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Showing results for tags 'conservation'.
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I've been thinking about the physics and realmatics of soulcasting. We have seen quite a bit of it on screen, but there are, of course, still mysteries. Going down the soulcasting rabbit-hole, I came across the following WoB: https://wob.coppermind.net/events/105-17th-shard-forum-qa/#e1139 Unfortunately, this seems to disagree with the canonical description of soulcasting. I imagine Brandon said this because in general he likes to preserve the laws of physics. (In this case the conservation of mass.) But how does mass conserving soulcasting contradict canonical soulcasting: 1) Soulcasting is shape preserving. We have seen this in every case where it is possible to see the shape of both the original object and the soulcast object. However, not only is it shape preserving, soulcasting also seems to be volume preserving. We have never seen a soulcast object, when soulcast into a denser material, shrink. This would be a very visible effect. It looks like marble has a density of about 2.7 g/mL. A human body has a density(if we include the air filled lungs) a little less than water, so let's call it 1 g/mL. If soulcasting conserved mass, a body soulcast to marble would shrink in volume by about 63%. This would cause a 6 ft. man to become a 4' 4" statue. 2) If soulcasting conserved mass, soulcasting to a lighter density material would cause catatrophic explosions. The analysis would be easier if she had soulcast it to air, but let us consider the example of Jasnah soulcasting the boulder to smoke. The smoke floated upward so it is less dense than the surrounding air. It looks like air at Standard temperature and pressure is about 1.3e-3 g/mL. If the boulder was 1m diameter sphere (This is being generous, it was likely much larger), it would have a mass of about 1.4 million grams of 1400 kg (using the density of marble as above). If soulcasting conserved mass, this would result in smoke that really wants to occupy about 1 million liters. To put that in D&D terms, that is 307 5ftx5ftx5ft cubes. Upon being soulcast the smoke would initially be at a pressure of 770 atms. A rough estimate would put the resulting expansion of the smoke at the equivalent of 55 lbs of TNT. (This last figure is very detail dependent and it is possible that I made some mistakes in the calculation. To make the conversion to equivalent pounds of TNT, I referenced http://ftp.feq.ufu.br/Luis_Claudio/Segurança/Safety/GUIDELINES_Chemical_Process_Quantitative_Risk_Analysis/0720X_02e.pdf) My conclusion? Soulcasting doesn't preserve mass, it preserves volume. Breaking conservation of mass is always problematic if you want to have physics behave in any way like we are used to, but I have some realmatic thoughts about that that I will share soon. I think that you can avoid the troubles associated with non-conservation of mass in a realmatic way.
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