Harry Potter and the Methods of Rationality discussion thread, part 19, chapter 88-89

Vaniver

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 88-89. The previous thread has passed 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.

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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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.

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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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's not a fire vulnerability. It's just that chemical change stops the regen.

Just because burning cut troll flesh makes it not regen doesn't mean that it will penetrate. They're not highly flammable like Twilight/Luminosity vampires. If I was designing Muggle anti-troll weaponry, I'd be going for something to penetrate into the body and then spread incendiary material. Not a flamethrower. (Although first physically injuring trolls and then dousing them with napalm might work, sort of.

Incendio in the troll's eye would just burn out the eye.

Mana cost in HPMOR seems to affect cooldown more than castability of spells, and transfiguration seems to have no cooldown but (for Harry, Q and other powerful wizards are much faster) is time-consuming.

Harry should be able to near-instantaneously slice-and-dice any transfigurable object by using very thin cutting boundaries, and even cause explosive separation by using compressed inert gas, or even a friction-sensitive explosive (most explosives form fairly nonhazardous materials) Even if the acid failed to prevent the regen, he could have dismembered the troll temporarily and bought time to try something else or to burn it.

ETA: Also, Harry is now able to predict what forms of transfiguration are dangerous, and mild transfiguration sickness is not