Harry Potter and the Methods of Rationality discussion thread, February 2015, chapters 105-107

b_sen

Two new short chapters! Since the next one is coming tomorrow and we know it'll be short, let's use one thread for both.

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 105 (and chapter 106, once it comes out tomorrow). EDIT: based on Alsadius' comment about thread creation for MOR chapters, let's also use this thread for chapter 107 (and future chapters until this nears 500 comments) unless someone objects to doing so. Given that this is the final arc we're talking about, thread titles should be updated to indicate chapters covered.

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.)

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Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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

Two new short chapters! Since the next one is coming tomorrow and we know it'll be short, let's use one thread for both.

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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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 Defense Professor sent Harry the forged message after 11:04pm, but early enough that Harry was able to arrive at 6:49 with 1 hour left on his time turner. The time-turner has been confiscated, but this is still a big security hole.

Example possibility: Harry and Quirrel arrive at the mirror, and time-turned Harry is already there with Dumbledore, Moody, Madam Bones and a dementor, which had not been detected by present Harry because patronus 2.0 is out and shielding everyone from it. Quirrel can't apparate away in Hogwarts, patronus 2.0 stops any AK, and Dumbledore & friends can hold Voldemort off long enough for the dementor to start sucking face with Voldemort, who is particularly vulnerable. Harry retrieves his time-turner and goes back an hour to message Dumbledore via patronus and set this ambush up. Asking Harry to state whether he has betrayed him is of limited use here, since the betrayal can happen in the future but impact the present.

Why has The Defense Professor deliberately preserved an hour on Harry's time-turner? It must be significant to his plan.

I noticed that as well. However, at Azkahban QQ reserved an extra use of the time turner for the end and it proved necessary. He may just think that as a best practice for plotting one should leave an extra use of time turners in as margin of safety.

10alephphi11y

That's been bothering me ever since chapter 104 came out. It doesn't seem likely that Quirrel would have just missed that, so I see a couple possibilities: 1) Part of Quirrel's plan somehow requires Harry to use the time turner once, so by having Harry go back five hours he limits Harry's use of it as much as possible. 2) It's a trap. Leaving via time turner is an excellent escape mechanism, and Quirrel knows that Harry has a tendency to overuse it for that purpose. So if Harry does manage to do something unexpected, Quirrel's hoping he'll go for the time turner--only to find that it doesn't work. Why doesn't it work? Because Quirrel wrote the note at 12:04, went back via his own time turner, and handed the note to the anonymous Hufflepuff*. Thus, if Harry were to activate his time turner for the sixth time at 7:00, it would fail in some fashion ("for you couldn't send information further back in time than six hours, not through any chain of Time-Turners" -- chapter 61). This is a pretty narrow window, though. Quirrel would have to anticipate that Harry might immediately go back from 11:04 to 6:04 once he got the message, so Quirrel wouldn't have written the note any later than 12:04 (if he wrote it at 12:20, for example, and Harry tried to go back to 6:04, it would fail and he'd know something was up.) Which means that the forbidden period can't end any later than 6:04, and the absolute earliest Harry would want to use the sixth turn would be 6:49 when the whole thing started. So there's a 15 minute period from 6:49 to 7:04 where Harry thinks he can use the time turner but can't. This would be fine if the whole process were to finish in 15 minutes, but that seems unlikely, especially with Quirrel dawdling in chapter 107. *It's amusing to think that Quirrel went back to 11:04 to hand the note to the Hufflepuff, whose quote "I know you said not to talk to you, but -" would have, if he had not been interrupted by Harry, ended something like "but I don't see why