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Related papers: Examples of weak amalgamation classes

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Usually when we have polyadic-like algebras, meaning that we have infinitary substitutions (that is substitutions moving infinitely many points) in the similarity type, then we get the superamalgamation property especially if this class of…

Logic · Mathematics 2013-04-05 Tarek Sayed Ahmed

Various characterizations of finite convex geometries are well known. This note provides similar characterizations for possibly infinite convex geometries whose lattice of closed sets is strongly coatomic and lower continuous. Some classes…

Combinatorics · Mathematics 2017-01-27 Kira Adaricheva , J. B. Nation

The two model-theoretic concepts of weak saturation and weak amalgamation property are studied in the context of accessible categories. We relate these two concepts providing sufficient conditions for existence and uniqueness of weakly…

Category Theory · Mathematics 2025-08-06 Ivan Di Liberti

We prove a version of Bass' finitistic dimension conjecture for path algebras over arbitrary directed graphs. It is known that the path algebra of a finite directed graph is hereditary, hence it has finite finitistic dimension, when the…

K-Theory and Homology · Mathematics 2013-02-20 Muge Kanuni , Atabey Kaygun

We prove that the joint embedding property is undecidable for hereditary graph classes, via a reduction from the tiling problem. The proof is then adapted to show the undecidability of the joint homomorphism property as well.

Logic · Mathematics 2023-06-22 Samuel Braunfeld

We consider the group property of being icc. We give several examples of icc groups and study its stability under usual algebraic constructions.

Group Theory · Mathematics 2007-05-23 Jean-Philippe Preaux

We provide a self-contained introduction to the classical theory of universal-homogeneous models (also known as generic structures, rich models, or Fra\"iss\'e limits). In the literature, most treatments restrict consideration to embeddings…

Logic · Mathematics 2010-09-10 Silvia Barbina , Domenico Zambella

Building upon previous works of Proudfoot and Ramos, and using the categorical framework of Sam and Snowden, we extend the weak categorical minor theorem from undirected graphs to quivers. As case of study, we investigate the consequences…

Algebraic Topology · Mathematics 2024-01-03 Luigi Caputi , Carlo Collari , Eric Ramos

In dealing with asymptotic approximation of possibly divergent nets of probability distributions, we are led to study uniform structures on the set of distributions. This paper identifies a class of such uniform structures that may be…

Probability · Mathematics 2010-11-23 Jan Pachl

We investigate the extent to which the weak equivalences in a model category can be equipped with algebraic structure. We prove, for instance, that there exists a monad T such that a morphism of topological spaces admits T-algebra structure…

Category Theory · Mathematics 2022-01-31 John Bourke

We present three examples of countable homogeneous structures (also called Fraisse limits) whose automorphism groups are not universal, namely, fail to contain isomorphic copies of all automorphism groups of their substructures. Our first…

Group Theory · Mathematics 2021-08-25 W. Kubis , S. Shelah

We characterize the equivalence and the weak equivalence of Cayley graphs for a finite group $\C{A}$. Using these characterizations, we find enumeration formulae of the equivalence classes and weak equivalence classes of Cayley graphs. As…

Combinatorics · Mathematics 2007-05-23 Dongseok Kim , Jin Hwan Kim , Jaeun Lee , Dianjun Wang

We show that the theories of partially ordered sets, lattices, semilattices, Boolean algebras, Heyting algebras with a further coarser partial order, or a linearization, or an auxiliary relation have the strong amalgamation property,…

Logic · Mathematics 2023-07-04 Paolo Lipparini

The law of a finite graph is a probability measure induced by the orbits of the graph under its automorphism group. Every law satisfies the intrinsic mass transport principle, which is also known as unimodularity. We discuss the convergence…

Combinatorics · Mathematics 2011-03-30 Igor Artemenko

We study the preservation of certain properties under products of classes of finite structures. In particular, we examine indivisibility, definable self-similarity, the amalgamation property, and the disjoint n-amalgamation property. We…

Logic · Mathematics 2023-09-14 Vince Guingona , Miriam Parnes , Lynn Scow

We present examples of foliations with infinite dimensional basic symplectic and com- plex cohomologies, along with a general sufficient condition for such phenomena. This puts re- strictions on possible generalizations of several…

Differential Geometry · Mathematics 2017-05-08 Andrzej Czarnecki , Paweł Raźny

A countable, bounded degree graph is almost finite if it has a tiling with isomorphic copies of finitely many F\o lner sets, and we call it strongly almost finite, if the tiling can be randomized so that the probability that a vertex is on…

Group Theory · Mathematics 2025-09-22 Gábor Elek , Ádám Timár

We define a notion of a weak canonical base for a partial type. This notion is weaker than the usual canonical base for an amalgamation base. We prove that certain family of partial types have a weak canonical base. This family clearly…

Logic · Mathematics 2013-11-14 Ziv Shami

We prove for residually finite groups the following long standing conjecture: the number of twisted conjugacy classes of an automorphism of a finitely generated group is equal (if it is finite) to the number of finite dimensional…

Group Theory · Mathematics 2012-05-01 Alexander Fel'shtyn , Evgenij Troitsky

We give a simple construction of new, complete, finite volume manifolds $M$ of bounded, nonpositive curvature. These manifolds have ends that look like a mixture of locally symmetric ends of different ranks and their fundamental groups are…

Geometric Topology · Mathematics 2021-03-17 Grigori Avramidi , T. Tam Nguyen Phan