EA = Effective Altruism. Sam Bankman Fried identified with this group. Loosely associated with the rationalist movement.
Rationalists = Oh man where do I even start. A lot of them believe in the inevitable rise of an AI god who will rule us with either an iron or benevolent fist depending on how good a job we do of raising it. Also there’s a lot of misuse of Bayes’ Theorem for some reason.