Fairy-tale physics, plus laying the ‘cheese-eating surrender monkey’ meme to rest and putting a bit heavy tombstone on it so it won’t crawl outMay 7th, 2009 by Reinder
Chad Orzel at Uncertain Principles has started what looks like a series of posts on the physics of fairy tales. The first one, The Faulty Thermodynamics of Children's Stories, discusses the bowls of porridge in Goldilocks and the Three Bears:
After all, the Papa Bear, being the biggest, presumably has the largest bowl of porridge. Here, the story fits what we know about thermodynamics, as the largest bowl should take the longest time to cool, and thus should be the hottest at any time before the porridge bowls reach thermal equilibrium with their environment.
The description provided of the other two bowls, though, is not consistent with known physics. The Mama Bear, as the other adult, ought to have the second-largest bowl of porridge, which, in turn, ought to be the second-warmest bowl of porridge (assuming that equilibrium has not been reached). But the story says that this bowl is too cold! Meanwhile, the Baby Bear, who ought to have the smallest portion of porridge, has a bowl that is "just right," neither too not nor too cold. As the smallest bowl, though, the Baby Bear's porridge ought to be the coldest of the three (until equilibrium is reached, of course). There is no way for the bowls as described to have the temperatures described, while being consistent with the known laws of thermodynamics.
The only way that the story can make sense is if, for some reason, the Mama Bear has the smallest portion of porridge. In which case, this is a story with a very different moral than the original-- it's a story about the oppression of the Mama Bear, either because the patriarchy is forcing her to eat only the scraps left behind after her husband and child have had their fill, or because the unhealthy woodland media culture has saddled her with a negative body image, leading to an eating disorder.
and several dozen commenters fall over one another to deliver alternative explanations for this thermodynamical conundrum and challenging the underlying assumptions that the bowls were identical apart from their dimensions or that the three servings of porridge were served at the same temperature to begin with. I love this literal-minded kind of stuff. Show me a website that demonstrates empirically exactly how useless a chocolate teapot is, and I'm a happy nerd.
Prof. Orzel has already followed up with Fairy-Tale Physics 2: Spinning Gold which is about the nuclear physics of Rumpelstiltskin. Meanwhile, fellow Scienceblogger Matt Springer of Built on Facts has followed Prof. Orzel's lead and disusses The Physics of Rapunzel, specifically how much the mechanical problems of dropping that much hair down and bearing the weight of the Prince on it.
Elsewhere, and on a completely different subject, Robert Farley at Lawyers, Guns and Money has finally taken the time to write the post I've needed for years, one in which the stereotype of the French as having a cowardly military is examined and debunked. Actually, most of the debunking is done by the commenters - there's some excellent historical debate in that there post. So read both the post and the comments, pretty much all of them.