The Nerve of a Small Category and the Fundamental Groupoid of a Simplicial Set

I have begun organizing, this semester, a category theory seminar. So far we have developed the basics of Kan extensions and coends, and started to discuss simplicial sets. It has quickly become clear to me that we could easily spend the rest of the semester on the theory of simplicial sets.

Since the coronavirus shut the school's operation down, we have moved online. So here is my first video lecture. More to come soon! The next one on the geometry of simplicial sets and the Eilenberg-Zilber theorem.

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