English
Related papers

Related papers: Weakly convex sets and modulus of nonconvexity

200 papers

In this paper, we introduce the notions uniformly p-convergent sets and weakly p-sequentially continuous differentiable mappings. Then we obtain a sufficient condition for those Banach spaces which either contain no copy of $\ell_1$ or have…

Functional Analysis · Mathematics 2020-01-01 Morteza Alikhani

In this paper we study different aspects of the representation of weak*-compact convex sets of the bidual $X^{**}$ of a separable Banach space $X$ via a nested sequence of closed convex bounded sets of $X$.

Functional Analysis · Mathematics 2014-06-27 Jesús M. F. Castillo , Manuel González , Pier Luigi Papini

We introduce a class of stochastic algorithms for minimizing weakly convex functions over proximally smooth sets. As their main building blocks, the algorithms use simplified models of the objective function and the constraint set, along…

Optimization and Control · Mathematics 2025-01-22 Damek Davis , Dmitriy Drusvyatskiy , Zhan Shi

Weak sharp minimality is a notion emerged in optimization, whose utility is largeley recognized in the convergence analysis of algorithms for solving extremum problems as well as in the study of the perturbation behaviour of such problems.…

Optimization and Control · Mathematics 2013-01-23 Amos Uderzo

In this note we propose a definition of weak solution for an abstract Cauchy problem in a Hilbert space, and we discuss existence and uniqueness results.

Analysis of PDEs · Mathematics 2024-06-05 Vittorino Pata , Justin T. Webster

Properties of two classes of generally convex sets in the n-dimentional real Euclidean space, called m-semiconvex and weakly m-semiconvex, 1<=m<n, are investigated in the present work. In particular, it is established that an open set with…

Geometric Topology · Mathematics 2017-11-15 Tetiana Osipchuk

Evenly convex sets in a topological vector space are defined as the intersection of a family of open half spaces. We introduce a generalization of this concept in the conditional framework and provide a generalized version of the bipolar…

Probability · Mathematics 2012-09-06 Marco Frittelli , Marco Maggis

In this article, we investigate the existence of joins in the weak order of an infinite Coxeter group W. We give a geometric characterization of the existence of a join for a subset X in W in terms of the inversion sets of its elements and…

Group Theory · Mathematics 2016-05-10 Christophe Hohlweg , Jean-Philippe Labbé

We provide sufficient conditions for a Banach space Y to be weakly sequentially complete. These conditions are expressed in terms of the existence of directional derivatives for cone convex mappings with values in Y .

Optimization and Control · Mathematics 2016-02-20 E. M. Bednarczuk , K. Leśniewski

The present work considers the properties of generally convex sets in the $n$-dimensional real Euclidean space $\mathbb{R}^n$, $n>1$, known as weakly $m$-convex, $m=1,2,\ldots,n-1$. An open set of $\mathbb{R}^n$ is called weakly $m$-convex…

Metric Geometry · Mathematics 2021-11-03 Tetiana Osipchuk

Nearly convex sets play important roles in convex analysis, optimization and theory of monotone operators. We give a systematic study of nearly convex sets, and construct examples of subdifferentials of lower semicontinuous convex functions…

Optimization and Control · Mathematics 2015-07-28 Sarah M. Moffat , Walaa M. Moursi , Xianfu Wang

In this paper, we study VC-minimal theories and explore related concepts. We first define the notion of convex orderablility and show that this lies strictly between VC-minimality and dp-minimality. Next, we define the notion of weak…

Logic · Mathematics 2011-10-20 Vincent Guingona , Michael C. Laskowski

We show that every Banach space in which weakly compact sets are super weakly compact in automatically weakly sequentially complete answering a question by Silber (2024). In the proof we show how to build a weakly compact set which is not…

Functional Analysis · Mathematics 2025-01-29 Zdeněk Silber

The class of convex sets that admit approximations as Minkowski sum of a compact convex set and a closed convex cone in the Hausdorff distance is introduced. These sets are called approximately Motzkin-decomposable and generalize the notion…

Optimization and Control · Mathematics 2024-01-25 Daniel Dörfler , Andreas Löhne

It is proved that every normalized weakly null \sq\ has a sub\sq\ which is convexly unconditional. Further, an Hierarchy of summability methods is introduced and with this we give a complete classification of the complexity of weakly null…

Functional Analysis · Mathematics 2016-09-06 Spiros A. Argyros , S. Merkourakis , A. Tsarpalias

We propose a new class of hypertopologies, called here weak$^{\ast }$ hypertopologies, on the dual space $\mathcal{X}^{\ast }$ of a real or complex topological vector space $\mathcal{X}$. The most well-studied and well-known hypertopology…

Functional Analysis · Mathematics 2021-03-16 J. -B. Bru , W. de Siqueira Pedra

This is the first in a projected series of three papers in which we construct the second flip in the log minimal model program for $\bar{M}_g$. We introduce the notion of a weakly proper algebraic stack, which may be considered as an…

Algebraic Geometry · Mathematics 2015-03-17 Jarod Alper , David Ishii Smyth , Frederick van der Wyck

The aim of this paper is to describe the classes of strongly flat and weakly cotorsion modules with respect to a multiplicative subset or a finite collection of multiplicative subsets in a commutative ring. The strongly flat modules are…

Commutative Algebra · Mathematics 2019-04-08 Leonid Positselski , Alexander Slavik

In this paper we show that if $(y_n)$ is a seminormalized sequence in a Banach space which does not have any weakly convergent subsequence, then it contains a wide-$(s)$ subsequence $(x_n)$ which admits an equivalent convex basic sequence.…

Functional Analysis · Mathematics 2018-03-26 C. S. Barroso , V. Ferreira

This paper introduces a new subtraction operation for convex sets, which defines their difference as a collection of inclusion-minimal convex sets with appropriate definitions of linear operations on them. With these operations the set of…

Optimization and Control · Mathematics 2018-06-18 Evgeni Nurminski , Stan Uryasev