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For questions involving one or more categorical dimensions, or involving homotopy coherent categorical structures.

7 votes

Generalizing $n$ for $n$-categories

Here are some things I know of that looks like this: I* have argued here that it is possible to extend the notion of strict $\infty$-category to a notion of $P$-category for any poset $P$. At this po …
Simon Henry's user avatar
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13 votes
Accepted

Why are finite cell complexes also finite as infinity-categories?

Start from a finite simplicial set $K$ which is homotopicaly equivalent to a Kan complex $X$. Then by applying a finite number of pushout of outer horn inclusion to $K$, you can build homotopy equiva …
Simon Henry's user avatar
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3 votes

Is the inclusion functor from gaunt strict $n$-categories to weak $(\infty,n)$-categories fu...

I will see an $(\infty,\infty)$-category as a functor $\Theta^{op} \to \text{Space}$ that satisfies the usual Segal condition, i.e., i.e. preserve the pushouts encoding the various type of composition …
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12 votes
2 answers
613 views

n-categorical pasting diagram overview

There has been a lots of approaches to the notion of n-categorical diagram and n-categorical pasting diagram: Street : "Parity complexes" Power : " An n-categorical pasting theorem" Johnson : "The …
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7 votes

The category of groupoids vs the category of sets

An important distinction in the "set case" is that there are two things you can refer to when talking about "the category of groupoids": the 1-category of groupoids. the 2-category of groupoids. It …
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5 votes

Which free strict $\omega$-categories are also free as weak $(\infty,\infty)$-categories?

If you don't mind, I'll talk about strinct $\infty$-categories, but weak $(\infty,n)$-category to avoid discussing the 'problem' regarding the non uniqueness of the meaning of $(\infty,\infty)$-catego …
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10 votes
Accepted

Remark 5.4.2.15 in HTT

He is applying 5.4.2.13 to $C$ and not to $D$: Because $C^\kappa$ is essentially small, and each $F(c)$ is $\lambda_c$-compact for some $\lambda$; there is a $\kappa = \sup_{c \in C^\kappa} \lambda_c$ …
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14 votes
Accepted

Higher $\infty$-categories

Using Street's "one type" definition of strict $\infty$-category one can see that the concept of "strict $P$-category" makes sense not justs for any ordinals $P$ but in fact for any posets $P$ (though …
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5 votes
Accepted

Is every folk cofibration of strict $\omega$-categories a monomorphism?

I just thought (or maybe remember) a neat proof of this fact. It involve ideas I worked on a few years ago but never published - but that's short enough so that I can explain the key ideas on MO. Let …
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5 votes
Accepted

Is there a "geometric definition" of globular $\infty$-groupoids/categories?

In short there isn't: the problem is that if you just have globular sets - and if you want $k$-cells to model $k$-arrows following the globular structure - then globular sets have no way of expressing …
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15 votes
1 answer
485 views

Well pointed endofunctors on $\infty$-categories

In $1$-category theory, a well pointed endofunctor of a category $C$, is an endofunctor $F:C \rightarrow C$ endowed with a natural transformation $\sigma : Id \rightarrow F$ such that the two natural …
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4 votes

Are $\infty$-categories functorially colimits of their simplices?

This is just an expended version of the comment. The answer to the question as asked is no. The problem is that for any ($\infty$-)category $J$ the category $D_J$ of functors $J \to Cat_\infty$ that a …
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9 votes

Is there a good general definition of "sheaves with values in a category"?

$\newcommand\Set{\mathrm{Set}}$The naïve definition of sheaves is very well behaved if you look at functoriality in the $f_*$ direction: Of course, you are going to need to assume that $\mathcal{A}$ h …
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13 votes

Correspondence between classes of model categories and classes of $\infty$-categories

Regarding (1) : A) Every model category has an associated $\infty$-category, obtained for example by taking the Dwyer-Kan localization at the class of all equivalence, (But there are other more expli …
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5 votes

When is the category of sheaves on a site compactly assembled/a continuous category?

As far as I'm aware, no such conditions is known - The paper of Anel and Lejay is the closest to an answer available in the litterature. So, this is not an answer to the question, but more of an expan …
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