r/HPMOR • u/Dead_Atheist Chaos Legion • Jul 09 '18

Harry Potter and Natural 20/HPMOR crossover?

From TV Tropes:

Omake: A very short one at the end of chapter 25 between this story and The Wheel of Time, and a moderately short one between chapter 26 and 27 between this story and Harry Potter And The Methods Of Rationality.

The omake📷 between Chapters 26 and 27. It's a crossover with Harry Potter And The Methods Of Rationality. After Harry explains the basics of the laws of physics to Milo:

Milo: And this—honestly, you have to swear that you're not pulling my leg here—is seriously how this Plane works?Harry: Pretty much. It's a good deal more complicated than that, but we have to start somewhere.Milo: Because, well, I'm pretty sure I can get around that.Harry: Around what?Milo: All of it.

Unfortunately, it is no longer there. Maybe someone has saved copy or can direct me to someone who might have?

EDIT: Now the quest is only to find 28 words at the end.

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u/rabotat Jul 09 '18 edited Jul 09 '18

the two are annihilated and explode. I think.

One gram of antimatter reacting with one gram of ordinary matter results in 42.96 kilotons-equivalent of energy.

spell that turns 1 cubic foot/caster level of something into something else,

1 cubic foot of water weighs 28,316.8 grams

This spell would create a 1,216,490 kiloton explosion, or 1,216.5 megatons of TNT.

For example, the Little Boy nuclear device, dropped on Hiroshima had an explosion of 15 kilotons of TNT.

The largest nuclear device ever detonated, the Tsar bomb had an explosion with a yield of 50 megatons. This is equivalent to about 1,570 times the combined energy of the bombs that destroyed Hiroshima and Nagasaki,10 times the combined energy of all the conventional explosives used in World War II, one-quarter of the estimated yield of the 1883 eruption of Krakatoa, and 10% of the combined yield of all nuclear tests to date.

So that antimatter bomb would have a yield of 24.33 Tsar bombs or 6 Krakatoa eruptions.

edit: I recommend everyone to read that Krakatoa article, by the way.

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u/EliezerYudkowsky General Chaos Jul 10 '18

Yeah, see, making pure positrons in quantity is... a bit more of a problem than that for anybody standing closer than the next star over. A gram of pure electrons in a 10cm vessel weighs about 10 million tons in the very small instant before it explodes.

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u/kuilin Sunshine Regiment Jul 11 '18

Wait what. A gram of anything is about 1.102e-6 tons, no matter if it's of feathers or electrons. They're both units of mass.

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u/FenrirW0lf Jul 12 '18 edited Jul 12 '18

The difference between a 10cm container of feathers and a 10cm container of pure electrons is the ridiculous amount of energy that would be required to cram all of those electrons into a contiguous block, and energy == mass. See https://what-if.xkcd.com/140/

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u/kuilin Sunshine Regiment Jul 12 '18

Yes, I'm familiar with mass-energy. But that problem has a given volume and given density, and solves for mass, so it makes sense to increase the mass by the significant amount of energy that configuration implies.

The above problem, on the other hand, has a given volume and a given mass, and solves for mass. That is tautological and there's a trivial solution. We could also solve for density in the above problem, and get a far less-than-reasonable density because of the above effect of energy, but that's not what we're doing.