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JS PL (he/him) (Dec 08 2025 at 09:13):The Pacific Category Theory (PCT) seminar is a new online seminar for the category theory community in the Asia-Pacific time zone and beyond.
It will run once or twice a month on Fridays at 10am JST/12pm AED (1am UTC).
The first talk will be given by Richard Garner (Macquarie University) on
Title: Universal enrichments
Abstract: For a given category C, there are all sorts of things we might enrich it in. For example, the category of complex vector spaces can be enriched in commutative monoids, or abelian groups, or real vector spaces, or complex vector spaces. In this talk, we explain how, for any locally presentable category C, there is a universal locally presentable monoidal category V in which it can be enriched. The fun part is trying to calculate V for particular choices of C; in general, it is rather intractable but sometimes we get lucky!
The zoom link will be posted on the website https://pctseminar.github.io/ shortly before the talk.
Kevin Carlson (Dec 08 2025 at 18:41):This looks great! Is the late Zoom link posting a one-time-only thing? It's a bit inconvenient to have a calendar item that just contains the instructions to navigate to a GitHub and poke around for a Zoom link, as opposed to having the link right in the event.
JS PL (he/him) (Dec 11 2025 at 23:44):Reminder about the first PCT talk by Richard Garner in a little over an hour at , here is the zoom link: https://kyoto-u-edu.zoom.us/j/82401794000?pwd=VjVmzVjmlgxhkdHES4xYeQBTpMzQkS.1 (also on the website https://pctseminar.github.io/) join us if you're interested!
JS PL (he/him) (Dec 11 2025 at 23:45):Kevin Carlson said:
This looks great! Is the late Zoom link posting a one-time-only thing? It's a bit inconvenient to have a calendar item that just contains the instructions to navigate to a GitHub and poke around for a Zoom link, as opposed to having the link right in the event.
Fair point : still ironing out the details and setup. Will bring it up with the others. Thanks!
Jack Jia (Dec 12 2025 at 00:19):How long are the talks? I can't find any information on the website.
JS PL (he/him) (Dec 12 2025 at 00:25):Jack Jia said:
How long are the talks? I can't find any information on the website.
45-60 minutes
JS PL (he/him) (Jan 11 2026 at 21:12):We also have a youtube channel where we will be posting the talks: https://www.youtube.com/channel/UCdHnpEqXvvvYw16Cg_L6O3g
JS PL (he/him) (Jan 12 2026 at 05:43):Taichi Uemura will give a talk for the second session of the PCT seminar
(<https://pctseminar.github.io/>) on Friday January 16 at 10am JST/12pm AED
(1am UTC).
The zoom link to join the seminar is here:
<https://kyoto-u-
edu.zoom.us/j/82401794000?pwd=VjVmzVjmlgxhkdHES4xYeQBTpMzQkS.1>
Title: A direct-categorical approach to opetopic sets and opetopes
Abstract: Opetopes and opetopic sets were introduced by Baez and Dolan as
a combinatorial approach to weak ω-categories. Since its birth,
several equivalent definitions have been proposed. Recently, Leclerc gave
a posetal definition of opetopes, where an opetope is encoded as a poset
of cells ordered by the subcell relation. This seems to be the most
elementary and simple definition of opetopes, but there is some
complication related to loops. In this talk, I propose another elementary
definition of opetopes, encoding an opetope as a direct category rather
than a poset. Loop issues are resolved by allowing distinct parallel
morphisms, and the theory of opetopic sets gets simplified.
We hope to see you there!
JS PL (he/him) (Jan 16 2026 at 00:07):Reminder about the second PCT talk by Taichi Uemura in a little under an hour at , here is the zoom link: https://kyoto-u-edu.zoom.us/j/82401794000?pwd=VjVmzVjmlgxhkdHES4xYeQBTpMzQkS.1 (also on the website https://pctseminar.github.io/) join us if you're interested!
JS PL (he/him) (Feb 24 2026 at 03:14):Yuki Imamura will give a talk for the third session of the PCT seminar (https://pctseminar.github.io/) on
The zoom link to join the seminar is here: https://kyoto-u-edu.zoom.us/j/82401794000?pwd=VjVmzVjmlgxhkdHES4xYeQBTpMzQkS.1
Title: A formal category theoretic approach to the homotopy theory of dg categories
Abstract: A dg category is a category enriched over the category of complexes of modules. Arising from the homotopy theory of complexes up to quasi-isomorphism, dg categories admit a natural homotopy theory in their own right, in which the weak equivalences are the quasi-equivalences. In this talk, I present an approach to the homotopy theory of dg categories from the viewpoint of formal category theory. Concretely, I construct a proarrow equipment in the sense of Wood that captures the homotopy theory of dg categories, and study the behavior of homotopy limits in dg categories within this framework.
We hope to see you there!