If the sidereal day and the solar day mean what I am guessing they mean, your 3:55 and Lumifer's 3:55 come from the same place.
No, what he did was divide the sidereal day by 366,24 and got 235 seconds, so there would be as many Stone's periods in a day as there are days in a year.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 119.
Plans for next chapter release:
There is a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)