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Related papers: On coalgebra based on classes

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Coalgebras for an endofunctor provide a category-theoretic framework for modeling a wide range of state-based systems of various types. We provide an iterative construction of the reachable part of a given pointed coalgebra that is inspired…

Category Theory · Mathematics 2020-01-15 Thorsten Wißmann , Stefan Milius , Shin-ya Katsumata , Jérémy Dubut

Coalgebras for a functor model different types of transition systems in a uniform way. This paper focuses on a uniform account of finitary logics for set-based coalgebras. In particular, a general construction of a logic from an arbitrary…

Logic in Computer Science · Computer Science 2015-07-01 Alexander Kurz , Jiri Rosicky

We construct recursion categories from categories of coalgebras. Let $F$ be a nontrivial endofunctor on the category of sets that weakly preserves pullbacks and such that the category $\textbf{Set}_F$ of $F$-coalgebras is complete. The…

Category Theory · Mathematics 2007-05-23 Florian Lengyel

It is shown that universal algebras that are injective in their equational classes are characterized by internal property that can be called completeness. We define universal algebra $A$ as complete (closed to simple extensions) if for each…

Commutative Algebra · Mathematics 2021-12-14 Pavlo Dzikovskyi

This paper contributes to a theory of the behaviour of "finite-state" systems that is generic in the system type. We propose that such systems are modeled as coalgebras with a finitely generated carrier for an endofunctor on a locally…

Category Theory · Mathematics 2017-10-23 Stefan Milius , Dirk Pattinson , Thorsten Wißmann

The theory of coalgebras, for an endofunctor on a category, has been proposed as a general theory of transition systems. We investigate and relate four generalizations of bisimulation to this setting, providing conditions under which the…

Logic in Computer Science · Computer Science 2015-07-01 Sam Staton

In this article, we combine Sweedler's classic theory of measuring coalgebras -- by which $k$-algebras are enriched in $k$-coalgebras for $k$ a field -- with the theory of W-types -- by which the categorical semantics of inductive data…

Category Theory · Mathematics 2024-05-24 Lukas Mulder , Paige Randall North , Maximilien Péroux

In previous work, categories of algebras of endofunctors were shown to be enriched in categories of coalgebras of the same endofunctor, and the extra structure of that enrichment was used to define a generalization of inductive data types.…

Category Theory · Mathematics 2026-03-03 Lukas Mulder , Paige Randall North , Maximilien Péroux

We show that a class of algebras is closed under the taking of homomorphic images and direct products if and only if the class consists of all algebras that satisfy a set of (generally simultaneous) equations. For classes of regular…

Group Theory · Mathematics 2022-06-23 Peter M Higgins , Marcel Jackson

Recursive coalgebras provide an elegant categorical tool for modelling recursive algorithms and analysing their termination and correctness. By considering coalgebras over categories of suitably indexed families, the correctness of the…

Programming Languages · Computer Science 2026-04-20 Cass Alexandru , Henning Urbat , Thorsten Wißmann

The free algebra adjunction, between the category of algebras of a monad and the underlying category, induces a comonad on the category of algebras. The coalgebras of this comonad are the topic of study in this paper (following earlier…

Logic in Computer Science · Computer Science 2015-07-01 Bart Jacobs

The main result is Theorem: Let A be an R-algebra, mu, lambda be cardinals such that |A|<=mu=mu^{aleph_0}<lambda<=2^mu. If A is aleph_0-cotorsion-free or A is countably free, respectively, then there exists an aleph_0-cotorsion-free or a…

Rings and Algebras · Mathematics 2007-05-23 Rüdiger Göbel , Saharon Shelah

An old theorem of Ad\'amek constructs initial algebras for sufficiently cocontinuous endofunctors via transfinite iteration over ordinals in classical set theory. We prove a new version that works in constructive logic, using "inflationary"…

Logic · Mathematics 2022-11-04 Andrew M. Pitts , S. C. Steenkamp

Directed spaces are natural topological extensions of dcpos in domain theory and form a cartesian closed category. In order to model nondeterministic semantics, the power structures over directed spaces were defined through the form of free…

Category Theory · Mathematics 2022-09-12 Yuxu Chen , Hui Kou

We show that the category of comodules over a coassociative coalgebra in a complete, cocomplete and well-powered category has limits and colimits under additional assumptions.

Category Theory · Mathematics 2013-12-06 Anton Lyubinin

We study many-valued coalgebraic logics with semi-primal algebras of truth-degrees. We provide a systematic way to lift endofunctors defined on the variety of Boolean algebras to endofunctors on the variety generated by a semi-primal…

Logic in Computer Science · Computer Science 2024-08-07 Alexander Kurz , Wolfgang Poiger , Bruno Teheux

Expanding upon recent work, a new class of $A$-functions is introduced that can be viewed as an appropriate generalization of the class of regular $A$-functions, the class of structured $A$-functions, and the class of perfect $A$-functions.…

Number Theory · Mathematics 2022-03-01 Joseph Burnett , Alex Taylor

We present a collection of results that imply that an endofunctor on a category has a terminal object obtainable as a countable limit of its terminal-coalgebra chain. This holds for finitary endofunctors preserving nonempty binary…

Logic in Computer Science · Computer Science 2025-09-03 Jiří Adámek , Stefan Milius , Lawrence S. Moss

Kurz et al. have recently shown that infinite $\lambda$-trees with finitely many free variables modulo $\alpha$-equivalence form a final coalgebra for a functor on the category of nominal sets. Here we investigate the rational fixpoint of…

Category Theory · Mathematics 2015-06-01 Stefan Milius , Thorsten Wißmann

We express the classical $p$-adic integers $\hat{\mathbb{Z}_p}$, as a metric space, as a final colagebra to a certain endofunctor. We realize the addition and the multiplication on $\hat{\mathbb{Z}_p}$ as the coalgebra maps from…

Number Theory · Mathematics 2015-06-05 Prasit Bhattacharya