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Functional representations of the capacity monad based on the max and min operations were considered in \cite{Ra1} and \cite{Ny1}. Nykyforchyn considered in \cite{Ny2} some alternative monad structure for the possibility capacity functor…

General Topology · Mathematics 2019-03-05 Taras Radul

We define $A_{\infty}$-structures -- algebras, coalgebras, modules, and comodules -- in an arbitrary monoidal DG category or bicategory by rewriting their definitions in terms of unbounded twisted complexes. We develop new notions of strong…

Category Theory · Mathematics 2023-12-01 Rina Anno , Sergey Arkhipov , Timothy Logvinenko

There is recent interest in compressing data sets for non-sequential settings, where lack of obvious orderings on their data space, require notions of data equivalences to be considered. For example, Varshney & Goyal (DCC, 2006) considered…

Data Structures and Algorithms · Computer Science 2012-10-16 Fabian Lim

Each distributor between categories enriched over a small quantaloid Q gives rise to two adjunctions between the categories of contravariant and covariant presheaves, and hence to two monads. These two adjunctions are respectively…

Category Theory · Mathematics 2013-07-23 Lili Shen , Dexue Zhang

Ultrafilters are very useful and versatile objects with applications throughout mathematics: in topology, analysis, combinarotics, model theory, and even theory of social choice. Proofs based on ultrafilters tend to be shorter and more…

Dynamical Systems · Mathematics 2013-10-17 Jakub Konieczny

A classical theorem of Hutchinson asserts that if an iterated function system acts on $\mathbb{R}^d$ by similitudes and satisfies the open set condition then it admits a unique self-similar measure with Hausdorff dimension equal to the…

Dynamical Systems · Mathematics 2019-09-11 Ian D. Morris , Cagri Sert

We introduce and study Hopf monads on autonomous categories (i.e., monoidal categories with duals). Hopf monads generalize Hopf algebras to a non-braided (and non-linear) setting. Indeed, any monoidal adjunction between autonomous…

Quantum Algebra · Mathematics 2007-05-23 Alain Bruguières , Alexis Virelizier

Varieties of quantitative algebras are fully described by their free-algebra monads on the category Met of metric spaces. For a longer time it has been an open problem whether the resulting enriched monads are precisely the strongly…

Category Theory · Mathematics 2026-02-06 Jiri Adamek

We extend Bourke and Garner's idempotent adjunction between monads and pretheories to the framework of $\infty$-categories and we use this to prove many classical results about monads in the $\infty$-categorical framework. Amongst other…

Category Theory · Mathematics 2021-06-17 Simon Henry , Nicholas J. Meadows

We call a von Neumann algebra with finite dimensional center a multifactor. We introduce an invariant of bimodules over $\rm II_1$ multifactors that we call modular distortion, and use it to formulate two classification results. We first…

Operator Algebras · Mathematics 2025-06-06 Marcel Bischoff , Ian Charlesworth , Samuel Evington , Luca Giorgetti , David Penneys

We introduce pseudoalgebras for relative pseudomonads and develop their theory. For each relative pseudomonad $T$, we construct a free--forgetful relative pseudoadjunction that exhibits the bicategory of $T$-pseudoalgebras as terminal among…

Category Theory · Mathematics 2025-01-23 Nathanael Arkor , Philip Saville , Andrew Slattery

We develop first steps in the study of factorizations of elements in ultraproducts of commutative cancellative monoids into irreducible elements. A complete characterization of the (multi-)sets of lengths in such objects is given. As…

Commutative Algebra · Mathematics 2023-11-29 Daniel Windisch

Containers are used to carve out a class of strictly positive data types in terms of shapes and positions. They can be interpreted via a fully-faithful functor into endofunctors on Set. Monadic containers are those containers whose…

Logic in Computer Science · Computer Science 2025-06-16 Chris Purdy , Stefania Damato

Let $\mathbb{A}$ be a $2$-category with suitable opcomma objects and pushouts. We give a direct proof that, provided that the codensity monad of a morphism $p$ exists and is preserved by a suitable morphism, the factorization given by the…

Category Theory · Mathematics 2023-11-13 Fernando Lucatelli Nunes

We use weighted polynomial approximation to prove the existence of a compact set K with non-empty interior and a function f is dense in the space A(K) of all continuous functions on K that are holomorphic in the interior of K, endowed with…

Complex Variables · Mathematics 2025-06-26 Stéphane Charpentier , Konstantinos Maronikolakis

The behaviour of limits of weak morphisms in 2-dimensional universal algebra is not 2-categorical in that, to fully express the behaviour that occurs, one needs to be able to quantify over strict morphisms amongst the weaker kinds.…

Category Theory · Mathematics 2022-01-31 John Bourke

We exhibit an adjunction between a category of abstract algebras of partial functions and a category of set quotients. The algebras are those atomic algebras representable as a collection of partial functions closed under relative…

Logic · Mathematics 2022-06-15 Célia Borlido , Brett McLean

We extend the Euler's totient function (from arithmetic) to any irreducible subfactor planar algebra, using the Mobius function of its biprojection lattice, as Hall did for the finite groups. We prove that if it is nonzero then there is a…

Operator Algebras · Mathematics 2018-03-30 Sebastien Palcoux

We categorify cocompleteness results of monad theory, in the context of pseudomonads. We first prove a general result establishing that, in any 2-category, weighted bicolimits can be constructed from oplax bicolimits and bicoequalizers of…

Category Theory · Mathematics 2023-02-15 Axel Osmond

In this work, we establish certain enrichments of dual algebraic structures in the setting of monoidal double categories. In more detail, we obtain a tensored and cotensored enrichment of monads in comonads, as well as a tensored and…

Category Theory · Mathematics 2025-02-04 Vasileios Aravantinos-Sotiropoulos , Christina Vasilakopoulou
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