New posts in Groupoids

Properties of the Category of topological spaces with $n$ basepoints.

What structure does the alternating group preserve?

Non-commutative duality I: Which C*-algebras are (isomorphic to a) convolution algebra?

On fundamental groupoid of fundamental groupoid

Why did Voevodsky consider categories "posets in the next dimension", and groupoids the correct generalisation of sets?

What are Lie groupoids intuitively?

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

Groupoids and hypergroups

Automorphism groups and etale topological stacks

Groupoid actions on spaces