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Related papers: Tannaka-Krein duality for finite 2-groups

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We develop a general theory of (extended) inner autoequivalences of objects of any 2-category, generalizing the theory of isotropy groups to the 2-categorical setting. We show how dense subcategories let one compute isotropy in the presence…

Category Theory · Mathematics 2024-05-28 Pieter Hofstra , Martti Karvonen

We classify all finite 2-groups that have a cyclic or dihedral maximal subgroup and determine their automorphism groups. Based on this result, we classify all pairs $ (G,\mathcal{M}) $, such that $ G $ is a finite 2-group and $ \mathcal{M}…

Group Theory · Mathematics 2025-08-11 Peice Hua

We define locally wide finitary 2-categories by relaxing the definition of finitary 2-categories to allow infinitely many objects and isomorphism classes of 1-morphisms and infinite dimensional hom-spaces of 2-morphisms. After defining…

Category Theory · Mathematics 2021-06-24 James Macpherson

In this work, we employ the Tannaka-Krein reconstruction to compute the quantum double $\mathcal D(\mathcal G)$ of a finite 2-group $\mathcal G$ as a Hopf monoidal category. We also construct a 3+1D lattice model from the Dijkgraaf-Witten…

Mathematical Physics · Physics 2026-03-17 Mo Huang

Tannaka's Theorem states that a linear algebraic group G is determined by the category of finite dimensional G-modules and the forgetful functor. We extend this result to linear differential algebraic groups by introducing a category…

Representation Theory · Mathematics 2009-02-25 Alexey Ovchinnikov

A natural question in the theory of Tannakian categories is: What if you don't remember $\Forget$? Working over an arbitrary commutative ring $R$, we prove that an answer to this question is given by the functor represented by the \'etale…

Category Theory · Mathematics 2019-11-05 Alexandru Chirvasitu , Theo Johnson-Freyd

A group $G$ is said to be totally $2$-closed if in each of its faithful permutation representations, say on a set $\Omega$, $G$ is the largest subgroup of $\mathrm{Sym}(\Omega)$ which leaves invariant each of the $G$-orbits for the induced…

Group Theory · Mathematics 2021-11-05 Majid Arezoomand , Mohammad A. Iranmanesh , Cheryl E. Praeger , Gareth Tracey

Given a 2-category $\twocat{K}$ admitting a calculus of bimodules, and a 2-monad T on it compatible with such calculus, we construct a 2-category $\twocat{L}$ with a 2-monad S on it such that: (1)S has the adjoint-pseudo-algebra property.…

Category Theory · Mathematics 2007-05-23 Claudio Hermida

Let $\widehat{\mathbb{F}\mathbb{S}et}$ be the groupoid of finite sets and bijections between them equipped with the canonical symmetric rig category structure given by the disjoint union and the cartesian product of finite sets. We prove…

Category Theory · Mathematics 2020-04-21 Josep Elgueta

We introduce a new approach to the study of finite-dimensional representations of the quantum group of the affine Lie superalgebra $\mathrm{L}\mathfrak{gl}_{M|N}=\mathbb{C}[t,t^{-1}]\otimes\mathfrak{gl}_{M|N}$ ($M\neq N$). We explain how…

Representation Theory · Mathematics 2021-07-27 Jae-Hoon Kwon , Sin-Myung Lee

Given a finite dimensional Hilbert space H and a collection of operators between its tensor powers satisfying certain properties, we give a category-free proof of the existence of a compact quantum group G with a fundamental representation…

Operator Algebras · Mathematics 2016-02-17 Sara Malacarne

We generalize the classical Tanaka result on the finiteness of symmetry algebra for non-degenerate pseudo-product structures to the case when the completely-integrable distributions defining the pseudo-product structure are no longer…

Differential Geometry · Mathematics 2026-05-19 Boris Doubrov , Igor Zelenko

Given an action of a finite group G on a fusion category C we give a criterion for the category of G-equivariant objects in C to be group-theoretical, i.e., to be categorically Morita equivalent to a category of group-graded vector spaces.…

Quantum Algebra · Mathematics 2009-05-19 Dmitri Nikshych

We construct the duality groups for N=2 Supersymmetric QCD with gauge group SU(2n+1) and N_f=4n+2 hypermultiplets in the fundamental representation. The groups are generated by two elements $S$ and $T$ that satisfy a relation…

High Energy Physics - Theory · Physics 2009-10-31 Joseph A. Minahan

We show that fusion categories $\Rep(\ku^{\sigma}_{\tau} \Tc)$ of representations of the weak Hopf algebra coming from a vacant double groupoid $\Tc$ and a pair $(\sigma, \tau)$ of compatible 2-cocyles are group-theoretical.

Quantum Algebra · Mathematics 2007-05-23 Juan Martin Mombelli , Sonia Natale

We classify those 2-groups G which factorise as a product of two disjoint cyclic subgroups A and B, transposed by an automorphism of order 2. The case where G is metacyclic having been dealt with elsewhere, we show that for each e>2 there…

Group Theory · Mathematics 2011-12-13 Shaofei Du , Gareth Jones , Jin Ho Kwak , Roman Nedela , Martin Skoviera

A strict 2-group is a 2-category with one object in which all morphisms and all 2-morphisms have inverses. 2-Groups have been studied in the context of homotopy theory, higher gauge theory and Topological Quantum Field Theory (TQFT). In the…

Quantum Algebra · Mathematics 2007-06-13 Hendryk Pfeiffer

We present a categorical point of view on dynamical quantum groups in terms of categories of Harish-Chandra bimodules. We prove Tannaka duality theorems for forgetful functors into the monoidal category of Harish-Chandra bimodules in terms…

Representation Theory · Mathematics 2020-08-25 Artem Kalmykov , Pavel Safronov

We consider semisimple super Tannakian categories generated by an object whose symmetric or alternating tensor square is simple up to trivial summands. Using representation theory, we provide a criterion to identify the corresponding…

Representation Theory · Mathematics 2015-10-01 Thomas Krämer , Rainer Weissauer

We establish several strengthened versions of Lurie's Tannaka duality theorem for certain classes of spectral algebraic stacks. Our most general version of Tannaka duality identifies maps between stacks with exact symmetric monoidal…

Algebraic Geometry · Mathematics 2015-07-08 Bhargav Bhatt , Daniel Halpern-Leistner