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We classify which dual functors on a unitary multitensor category are compatible with the dagger structure in terms of groupoid homomorphisms from the universal grading groupoid to $\mathbb{R}_{>0}$ where the latter is considered as a…

Quantum Algebra · Mathematics 2018-08-02 David Penneys

A quandle equipped with a good involution is referred to as symmetric. It is known that the cohomology of symmetric quandles gives rise to strong cocycle invariants for classical and surface links, even when they are not necessarily…

Quantum Algebra · Mathematics 2025-10-17 Biswadeep Karmakar , Deepanshi Saraf , Mahender Singh

Using the theory of coalgebra, we introduce a uniform framework for adding modalities to the language of propositional geometric logic. Models for this logic are based on coalgebras for an endofunctor on some full subcategory of the…

Logic · Mathematics 2023-06-22 Nick Bezhanishvili , Jim de Groot , Yde Venema

Classical Gon\v{c}arov polynomials are polynomials which interpolate derivatives. Delta Gon\v{c}arov polynomials are polynomials which interpolate delta operators, e.g., forward and backward difference operators. We extend fundamental…

Combinatorics · Mathematics 2016-10-07 Rudolph Lorentz , Salvatore Tringali , Catherine H. Yan

In category theory, monads, which are monoid objects on endofunctors, play a central role closely related to adjunctions. Monads have been studied mostly in algebraic situations. In this dissertation, we study this concept in some…

Differential Geometry · Mathematics 2014-01-07 Benoît Jubin

Monads are well known to be equivalent to lax functors out of the terminal category. Morita contexts are here shown to be lax functors out of the chaotic category with two objects. This allows various aspects in the theory of Morita…

Category Theory · Mathematics 2014-05-21 Stephen Lack

Pebble games are a powerful tool in the study of finite model theory, constraint satisfaction and database theory. Monads and comonads are basic notions of category theory which are widely used in semantics of computation and in modern…

Logic in Computer Science · Computer Science 2017-04-19 Samson Abramsky , Anuj Dawar , Pengming Wang

We define a new notion of an algebraic model structure, in which the cofibrations and fibrations are retracts of coalgebras for comonads and algebras for monads, and prove "algebraic" analogs of classical results. Using a modified version…

Category Theory · Mathematics 2011-03-14 Emily Riehl

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 present a comonadic approach to pretorsion theories on semiexact categories, i.e. categories equipped with a closed ideal of null morphisms that admits all kernels and all cokernels. We first prove that bihereditary pretorsion theories…

Category Theory · Mathematics 2026-01-19 Elena Caviglia , Zurab Janelidze , Luca Mesiti

In the theory of operads we consider functors of generalized symmetric powers defined by sums of coinvariant modules under actions of symmetric groups. One observes classically that the construction of symmetric functors provides an…

Algebraic Topology · Mathematics 2009-02-25 Benoit Fresse

We build upon our recently introduced concept of an update structure to show that it is a generalisation of very-well-behaved lenses, that is, there is a bijection between a strict subset of update structures and vwb lenses in cartesian…

Quantum Physics · Physics 2021-01-27 Matthew Wilson , James Hefford , Guillaume Boisseau , Vincent Wang

In recent years, algebraic studies of the differential calculus and integral calculus in the forms of differential algebra and Rota-Baxter algebra have been merged together to reflect the close relationship between the two calculi through…

Category Theory · Mathematics 2020-07-27 Li Guo , William Keigher , Shilong Zhang

In "Backprop as functor", the authors show that the fundamental elements of deep learning -- gradient descent and backpropagation -- can be conceptualized as a strong monoidal functor Para(Euc)$\to$Learn from the category of parameterized…

Category Theory · Mathematics 2025-06-09 David I. Spivak

Cartesian differential categories come equipped with a differential combinator that formalizes the derivative from multi-variable differential calculus, and also provide the categorical semantics of the differential $\lambda$-calculus. An…

Category Theory · Mathematics 2023-01-24 Sacha Ikonicoff , Jean-Simon Pacaud Lemay

Every endofunctor of the category of classes is proved to be set-based in the sense of Aczel and Mendler, therefore, it has a final coalgebra. Other basic properties of these endofunctors are proved, e.g. the existence of a free completely…

Logic in Computer Science · Computer Science 2007-05-23 J. Adamek , S. Milius , J. Velebil

The formal system lambda-delta is a typed lambda calculus that pursues the unification of terms, types, environments and contexts as the main goal. lambda-delta takes some features from the Automath-related lambda calculi and some from the…

Logic in Computer Science · Computer Science 2008-09-25 F. Guidi

The belief construction is a fundamental technique for transforming partially observable systems to fully observable ones while preserving the relevant semantics. It plays a central role in the analysis of partially observable systems, in…

Logic in Computer Science · Computer Science 2026-05-19 Mayuko Kori , Kazuki Watanabe

It is shown that the one-lens system in para-axial optics can serve as an optical computer for contraction of Wigner's little groups and an analogue computer which transforms analytically computations on a spherical surface to those on a…

Mathematical Physics · Physics 2009-11-07 S. Baskal , Y. S. Kim

We study non-counital coalgebras and their dual non-unital algebras, and introduce the finite dual of a non-unital algebra. We show that a theory that parallels in good part the duality in the unital case can be constructed. Using this, we…

Representation Theory · Mathematics 2016-01-01 Sorin Dascalescu , Miodrag C. Iovanov