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Related papers: Limits of functions on groups

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We consider limits over categories of extensions and show how certain well-known functors on the category of groups turn out as such limits. We also discuss higher (or derived) limits over categories of extensions.

Category Theory · Mathematics 2009-05-21 Roman Mikhailov , Inder Bir S. Passi

For compact sets $K\subset \mathbb C^{d}$, we introduce a subalgebra $A_{D}(K)$ of $A(K)$, which allows us to obtain Mergelyan type theorems for products of planar compact sets as well as for graphs of functions.

Complex Variables · Mathematics 2019-01-08 Javier Falcó , Paul M. Gauthier , Myrto Manolaki , Vassili Nestoridis

In this paper, we define locally matchable subsets of a group which is extracted from the concept of matchings in groups and used as a tool to give alternative proofs for existing results in matching theory. We also give the linear analogue…

Group Theory · Mathematics 2019-10-28 Mohsen Aliabadia , Mano Vikash Janardhanan

We prove that the isomorphism problem for group algebras reduces to group algebras over finite extensions of the prime field. In particular, the modular isomorphism problem reduces to finite modular group algebras.

Representation Theory · Mathematics 2023-07-11 Diego García-Lucas , Ángel del Río

We bound the size of $d$-dimensional cubulations of finitely presented groups. We apply this bound to obtain acylindrical accessibility for actions on CAT(0) cube complexes and bounds on curves on surfaces.

Group Theory · Mathematics 2017-11-15 Benjamin Beeker , Nir Lazarovich

We study group extensions of Finite Abelian Groups using matrices. We also prove a Theorem for equivalence of extensions using matrices.

Group Theory · Mathematics 2018-02-16 Guhan Venkat

In this work, we introduce new approximation operators for univariate set-valued functions with general compact images. We adapt linear approximation methods for real-valued functions by replacing linear combinations of numbers with new…

Classical Analysis and ODEs · Mathematics 2007-05-23 Nira Dyn , Elza Farkhi , Alona Mokhov

We propose a general method for optimization with semi-infinite constraints that involve a linear combination of functions, focusing on the case of the exponential function. Each function is lower and upper bounded on sub-intervals by…

Optimization and Control · Mathematics 2014-01-13 Bogdan Dumitrescu , Bogdan C. Sicleru , Florin Avram

We propose a variable metric framework for minimizing the sum of a self-concordant function and a possibly non-smooth convex function, endowed with an easily computable proximal operator. We theoretically establish the convergence of our…

Machine Learning · Statistics 2014-04-15 Quoc Tran-Dinh , Anastasios Kyrillidis , Volkan Cevher

We give a topological framework for the study of Sela's limit groups: limit groups are limits of free groups in a compact space of marked groups. Many results get a natural interpretation in this setting. The class of limit groups is known…

Group Theory · Mathematics 2007-05-23 Christophe Champetier , Vincent Guirardel

We prove that every nonnegative continuous real-valued function on a given compact metric space is the uniform limit of some increasing sequence of nonnegative simple functions being linear combinations of indicators of open sets; here the…

General Mathematics · Mathematics 2020-10-21 Yu-Lin Chou

We study topological and geometric functionals of $l_\infty$-random geometric graphs on the high-dimensional torus in a sparse regime, where the expected number of neighbors decays exponentially in the dimension. More precisely, we…

Probability · Mathematics 2025-01-08 Gilles Bonnet , Christian Hirsch , Daniel Rosen , Daniel Willhalm

In this paper we describe a triple correspondence between graph limits, information theory and group theory. We put forward a new graph limit concept called log-convergence that is closely connected to dense graph limits but its main…

Combinatorics · Mathematics 2015-04-06 Balazs Szegedy

Symmetries occur naturally in CSP or SAT problems and are not very difficult to discover, but using them to prune the search space tends to be very challenging. Indeed, this usually requires finding specific elements in a group of…

Artificial Intelligence · Computer Science 2011-07-25 Thierry Boy de la Tour , Mnacho Echenim

We extend the work of Narasimhan and Bilmes [30] for minimizing set functions representable as a difference between submodular functions. Similar to [30], our new algorithms are guaranteed to monotonically reduce the objective function at…

Data Structures and Algorithms · Computer Science 2013-08-27 Rishabh Iyer , Jeff Bilmes

In this paper, we give the explicit bounds for the data of objects involved in some basic theorems of Singularity theory: the Inverse, Implicit and Rank Theorems for Lipschitz mappings, Splitting Lemma and Morse Lemma, the density and…

Numerical Analysis · Mathematics 2012-08-28 Ta Le Loi , Phan Phien

We consider mappings, which are structure consisting of a single function (and possibly some number of unary relations) and address the problem of approximating a continuous mapping by a finite mapping. This problem is the inverse problem…

Combinatorics · Mathematics 2018-05-15 Jaroslav Nesetril , Patrice Ossona de Mendez

We generalize the box and observable distances to those between metric measure spaces with group actions, and prove some fundamental properties. As an application, we obtain an example of a sequence of lens spaces with unbounded dimension…

Metric Geometry · Mathematics 2021-04-21 Hiroki Nakajima , Takashi Shioya

The aim of this paper is to prove the existence of inductive and inverse limits of direct and inverse systems in a certain category of compact metric spaces as well as of compact metric groups. Some applications are presented.

General Topology · Mathematics 2022-11-28 Kamil Urbaś

The concept of a C-approximable group, for a class of finite groups C, is a common generalization of the concepts of a sofic, weakly sofic, and linear sofic group. Glebsky raised the question whether all groups are approximable by finite…

Group Theory · Mathematics 2017-05-25 Nikolay Nikolov , Jakob Schneider , Andreas Thom