### Seminar on This Week’s Finds

#### Posted by John Baez

I wrote 300 issues of a column called *This Week’s Finds*, where I explained math and physics. In the fall of 2022 I gave ten talks based on these columns. I just finished giving eight more! Now I’m done.

Here you can find videos of these talks, and some lecture notes:

Topics include Young diagrams and the representation theory of classical groups, Dynkin diagrams and the classification of simple Lie groups, quaternions and octonions, the threefold way, the periodic table of $n$-categories, the 3-strand braid group, combinatorial species, and categorifying the harmonic oscillator.

If my website dies, maybe these lectures will still survive on my YouTube playlist.

Posted at December 1, 2023 4:01 PM UTC