Finally wrote up the last two parts of my answer the question "Why can’t you fall into a white hole?" Took me two or three weeks to figure it out, given that there is basically nothing about it in the literature. Not that I could find, anyway. Comments welcome.
This is the public group instrumental rationality diary for March 1-15.
Thanks to cata for starting the Group Rationality Diary posts, and to commenters for participating.
Next diary: March 16-31
Immediate past diary: January 16-31
Rationality diaries archive