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Related papers: Delta lenses as coalgebras for a comonad

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A Delta-groupoid is an algebraic structure which axiomitizes the combinatorics of a truncated tetrahedron. It is shown that there are relations of Delta-groupoids to rings, group pairs, and (ideal) triangulations of three-manifolds. In…

Geometric Topology · Mathematics 2009-08-11 R. M. Kashaev

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

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

Lenses have a rich history and have recently received a great deal of attention from applied category theorists. We generalize the notion of lens by defining a category $\mathsf{Lens}_F$ for any category $\mathcal{C}$ and functor $F\colon…

Category Theory · Mathematics 2022-03-18 David I. Spivak

The Dirac delta function is widely used in many areas of physics and mathematics. Here we consider the generalization of a Dirac delta function to allow the use of complex arguments. We show that the properties of a generalized delta…

Quantum Physics · Physics 2018-02-28 R. A. Brewster , J. D. Franson

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

The paper introduces the notion of a weak bisimulation for coalgebras whose type is a monad satisfying some extra properties. In the first part of the paper we argue that systems with silent moves should be modelled coalgebraically as…

Logic in Computer Science · Computer Science 2017-01-11 Tomasz Brengos

Monads are extensively used nowadays to abstractly model a wide range of computational effects such as nondeterminism, statefulness, and exceptions. It turns out that equipping a monad with a (uniform) iteration operator satisfying a set of…

Logic in Computer Science · Computer Science 2016-03-08 Sergey Goncharov , Stefan Milius , Christoph Rauch

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

Two unital operator algebras A, B are called Delta-equivalent if there exists an equivalence functor between the categories A-mod and B-mod which "extends" to a *-functor implementing an equivalence between the categories A-dmod and B-dmod.…

Operator Algebras · Mathematics 2007-09-06 G. K. Eleftherakis

We prove that the free algebra functor associated to a symmetric, pseudo commutative 2-monad, from the underlying symmetric monoidal 2-category to the 2-category of algebras and pseudo maps over the 2-monad can be enhanced to a…

Category Theory · Mathematics 2025-09-19 Diego Manco

Bidirectional transformations (bx) have primarily been modeled as pure functions, and do not account for the possibility of the side-effects that are available in most programming languages. Recently several formulations of bx that use…

Programming Languages · Computer Science 2017-09-12 Faris Abou-Saleh , James Cheney , Jeremy Gibbons , James McKinna , Perdita Stevens

The relative cell complexes with respect to a generating set of cofibrations are an important class of morphisms in any model structure. In the particular case of the standard (algebraic) model structure on $\textbf{Top}$, we give a new…

Category Theory · Mathematics 2013-04-01 Thomas Athorne

We study polynomial comonads and polynomial bicomodules. Polynomial comonads amount to categories. Polynomial bicomodules between categories amount to parametric right adjoint functors between corresponding copresheaf categories. These may…

Category Theory · Mathematics 2026-05-25 David I. Spivak , Richard Garner , Aaron David Fairbanks

As an example of the categorical apparatus of pseudo algebras over 2-theories, we show that pseudo algebras over the 2-theory of categories can be viewed as pseudo double categories with folding or as appropriate 2-functors into…

Category Theory · Mathematics 2011-11-09 Thomas M. Fiore

Bidirectional transformation, also called lens, has played important roles in maintaining consistency in many fields of applications. A lens is specified by a pair of forward and backward functions which relate to each other in a consistent…

Programming Languages · Computer Science 2019-10-24 Keisuke Nakano

For a model category, we prove that taking the category of coalgebras over a comonad commutes with left Bousfield localization in a suitable sense. Then we prove a general existence result for the left-induced model structure on the…

Algebraic Topology · Mathematics 2025-05-28 David White , Donald Yau

An operad describes a category of algebras and a (co)homology theory for these algebras may be formulated using the homological algebra of operads. A morphism of operads $f:\mathcal{O}\rightarrow\mathcal{P}$ describes a functor allowing a…

Rings and Algebras · Mathematics 2014-03-20 James Griffin

Lenses, optics and dependent lenses (or equivalently morphisms of containers, or equivalently natural transformations of polynomial functors) are all widely used in applied category theory as models of bidirectional processes. From the…

Category Theory · Mathematics 2021-12-22 Dylan Braithwaite , Matteo Capucci , Bruno Gavranović , Jules Hedges , Eigil Fjeldgren Rischel

In the first part of the paper we recall the coalgebraic approach to handling the so-called invisible transitions that appear in different state-based systems semantics. We claim that these transitions are always part of the unit of a…

Logic in Computer Science · Computer Science 2014-02-26 Tomasz Brengos