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Related papers: Codensity and the ultrafilter monad

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Codensity monads provide a universal method to generate complex monads from simple functors. Recently, a wide range of important monads in logic, denotational semantics, and probabilistic computation, such as several incarnations of the…

Logic in Computer Science · Computer Science 2026-03-10 Fabian Lenke , Nico Wittrock , Stefan Milius , Henning Urbat

For a number of locally finitely presentable categories K we describe the codensity monad of the full embedding of all finitely presentable objects into K. We introduce the concept of D-ultrafilter on an object, where D is a "nice"…

Category Theory · Mathematics 2020-10-26 Jirí Adámek , Lurdes Sousa

Coproducts of monads on Set have arisen in both the study of computational effects and universal algebra. We describe coproducts of consistent monads on Set by an initial algebra formula, and prove also the converse: if the coproduct…

Logic in Computer Science · Computer Science 2014-09-15 Jiří Adámek , Nathan Bowler , Paul B. Levy , Stefan Milius

The Giry monad on the category of measurable spaces sends a space to a space of all probability measures on it. There is also a finitely additive Giry monad in which probability measures are replaced by finitely additive probability…

Category Theory · Mathematics 2017-08-04 Tom Avery

We study codensity monads $T$ induced by (mostly small, mostly dense) full subcategories $A \subset K$. These monads behave quite similarly, we show some connections with the Isbell duality, pro-finite objects and compact spaces. We prove…

Category Theory · Mathematics 2025-08-05 Ivan Di Liberti

Our work over the past years shows that not only the collection of (for instance) all topological spaces gives rise to a category, but also each topological space can be seen individually as a category by interpreting the convergence…

Category Theory · Mathematics 2008-04-03 Dirk Hofmann

We show from a categorical point of view that probability measures on certain measurable or topological spaces arise canonically as the extension of probability distributions on countable sets. We do this by constructing probability monads…

Category Theory · Mathematics 2022-06-23 Ruben Van Belle

The inclusion hyperspace functor, the capacity functor and monads for these functors have been extended from the category of compact Hausdorff spaces to the category of Tychonoff spaces. Properties of spaces and maps of inclusion…

Category Theory · Mathematics 2010-08-31 Oleh Nykyforchyn , Dušan Repovš

It is known that the so-called monadic decomposition, applied to the adjunction connecting the category of bialgebras to the category of vector spaces via the tensor and the primitive functors, returns the usual adjunction between…

Category Theory · Mathematics 2021-02-15 Alessandro Ardizzoni , Claudia Menini

The category of all monads over many-sorted sets (and over other "set-like" categories) is proved to have coequalizers and strong cointersections. And a general diagram has a colimit whenever all the monads involved preserve monomorphisms…

Logic in Computer Science · Computer Science 2014-09-15 Jiří Adámek

We introduce a generalization of monads, called relative monads, allowing for underlying functors between different categories. Examples include finite-dimensional vector spaces, untyped and typed lambda-calculus syntax and indexed…

Programming Languages · Computer Science 2015-09-14 Thosten Altenkirch , James Chapman , Tarmo Uustalu

We introduce dicodensity monads: a generalisation of pointwise codensity monads generated by functors to monads generated by mixed-variant bifunctors. Our construction is based on the notion of strong dinaturality (also known as Barr…

Logic in Computer Science · Computer Science 2026-03-03 Maciej Piróg , Filip Sieczkowski

We study a composition operation on monads, equivalently presented as large equational theories. Specifically, we discuss the existence of tensors, which are combinations of theories that impose mutual commutation of the operations from the…

Logic in Computer Science · Computer Science 2015-07-01 Nathan Bowler , Sergey Goncharov , Paul Blain Levy , Lutz Schröder

This paper uses monads and comonads to establish a certain type of equivalence between two subcategories, one reflective and one coreflective, in a category whose objects represent compactifications of non-compact locally compact Hausdorff…

Operator Algebras · Mathematics 2026-01-14 Jeri Ann Spiker

In the context of abstract coinduction in complete lattices, the notion of compatible function makes it possible to introduce enhancements of the coinduction proof principle. The largest compatible function, called the companion, subsumes…

Logic in Computer Science · Computer Science 2023-06-22 Damien Pous , Jurriaan Rot

We use nonstandard methods, based on iterated hyperextensions, to develop applications to Ramsey theory of the theory of monads of ultrafilters. This is performed by studying in detail arbitrary tensor products of ultrafilters, as well as…

Logic · Mathematics 2017-12-19 Lorenzo Luperi Baglini

In the article \cite{Sim}, H. Simmons describes two monads of interests arising from the dual adjunction between the category of topological spaces and that of (bounded) distributive lattices. These are the open prime filter monad and the…

Category Theory · Mathematics 2025-08-01 Ando Razafindrakoto

We study lax functors between bicategories as a generalized concept of monads and describe generalized notions and theorems of formal monad theory for lax functors. Our first approach is to use the 2-monad whose lax algebras are lax…

Category Theory · Mathematics 2024-09-20 Kengo Hirata

The goal of this paper is to prove coherence results with respect to relational graphs for monoidal monads and comonads, i.e. monads and comonads in a monoidal category such that the endofunctor of the monad or comonad is a monoidal functor…

Category Theory · Mathematics 2010-01-08 K. Dosen , Z. Petric

We consider isomorphism between the idempotent measure monad based on the maximum and the addition operations and the idempotent measure monad based on the maximum and the multiplication operations. A one of the consequences of this result…

General Topology · Mathematics 2023-10-24 Taras Radul
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