convex body, is the intersection of all translates of $K$ that contain $A$. A set is called $K$-strongly convex if it coincides with its…

Metric Geometry · Mathematics 2021-10-06 Alexander Marynych , Ilya Molchanov

This paper presents a novel convex optimization-based method for finding the globally optimal solutions of a class of mixed-integer non-convex optimal control problems. We consider problems with non-convex constraints that restrict the…

Optimization and Control · Mathematics 2019-11-21 Danylo Malyuta , Behcet Acikmese

We study the problems of testing and learning high-dimensional discrete convex sets. The simplest high-dimensional discrete domain where convexity is a non-trivial property is the ternary hypercube, $\{-1,0,1\}^n$. The goal of this work is…

Data Structures and Algorithms · Computer Science 2023-11-21 Hadley Black , Eric Blais , Nathaniel Harms

A matrix convex set is a set of the form $\mathcal{S} = \cup_{n\geq 1}\mathcal{S}_n$ (where each $\mathcal{S}_n$ is a set of $d$-tuples of $n \times n$ matrices) that is invariant under UCP maps from $M_n$ to $M_k$ and under formation of…

Operator Algebras · Mathematics 2025-04-15 Kenneth R. Davidson , Adam Dor-On , Orr Shalit , Baruch Solel

In this paper we theoretically show that interior-point methods based on self-concordant barriers possess favorable global complexity beyond their standard application area of convex optimization. To do that we propose first- and…

Optimization and Control · Mathematics 2024-04-30 Pavel Dvurechensky , Mathias Staudigl

We consider the problem of projecting a convex set onto a subspace, or equivalently formulated, the problem of computing a set obtained by applying a linear mapping to a convex feasible set. This includes the problem of approximating convex…

Optimization and Control · Mathematics 2024-12-11 Gabriela Kováčová , Birgit Rudloff

Low-rank matrix completion consists of computing a matrix of minimal complexity that recovers a given set of observations as accurately as possible. Unfortunately, existing methods for matrix completion are heuristics that, while highly…

Machine Learning · Computer Science 2026-03-12 Dimitris Bertsimas , Ryan Cory-Wright , Sean Lo , Jean Pauphilet

Our work explores fusions, the multidimensional counterparts of mean-preserving contractions and their extreme and exposed points. We reveal an elegant geometric/combinatorial structure for these objects. Of particular note is the…

Theoretical Economics · Economics 2025-02-11 Andreas Kleiner , Benny Moldovanu , Philipp Strack , Mark Whitmeyer

We present a self-contained analysis of a particular family of metrics over the set of non-negative integers. We show that these metrics, which are defined through a nested sequence of optimal transport problems, provide tight estimates for…

Optimization and Control · Mathematics 2022-04-21 Mario Bravo , Thierry Champion , Roberto Cominetti

We study the integrality gap of convex mixed-integer programs, that is, the difference between the optimal value of such a problem and the optimal value of its continuous relaxation. We study classes of convex sets whose associated…

Optimization and Control · Mathematics 2026-04-20 Burak Kocuk , Diego Moran Ramirez

Let \Gamma be the convex set consisting of all marginal tracial states on the tensor product B \otimes B of the algebra B of nxn matrices over the complex numbers. We find necessary and sufficient conditions for such a state to be extremal…

Operator Algebras · Mathematics 2007-05-23 Geoffrey L. Price , Shoichuro Sakai

Convex clustering is a well-regarded clustering method, resembling the similar centroid-based approach of Lloyd's $k$-means, without requiring a predefined cluster count. It starts with each data point as its centroid and iteratively merges…

Machine Learning · Statistics 2026-05-15 Shubhayan Pan , Kushal Bose , Debolina Paul , Saptarshi Chakraborty , Swagatam Das

In this paper, the proximal point algorithm for quasi-convex minimization problem in nonpositive curvature metric spaces is studied. We prove $\Delta$-convergence of the generated sequence to a critical point (which is defined in the text)…

Functional Analysis · Mathematics 2016-11-08 Hadi Khatibzadeh , Vahid Mohebbi

A convex geometry is a closure system satisfying the anti-exchange property. This paper, following the work of K. Adaricheva and M. Bolat (2016) and the Polymath REU 2020 team, continues to investigate representations of convex geometries…

Combinatorics · Mathematics 2022-06-14 Kira Adaricheva , Evan Daisy , Ayush Garg , Zachary King , Grace Ma , Michelle Olson , Cat Raanes , James Thompson

Motivated by the well-known cases of the real Hilbert ball and complete R-trees, being both particular cases of CAT(-1) spaces, we give an affirmative answer to the question of whether the geodesically boundedness property is a necessary…

Metric Geometry · Mathematics 2014-08-01 Bozena Piatek

The goal of this paper is to establish certain inequalities between the numbers of convex polytopes in the d-dimensional space "containing" and "avoiding" zero provided that their vertex sets are subsets of a given finite set of points in…

Combinatorics · Mathematics 2013-12-24 Alexander Kelmans , Anatoliy Rubinov