Harry Potter and the Methods of Rationality discussion thread, part 26, chapter 97

palladias

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 97. The previous thread is at nearly 500 comments.

There is now 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.)

The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system.

Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25.

Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically:

You do not need to rot13 anything about HP:MoR or the original Harry Potter series unless you are posting insider information from Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).

If there is evidence for X in MOR and/or canon then it’s fine to post about X without rot13, even if you also have heard privately from Eliezer that X is true. But you should not post that “Eliezer said X is true” unless you use rot13.

The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system.

Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25.

Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically:

You do not need to rot13 anything about HP:MoR or the original Harry Potter series unless you are posting insider information from Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).

If there is evidence for X in MOR and/or canon then it’s fine to post about X without rot13, even if you also have heard privately from Eliezer that X is true. But you should not post that “Eliezer said X is true” unless you use rot13.

it turned out that sulfuric acid would freeze at just ten degrees Celsius

That does not appear to be correct. If http://science.howstuffworks.com/sulfuric-acid-info.htm is accurate, then frozen sulfuric acid ice cannot get much warmer than frozen water and the more usual concentrations freeze at much lower temperatures. However, high concentrations (98%, freezing at 3°C), while more expensive, are easily available online http://www.sciencecompany.com/Sulfuric-Acid-Concentrated-1L-P6550.aspx (plus it doesn't seem hard to concentrate yourself http://chemistry.about.com/od/makechemicalsyourself/a/How-To-Make-Sulfuric-Acid-At-Home.htm), so Harry could probably get a supply that would still work; he'd just have to keep it in ice, rather than merely keep it refrigerated.

Wikipedia claims 10°C, but it also says “Sulfuric acid in solution with water causes significant freezing-point depression of water's melting point”, which suggests that both Harry and HowStuffWorks are right. Harry is probably thinking of the pure acid.

(Also, that wouldn’t affect his plan. He only needs it solid so he can transfigure it, and the only significance of the freezing point is that it’s easily reachable, not exactly how high it is above 0°C.)