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John Baez (Dec 10 2020 at 22:28):This new blog article of mine:
John Baez (Dec 10 2020 at 22:29):explains the J-homomorphism and says a bit about how it's used to understand the stable homotopy groups of spheres. And, it states an amazing theorem by Frank Adams relating stable homotopy groups of spheres to Bernoulli numbers!
John Baez (Dec 10 2020 at 22:30):It also announces something exciting that I'm gonna do next year.
Matteo Capucci (he/him) (Dec 10 2020 at 23:06):Neat and fascinating article John, as always! The link between homotopy groups of spheres and sphere packings is intriguing, to use an euphemism. Is it something know?
Matteo Capucci (he/him) (Dec 10 2020 at 23:07):John Baez said:
It also announces something exciting that I'm gonna do next year.
Also, good luck with this big step! Are you just done with teaching or does this include supervising PhD students as well?
John Baez (Dec 11 2020 at 00:06):Thanks! I'm not taking PhD students now, and in fact I quit taking new ones a few years ago, when I had seven of them! After my two remaining students - @Christian Williams and @Jade Master - are done, I may take more. But I want to see what life without grad students is like. Having grad students is like driving a train: it takes time to build up speed, then you can do impressive things, but you can't make sharp turns in your research.
John Baez (Dec 11 2020 at 00:07):The link between homotopy groups of spheres and sphere packings is intriguing, to use an euphemism. Is it something know?
John Baez (Dec 11 2020 at 00:08):I'd never heard anyone make this observation before. Maybe the people who were smart enough to observe it were also smart enough not to mention it.
Reid Barton (Dec 11 2020 at 00:16):John Baez said:
It also announces something exciting that I'm gonna do next year.
Going outside?
Reid Barton (Dec 11 2020 at 00:16):Looking forward to the future posts, I've always wanted to learn about this connection as well.
John Baez (Dec 11 2020 at 00:18):Heh, I go outside for an hour-long walk every day.
Tobias Fritz (Dec 11 2020 at 08:26):What exciting news! UCR will be losing an outstanding teacher, but we will be gaining even more of a brilliant expositor and mathematical visionary.
Tobias Fritz (Dec 11 2020 at 08:32):I'm sure that it'll be a lot of fun. Do you think you'll be missing teaching as well?
John Baez (Dec 11 2020 at 15:48):Thanks, Tobias!
Right now I'm really looking forward to not teaching. Teaching is fun but I've been doing it for 30 years - other things are fun too. I really want to be left alone to think and write. I'm dreading how this spring I'll need to teach a large calculus class over Zoom... and then, thank god, it will be over.
John Baez (Dec 11 2020 at 15:49):If I miss teaching, I'm pretty sure UCR will let me teach math grad courses on whatever I want... for no pay. That might be fun if I'm writing a book about something.
If Brendan and David's Topos Institute takes off, I plan to work and teach there a bit.
John Baez (Dec 11 2020 at 15:50):I've also considered teaching classes on YouTube. That could also be fun - like, writing a book on some subject and giving YouTube lectures on that subject to help figure out how to explain it.