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We investigate the existence of left and right adjoints to the restriction functor in three categories of continuous representations of a topological group: discrete, linear complete and compact.

Representation Theory · Mathematics 2018-01-09 Katerina Hristova

In this article we extend evaluations of the Kauffman bracket on regular isotopy classes of knots and links to a variety of functors defined on the category of framed tangles. We show that many such functors exist, and that they correspond…

Geometric Topology · Mathematics 2007-05-23 John Armstrong

We consider the problem of constructing the free bifibration generated by a functor of categories $p : D \to C$. This problem was previously considered by Lamarche, and is closely related to the problem, considered by Dawson, Par\'e, and…

Category Theory · Mathematics 2026-01-16 Bryce Clarke , Gabriel Scherer , Noam Zeilberger

Since categories are graphs with additional "structure", one should start from fuzzy graphs in order to define a theory of fuzzy categories. Thus is makes sense to introduce categories whose morphisms are associated with a plausibility…

Logic in Computer Science · Computer Science 2014-10-07 Apostolos Syropoulos

Given a DG-category A we introduce the bar category of modules Modbar(A). It is a DG-enhancement of the derived category D(A) of A which is isomorphic to the category of DG A-modules with A-infinity morphisms between them. However, it is…

Category Theory · Mathematics 2020-03-03 Rina Anno , Timothy Logvinenko

We study polynomial functors over locally cartesian closed categories. After setting up the basic theory, we show how polynomial functors assemble into a double category, in fact a framed bicategory. We show that the free monad on a…

Category Theory · Mathematics 2015-05-13 Nicola Gambino , Joachim Kock

We give conditions of an extension of a free group to be hyperbolic and relatively hyperbolic using the dynamics of the action of $\out$ on the complex of free factors combined with the weak attraction theory. We work with subgroups of…

Group Theory · Mathematics 2025-11-05 Pritam Ghosh , Funda Gültepe

The theory of associative $n$-categories has recently been proposed as a strictly associative and unital approach to higher category theory. As a foundation for a proof assistant, this is potentially attractive, since it has the potential…

Logic in Computer Science · Computer Science 2022-05-19 Lukas Heidemann , David Reutter , Jamie Vicary

Certain results involving "higher structures" are not currently accessible to computer formalization because the prerequisite $\infty$-category theory has not been formalized. To support future work on formalizing $\infty$-category theory…

Category Theory · Mathematics 2025-07-23 Mario Carneiro , Emily Riehl

We want to replace categories, functors and natural transformations by categories, open functors and open natural transformations. In analogy with open dynamical systems, the adjective open is added here to mean that some external…

Category Theory · Mathematics 2021-02-17 Alexandre Fernandez , Luidnel Maignan , Antoine Spicher

Using quilted Floer cohomology and relative quilt invariants, we define a composition functor for categories of Lagrangian correspondences in monotone and exact symplectic Floer theory. We show that this functor agrees with geometric…

Symplectic Geometry · Mathematics 2015-03-13 Katrin Wehrheim , Chris T. Woodward

There is some consensus among orthodox category theorists that the concept of adjoint functors is the most important concept contributed to mathematics by category theory. We give a heterodox treatment of adjoints using heteromorphisms…

Category Theory · Mathematics 2015-08-18 David Ellerman

This article is first in a series of papers where we reprove the statements in constructing the Enhanced Operation Map and the abstract six-functor formalism developed by Liu-Zheng. In this paper, we prove a theorem regarding constructing…

Algebraic Geometry · Mathematics 2025-01-28 Chirantan Chowdhury

Given a right adjoint functor between triangulated categories and an object in the target category, we show that the unit map of adjunction on that object is a split monomorphism if and only if the object belongs to the additive closure of…

Algebraic Geometry · Mathematics 2024-05-13 Souvik Dey

Category theory has foundational importance because it provides conceptual lenses to characterize what is important in mathematics. Originally the main lenses were universal mapping properties and natural transformations. In recent decades,…

Category Theory · Mathematics 2007-05-23 David Ellerman

We extend Lurie's definition of enriched $\infty$-categories to notions of left enriched, right enriched and bienriched $\infty$-categories, which generalize the concepts of closed left tensored, right tensored and bitensored…

Category Theory · Mathematics 2025-08-22 Hadrian Heine

Given a pair of adjoint functors between two arbitrary categories it induces mutually inverse equivalences between the full subcategories of the initial ones, consisting of objects for which the arrows of adjunction are isomorphisms. We…

Category Theory · Mathematics 2009-10-22 George Ciprian Modoi

In this work, we investigate an effective method for showing that functors between categories are left adjoints. The method applies to a large class of categories, namely locally finitely presentable categories, which are ubiquitous in…

Category Theory · Mathematics 2025-01-28 Simon Forest

A notion of a coring extension is defined and it is related to the existence of an additive functor between comodule categories that factorises through forgetful functors. This correspondence between coring extensions and factorisable…

Rings and Algebras · Mathematics 2008-07-31 Tomasz Brzezinski

We prove an unstraightening result for lax transformations between functors from an arbitrary $(\infty,2)$-category to that of $(\infty,2)$-categories. We apply this to study partially (op)lax and weighted (co)limits, giving fibrational…

Category Theory · Mathematics 2024-04-08 Fernando Abellán , Andrea Gagna , Rune Haugseng