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Recent work in set theory indicates that there are many different notions of 'set', each captured by a different collection of axioms, as proposed by J. Hamkins in [Ham11]. In this paper we strive to give one class theory that allows for a…

Logic · Mathematics 2022-06-10 Alec Rhea

The basic notions of category theory, such as limit, adjunction, and orthogonality, all involve assertions of the existence and uniqueness of certain arrows. Weak notions arise when one drops the uniqueness requirement and asks only for…

Category Theory · Mathematics 2012-05-25 Stephen Lack , Jiri Rosicky

We propose a categorical framework to reason about scientific explanations: descriptions of a phenomenon meant to translate it into simpler terms, or into a context that has been already understood. Our motivating examples come from systems…

Logic in Computer Science · Computer Science 2023-08-01 Leo Lobski , Fabio Zanasi

In recent years the theory of dendroidal sets has emerged as an important framework for higher algebra. In this article we introduce the concept of a $C^*$-algebraic drawing of a dendroidal set. It depicts a dendroidal set as an object in…

Operator Algebras · Mathematics 2019-05-29 Snigdhayan Mahanta

The category of affine schemes is a tangent category whose tangent bundle functor is induced by K\"ahler differentials, providing a direct link between algebraic geometry and tangent category theory. Moreover, this tangent bundle functor is…

Category Theory · Mathematics 2026-04-21 Marcello Lanfranchi , Jean-Simon Pacaud Lemay

The well-known difficulties arising in a classification which is not set-theoretically trivial---involving what is sometimes called a non-smooth quotient---have been overcome in a striking way in the theory of operator algebras by the use…

Operator Algebras · Mathematics 2007-11-21 George A. Elliott

Categories, n-categories, double categories, and multicategories (among others) all have similar definitions as collections of cells with composition operations. We give an explicit description of the information required to define any…

Category Theory · Mathematics 2025-06-03 Brandon Shapiro

We give a sufficient condition for an Ext-finite triangulated category to be saturated. Saturatedness means that every contravariant cohomological functor of finite type to vector spaces is representable. The condition consists in existence…

Algebraic Geometry · Mathematics 2007-05-23 Alexei Bondal , Michel Van den Bergh

Functorial semi-norms are semi-normed refinements of functors such as singular (co)homology. We investigate how different types of representability affect the (non-)triviality of finite functorial semi-norms on certain functors or classes.…

Algebraic Topology · Mathematics 2015-09-08 Clara Loeh

A representation of an object in a category is an abelian group in the corresponding comma category. In this paper we derive the formulas describing linear representations of objects in the category of formal loops and apply them to obtain…

Representation Theory · Mathematics 2015-03-25 S. Madariaga , José M. Pérez-Izquierdo

We define a category $\mathsf{List}$ whose objects are sets and morphisms are mappings which assign to an element in the domain an ordered sequence (list) of elements in the codomain. We introduce and study a category of simplicial objects…

Algebraic Topology · Mathematics 2025-11-04 Redi Haderi , Özgün Ünlü

Function graphs are graphs representable by intersections of continuous real-valued functions on the interval [0,1] and are known to be exactly the complements of comparability graphs. As such they are recognizable in polynomial time.…

Data Structures and Algorithms · Computer Science 2012-05-01 Pavel Klavík , Jan Kratochvíl , Tomasz Krawczyk , Bartosz Walczak

Morphisms in a monoidal category are usually interpreted as processes, and graphically depicted as square boxes. In practice, we are faced with the problem of interpreting what non-square boxes ought to represent in terms of the monoidal…

Category Theory · Mathematics 2022-02-22 Mario Román

Functor morphing provides a method to translate complex representations of automorphism groups of finite modules over finite rings to representations of automorphism groups of functors in some abelian category. In this paper we give an…

Representation Theory · Mathematics 2026-03-30 Ehud Meir

We provide a new approach to categorical graph and hypergraph theory by using categorical syntax and semantics. For each monoid $M$ and action on a set $X$, there is an associated presheaf topos of $(X,M)$-graphs where each object can be…

Combinatorics · Mathematics 2019-07-08 Martin Schmidt

Twisted diagrams are "diagrams" with components in different categories. Structure maps are defined using auxiliary data which consists of functors relating the various categories to each other. Prime examples of the construction are…

Algebraic Topology · Mathematics 2008-05-28 Thomas Huettemann , Oliver Roendigs

Since categories are graphs with additional "structure", one should start from fuzzy graphs in order to define a theory of fuzzy categories. Thus is makes sense to introduce categories whose morphisms are associated with a plausibility…

Logic in Computer Science · Computer Science 2014-10-07 Apostolos Syropoulos

We introduce the combinatorial notion of a $q$-fatorization graph intended as a tool to study and express results related to the classification of prime simple modules for quantum affine algebras. These are directed graphs equipped with…

Representation Theory · Mathematics 2024-06-12 Adriano Moura , Clayton Silva

A representation embedding between cartesian theories can be defined to be a functor between respective categories of models that preserves finitely-generated projective models and that preserves and reflects certain epimorphisms. This…

Representation Theory · Mathematics 2017-11-09 Michael Lambert

This is the second paper in a series. In part I we developed deformation theory of objects in homotopy and derived categories of DG categories. Here we extend these (derived) deformation functors to an appropriate bicategory of artinian DG…

Algebraic Geometry · Mathematics 2018-08-13 Alexander I. Efimov , Valery A. Lunts , Dmitri O. Orlov