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We consider the concept of a generalised manifold in the O(d,d) setting, i.e., in double geometry. The conjecture by Hohm and Zwiebach for the form of finite generalised diffeomorphisms is shown to hold. Transition functions on overlaps are…

High Energy Physics - Theory · Physics 2015-06-18 David S. Berman , Martin Cederwall , Malcolm J. Perry

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 survey foundational principles of Grothendieck's generalized spaces, including a critical glossary of the various, and often conflicting, terminological usages. Known results using generalized points support a fully pointwise notation…

Category Theory · Mathematics 2022-06-03 Steven Vickers

In this paper, an approach for generalizing the Gromov-Hausdorff metric is presented, which applies to metric spaces equipped with some additional structure. A special case is the Gromov-Hausdorff-Prokhorov metric between measured metric…

Metric Geometry · Mathematics 2023-11-30 Ali Khezeli

The class $\mathfrak C $ relative to countably compact topological spaces and the class $\mathfrak P$ relative to pseudocompact spaces introduced by Z. Frol\'ik are naturally generalized relative to every topological property. We provide a…

General Topology · Mathematics 2015-03-10 Paolo Lipparini

We develop a theory of generalized presentations of groups. We give generalized presentations of the symmetric group $\Sigma(X)$ for an arbitrary set $X$ and of the automorphism group of the free group of countable rank, $Aut(F_{\omega})$.

Group Theory · Mathematics 2011-07-08 Oleg Bogopolski , Wilhelm Singhof

We present a general definition of entropy in the setting of pre-ordered semigroups, extending the notion of topological entropy. From our definition, we obtain the basic properties exhibited by various entropy-like theories encountered in…

Dynamical Systems · Mathematics 2023-04-26 Mauricio Achigar

This paper proposes to compute the meanings associated to sentences with generic NPs corresponding to the most of generalized quantifier. We call these generics specimens and they resemble stereotypes or prototypes in lexical semantics. The…

Logic · Mathematics 2011-11-09 Christian Retoré

We exhibit a connection between geometric stability theory and the classification of unstable structures at the level of simplicity and the $\mathrm{NSOP}_{1}$-$\mathrm{SOP}_{3}$ gap. Particularly, we introduce generic expansions $T^{R}$ of…

Logic · Mathematics 2023-05-31 Scott Mutchnik

We determine the sets definable in expansions of the ordered real additive group by generalized Cantor sets. Given a natural number $r\geq 3$, we say a set $C$ is a generalized Cantor set in base $r$ if there is a non-empty…

Logic · Mathematics 2017-01-31 William Balderrama , Philipp Hieronymi

We study generalized splines from the perspective of the representation theory of the category of graphs with contractions. Our main theorem proves a kind of finite generation, which in turn implies the existence of a ``universal generating…

Combinatorics · Mathematics 2026-05-26 Jacob Matherne , Eric Ramos , Julianna Tymoczko

We introduce an abstract topos-theoretic framework for building Galois-type theories in a variety of different mathematical contexts; such theories are obtained from representations of certain atomic two-valued toposes as toposes of…

Category Theory · Mathematics 2013-01-03 Olivia Caramello

We study random composite structures considered up to symmetry that are sampled according to weights on the inner and outer structures. This model may be viewed as an unlabelled version of Gibbs partitions and encompasses multisets of…

Combinatorics · Mathematics 2020-04-01 Benedikt Stufler

We introduce the $\Sigma_1$-definable universal finite sequence and prove that it exhibits the universal extension property amongst the countable models of set theory under end-extension. That is, (i) the sequence is $\Sigma_1$-definable…

Logic · Mathematics 2020-11-11 Joel David Hamkins , Kameryn J. Williams

In type theories, universe hierarchies are commonly used to increase the expressive power of the theory while avoiding inconsistencies arising from size issues. There are numerous ways to specify universe hierarchies, and theories may…

Logic in Computer Science · Computer Science 2021-11-02 András Kovács

We provide a comprehensive development of the basics of descriptive set theory for non-separable complete metric spaces whose weight is a singular cardinal $\lambda$ of countable confinality. Somewhat unexpectedly, the resulting theory is…

Logic · Mathematics 2025-11-21 Vincenzo Dimonte , Luca Motto Ros

We analyse some aspects of the notion of algebraic exponentiation introduced by the second author [16] and satisfied by the category of groups. We show how this notion provides a new approach to the categorical-algebraic question of the…

Category Theory · Mathematics 2011-12-20 Dominique Bourn , James R. A. Gray

We compare the random group model of Gromov and the model of generic groups of Arzhantseva and Ol'shanskii.

Group Theory · Mathematics 2010-02-08 Ilya Kapovich , Paul Schupp

Gelfand - Na\u{i}mark theorem supplies a one to one correspondence between commutative $C^*$-algebras and locally compact Hausdorff spaces. So any noncommutative $C^*$-algebra can be regarded as a generalization of a topological space.…

Operator Algebras · Mathematics 2014-10-28 Petr Ivankov

This article represents a major step in the unification of the theory of algebraic, topological and singular transition matrices by introducing a definition which is a generalization that encompasses all of the previous three. When this…

Dynamical Systems · Mathematics 2013-11-15 Robert Franzosa , Ketty A. de Rezende , Ewerton R. Vieira