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Related papers: Some definable types that cannot be amalgamated

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The goal of this article is to study results and examples concerning finitely presented covers of finitely generated amenable groups. We collect examples of groups $G$ with the following properties: (i) $G$ is finitely generated, (ii) $G$…

Group Theory · Mathematics 2013-05-06 Mustafa Gokhan Benli , Rostislav Grigorchuk , Pierre De La Harpe

A typoid is a type equipped with an equivalence relation, such that the terms of equivalence between the terms of the type satisfy certain conditions, with respect to a given equivalence relation between them, that generalise the properties…

Category Theory · Mathematics 2022-05-16 Iosif Petrakis

We establish the choice property, a weak analogue of definable choice, for certain tame expansions of o-minimal structures. Most noteworthily, dense pairs of real closed fields have this property.

Logic · Mathematics 2017-08-15 Pantelis E. Eleftheriou , Ayhan Günaydın , Philipp Hieronymi

We give a new proof of the simultaneous embedded local uniformization Theorem in zero characteristic for essentially of finite type rings and for quasi excellent rings. The results are a consequence of the simultaneaous monomialization…

Commutative Algebra · Mathematics 2020-10-19 Julie Decaup

We show that there do not exist semistable varietes defined over the rationals with good reduction outside one prime p if p = 2, 3, 5 or 7.

Number Theory · Mathematics 2007-05-23 Armand Brumer , Kenneth Kramer

Let G be a semisimple group over an algebraically closed field of characteristic p>0. We give a (partly conjectural) simple, closed formula for the character of many indecomposable tilting rational G-modules, assuming that p is large.

Representation Theory · Mathematics 2015-02-18 George Lusztig , Geordie Williamson

Arbitrarily many pairwise inequivalent modular categories can share the same modular data. We exhibit a family of examples that are module categories over twisted Drinfeld doubles of finite groups, and thus in particular integral modular…

Quantum Algebra · Mathematics 2021-06-09 Michaël Mignard , Peter Schauenburg

Our main result (Theorem A) shows the incompleteness of any consistent sequential theory T formulated in a finite language such that T is axiomatized by a collection of sentences of bounded quantifier-alternation-depth. Our proof employs an…

Logic · Mathematics 2024-02-19 Ali Enayat , Albert Visser

We investigate the existence of "generic derivations" in exponential fields. We show that exponential fields without additional compatibility conditions between derivation and exponentiation cannot support a generic derivation.

Logic · Mathematics 2024-07-23 Fornasiero Antongiulio , Giuseppina Terzo

In this short note we present several infinite dimensional theorems which generalize corresponding facts from the finite dimensional differential inclusions theory.

Functional Analysis · Mathematics 2021-07-19 Evgenii Borisenko , Oleg Zubelevich

Except for a limited number of cases, a complete classification of the Diophantine sets of polynomial rings and fields of rational functions seems out of reach at present. We contribute to this problem by proving that several natural sets…

Number Theory · Mathematics 2022-10-20 Natalia Garcia-Fritz , Hector Pasten , Thanases Pheidas

We show that neither the class of C*-algebras with Kirchberg's QWEP property nor the class of W*-probability spaces with the QWEP property are effectively axiomatizable (in the appropriate languages). The latter result follows from a more…

Operator Algebras · Mathematics 2023-08-29 Jananan Arulseelan , Isaac Goldbring , Bradd Hart

Free independence is an important tool for studying the structure of operator algebras. It is natural to ask from the model-theoretic standpoint whether free independence is captured well in first-order model theory via the notion of a…

Operator Algebras · Mathematics 2026-02-25 William Boulanger , Jakub Curda , Emma Harvey , Yizhi Li , Jennifer Pi

This paper provides an extensive study of the homotopy theory of types of algebras with units, like unital associative algebras or unital commutative algebras for instance. To this purpose, we endow the Koszul dual category of curved…

Algebraic Topology · Mathematics 2019-05-29 Brice Le Grignou

We study mixed identities for oligomorphic automorphism groups of countable relational structures. Our main result gives sufficient conditions for such a group to not admit a mixed identity without particular constants. We study numerous…

Group Theory · Mathematics 2025-08-20 Manuel Bodirsky , Jakob Schneider , Andreas Thom

Let $T$ be a (first order complete) dependent theory, ${\mathfrak{C}}$ a $\bar\kappa$-saturated model of $T$ and $G$ a definable subgroup which is abelian. Among subgroups of bounded index which are the union of $<\bar\kappa$ type definable…

Logic · Mathematics 2021-09-15 Saharon Shelah

The intended model of the homotopy type theories used in Univalent Foundations is the infinity-category of homotopy types, also known as infinity-groupoids. The problem of higher structures is that of constructing the homotopy types needed…

Logic · Mathematics 2018-07-09 Ulrik Buchholtz

The paper proposes a logical model of combinatorial problems, also it gives an example of a problem of the class NP that can not be solved in polynomial time on the dimension of the problem.

Computational Complexity · Computer Science 2016-03-02 Anatoly D. Plotnikov

This paper presents a type theory in which it is possible to directly manipulate $n$-dimensional cubes (points, lines, squares, cubes, etc.) based on an interpretation of dependent type theory in a cubical set model. This enables new ways…

Logic in Computer Science · Computer Science 2016-11-14 Cyril Cohen , Thierry Coquand , Simon Huber , Anders Mörtberg

We construct examples of principal groupoids that have weak containment but are not amenable, thus answering questions by Claire Anantharaman-Delaroche and Rufus Willett.

Operator Algebras · Mathematics 2018-04-25 Vadim Alekseev , Martin Finn-Sell