# Lumifer comments on Harry Potter and the Methods of Rationality discussion thread, March 2015, chapter 119 - Less Wrong

4 10 March 2015 06:10PM

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Comment author: 10 March 2015 06:57:12PM *  6 points [-]

Hopefully the apparent time limit on the Philosopher's Stone isn't going to get worse over time.

Good point. A time limit of 3:54 does seem too arbitrary to be hard-coded.

Harry also hasn't considered that it may only be good for some finite number of permanent transfigurations. He's going to try to use it many more times than it probably has been used in a very long time.

At least he only intends to use the Stone as a stop-gap measure for fighting death until he is able to properly end the world.

[edited]

Comment author: 10 March 2015 07:40:31PM 3 points [-]

A time limit of 3:54 does seem too arbitrary to be hard-coded

X to 1 stellar day as 366.24 stellar days to 1 mean year.

X = 235 seconds, 3:55.

Almost.

Comment author: 10 March 2015 08:03:01PM *  0 points [-]

The more natural 365.24 is even worse.

We really want something like 370. That takes us back to the late Cretaceous, and I don't think that EY wants to push things that far back.

Comment author: 10 March 2015 11:18:36PM *  -1 points [-]

Another close figure: The sidereal day is 3 minutes, 56 seconds shorter than the solar day. If the solar day has a negative leap second, the difference is 3'55".

Comment author: 11 March 2015 01:49:11AM 0 points [-]

I do not know what some terms mean, but I think that is not another close figure, that is the same figure.

Comment author: 11 March 2015 03:45:48AM -1 points [-]

I mean, close to 3'54".

Comment author: 11 March 2015 04:21:21AM 0 points [-]

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.

Comment author: 11 March 2015 05:02:31AM *  -1 points [-]

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.

Comment author: 11 March 2015 03:26:46PM 1 point [-]

Yes, and my claim is that that is what you did too without knowing it. Think about what sidereal and solar day mean, and how you would calculate one from the other.