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Related papers: Fra\"iss\'e limits of metric structures

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In this note, we survey two instances in the representation theory of finite-dimensional algebras where the quantity of a type of structures is intimately related to the size of those same structures. More explicitly, we review the fact…

Representation Theory · Mathematics 2020-01-15 Jorge Vitória

Motivated by the work of Lov\'asz and Szegedy on the convergence and limits of dense graph sequences, we investigate the convergence and limits of finite trees with respect to sampling in normalized distance. Based on separable real trees,…

Combinatorics · Mathematics 2021-10-19 Gábor Elek , Gábor Tardos

Federer's characterization of sets of finite perimeter states (in Euclidean spaces) that a set is of finite perimeter if and only if the measure-theoretic boundary of the set has finite Hausdorff measure of codimension one. In complete…

Metric Geometry · Mathematics 2018-05-01 Panu Lahti

We study an infinite family of one-parameter deformations, so-called $\alpha$-continued fractions, of interval maps associated to distinct triangle Fuchsian groups. In general for such one-parameter deformations, the function giving the…

Dynamical Systems · Mathematics 2017-01-18 Kariane Calta , Cor Kraaikamp , Thomas A. Schmidt

Classical Ramsey theory has successfully extended to relational structures, yielding a wealth of results that have profoundly influenced other areas of mathematics. Interestingly, the same development has not occurred in the case of dual…

Combinatorics · Mathematics 2025-07-02 Aleksa Džuklevski , Dragan Mašulović

Finite Unified Theories (FUTs) are N=1 supersymmetric Grand Unified Theories that can be made all-loop finite. The requirement of all-loop finiteness leads to a severe reduction of the free parameters of the theory and, in turn, to a large…

High Energy Physics - Phenomenology · Physics 2009-01-06 S. Heinemeyer , M. Mondragon , G. Zoupanos

We determine when an arithmetic subgroup of a reductive group defined over a global function field is of type FP_\infty by comparing its large-scale geometry to the large-scale geometry of lattices in real semisimple Lie groups.

Group Theory · Mathematics 2007-05-23 Kai-Uwe Bux , Kevin Wortman

We prove that the automorphism group of a Fra\"iss\'e structure M equipped with a notion of stationary independence is universal for the class of automorphism groups of substructures of M. Furthermore, we show that this applies to certain…

Logic · Mathematics 2015-01-20 Isabel Müller

Let M be the generic poset, defined as the Fra\"iss\'e limit of the class of finite posets. We show that every countably infinite poset A can be embedded with coinfinite image into M so that each automorphism of the image of A extends…

Logic · Mathematics 2025-08-19 Aleksandra Kwiatkowska , Rob Sullivan , Jeroen Winkel

A characterization of finite homogeneous ultrametric spaces and finite ultrametric spaces generated by unrooted labeled trees is found in terms of representing trees. A characterization of finite ultrametric spaces having perfect strictly…

General Topology · Mathematics 2024-12-24 Evgeniy A. Petrov

We prove that, consistently with ZFC, no ultraproduct of countably infinite (or separable metric, non-compact) structures is isomorphic to a reduced product of countable (or separable metric) structures associated to the Fr\'echet filter.…

Logic · Mathematics 2022-07-18 Ilijas Farah , Saharon Shelah

If F is a finitely generated free group and \phi is an automorphism of F then the mapping torus of \phi admits a quadratic isoperimetric inequality. This is the third and final paper in a series proving this theorem. The first two were…

Group Theory · Mathematics 2007-05-23 M. R. Bridson , D. Groves

We consider metric ultraproducts of finite groups with respect to some classes of length functions. All sofic groups embed into these ultraproducts. We study embeddings of normed groups. We also show that in some natural situations such an…

Group Theory · Mathematics 2014-01-07 A. Ivanov

Two finitely generated groups have the same set of finite quotients if and only if their profinite completions are isomorphic. Consider the map which sends (the isomorphism class of) an S-arithmetic group to (the isomorphism class of) its…

Group Theory · Mathematics 2011-10-25 Menny Aka

In topological data science, categories with a flow have become ubiquitous, including as special cases examples like persistence modules and sheaves. With the flow comes an interleaving distance, which has proven useful for applications. We…

Category Theory · Mathematics 2019-01-16 Joshua Cruz

Under no additional assumptions, in this paper we construct a Ramsey expansion for every category of finite objects with finite small Ramsey degrees. Our construction is based on the relationship between small Ramsey degrees, weak…

Logic · Mathematics 2022-08-25 Dragan Mašulović , Andy Zucker

We introduce an effective field theory (EFT) for conformal impurity by considering a pair of transversely displaced impurities and integrating out modes with mass inversely proportional to the separation distance. This EFT captures the…

High Energy Physics - Theory · Physics 2024-06-11 Oleksandr Diatlyk , Himanshu Khanchandani , Fedor K. Popov , Yifan Wang

Suppose $\mathscr{L}^-\subseteq \mathscr{L}$ are languages where $\mathscr{L} \setminus\mathscr{L}^-$ is relational. Additionally, let $\mathbf{K}$ be a strong $\textrm{Fra\"iss\'e}$ class in $\mathscr{L}$. We consider the partial ordering,…

Logic · Mathematics 2024-06-06 Nathanael Ackerman , Mohammad Golshani , Mostafa Mirabi

We generalize the notion of relational precompact expansions of Fra\"iss\'e classes via functorial means, inspired by the technique outlined by Laflamme, Nguyen Van Th\'e and Sauer in their paper Partition properties of the dense local…

Combinatorics · Mathematics 2020-02-28 Keegan Dasilva Barbosa

We describe a theory of finite sets, and investigate the analogue of Dedekind's theory of natural number systems (simply infinite systems) in this theory. Unlike the infinitary case, in our theory, natural number systems come in differing…

Logic · Mathematics 2008-08-08 J. P. Mayberry , Richard Pettigrew