Since Mastodon saw its initial popularity circa 2017, I've noticed that most users and those reporting on it either don't think about the Fediverse as anything more than Mastodon, or treat its history as beginning with Eugen Rochko and the beginning of Mastodon. In fact, Mastodon is the latest in a long line of federated social networks going at least back to Identi.ca, and though I wasn't around for all of it, I find this history pretty interesting. (Thread; boosts welcome!)
Joyal invented the concept of a 'species' to formalize the idea of a structure that we can put on finite sets. A lot of combinatorics is about species! There's a species of partitions, a species of simple graphs, a species of 2-colorings, etc.:
I'd like to talk about two species today: linear orderings and permutations. There are n! linear orderings of an n-element set, and also n! permutations. But they are not isomorphic as species!
Today is #TransDayofRemembrance when we honor and remember trans lives taken by violence. How horrifying that a deadly attack upon the LGBTQ+ community in Colorado Springs should occur right before this solemn day.
Hate isn’t born in us. It is taught. It must end.
This starts with our political leaders, who must cease their cynical attacks against our community before another attack occurs.
Call out the hate. Remind them of its consequences. Hold them to account.
Programming languages / compilers / performance / logic /categories nerd. With a speckling of other interests.
All opinions my own.
A Mastodon instance for programming language theorists and mathematicians. Or just anyone who wants to hang out.