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5 votes
0 answers
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Bicategories in which the composition functors $\circ_{A, B, C}$ admit right adjoints

In Bénabou's 1967 Introduction to Bicategories, he mentions that, in a forthcoming part II, he would study bicategories $\mathcal K$ in which each composition functor $$\circ_{A, B, C} \colon \mathcal ...
varkor's user avatar
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5 votes
1 answer
300 views

3-functoriality of the lax Gray tensor product

In Formal category theory: adjointness for 2-categories, Gray defines a tensor product of 2-categories, now more commonly known as the lax Gray tensor product, which I will denote by $\otimes_l$. For ...
varkor's user avatar
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2 votes
0 answers
71 views

2-morphism between circuits in a monoidal category

We are used to seeing equations between circuits in monoidal categories like this I am wondering about morphisms between string diagrams. I think they are 2-cells. I found an example of a 2-cell ...
mathlete42's user avatar
7 votes
0 answers
184 views

Strictifying monoidal 2-functors

Let $F:\mathcal{C}\rightarrow\mathcal{D}$ be a (weak) monoidal 2-functor between two strict monoidal 2-categories. Up to replacing $\mathcal{C}$ by an equivalent strict monoidal 2-category, can I ...
JeCl's user avatar
  • 1,001
4 votes
0 answers
95 views

Coherence for closed bicategories

A right-closed bicategory [1] is a bicategory that has all right extensions (i.e. right adjoints to precomposition with a fixed 1-cell). A one-object right-closed bicategory is therefore a right-...
varkor's user avatar
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7 votes
0 answers
428 views

Left Kan extensions of "strong" monoidal functors

Consider the 2-category $\mathsf{MonCat}$ where objects are monoidal categories, 1-cells are strong monoidal functors, and 2-cells are monoidal natural transformations. Given arrows $f: \mathsf{C} \to ...
Eigil Fjeldgren Rischel's user avatar
3 votes
1 answer
187 views

On the Group Structure of Morphism Set of a Strict 2-Group

The standard definition of a strict 2-group says that it is a strict monoidal category in which every morphism is invertible and each object has a strict inverse. Also it is a well known fact that a ...
Adittya Chaudhuri's user avatar
8 votes
2 answers
472 views

How to construct a free 2-group on a groupoid?

Let G be a groupoid. I'm wondering how to construct the free 2-group on G. By the free 2-group I mean a 2-group $\mathcal{F}\left(G\right)$ equipped with a functor $i:G\longrightarrow\mathcal{F}\...
Tom Johnson's user avatar
8 votes
1 answer
530 views

Is a weak monoidal category a monoid object in some category?

A monoid in the Category Cat is a strict monoidal category according to Wikipedia. Is it possible to weaken the monoid so that its realisation in Cat is a weak monoidal category? Do we shift up a ...
Shamim's user avatar
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