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September 16, 2022

Young Diagrams and Classical Groups

Posted by John Baez

Young diagrams can be used to classify an enormous number of things. My first one or two This Week’s Finds seminars will be on Young diagrams and classical groups. Here are some lecture notes:

• Young diagrams and classical groups.

I probably won’t cover all this material in the seminar. The most important part is the stuff up to and including the classification of irreducible representations of the “classical monoid” End(ℂ n)\mathrm{End}(\mathbb{C}^n). (People don’t talk about classical monoids, but they should.)

Just as a reminder: my talks will be on Thursdays at 3:00 pm UK time in Room 6206 of the James Clerk Maxwell Building at the University of Edinburgh. The first will be on September 22nd, and the last on December 1st.

If you’re actually in town, there’s a tea on the fifth floor that starts 15 minutes before my talk. If you’re not, you can attend on Zoom:

https://ed-ac-uk.zoom.us/j/82270325098
Meeting ID: 822 7032 5098
Passcode: XXXXXX36

Here the X’s stand for the name of a famous lemma in category theory.

Continue reading “Young Diagrams and Classical Groups” …
Posted at 5:49 PM UTC | Permalink | Followups (9)

September 12, 2022

The Algebra of Grand Unified Theories

Posted by John Baez

Fans of the nn-Category Café might like The Cartesian Café, where Timothy Nguyen has long, detailed conversations with mathematicians. We recently talked about the fascinating mathematical patterns in the Standard Model that led people to invent grand unified theories:

For more details, go here:

Posted at 11:27 PM UTC | Permalink | Followups (1)

September 11, 2022

Seminar on This Week’s Finds

Posted by John Baez

Here’s something new: I’m living in Edinburgh until January! I’ll be working with Tom Leinster at the University of Edinburgh, supported by a Leverhulme Fellowship.

One fun thing I’ll be doing is running seminars on some topics from my column This Week’s Finds. They’ll take place on Thursdays at 3:00 pm UK time in Room 6206 of James Clerk Maxwell Building, home of the Department of Mathematics. The first will be on September 22nd, and the last on December 1st.

We’re planning to

1) make the talks hybrid on Zoom so that people can participate online:

https://ed-ac-uk.zoom.us/j/82270325098
Meeting ID: 822 7032 5098
Passcode: XXXXXX36

Here the X’s stand for the name of a famous lemma in category theory.

2) record them and eventually make them publicly available on my YouTube channel.

3) have a Zulip channel on the Category Theory Community Server dedicated to discussion of the seminars: it’s here.

More details soon!

I have the topics planned out….

Continue reading “Seminar on This Week’s Finds” …
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