But for researchers at the Massachusetts Institute of Technology? They see things quite differently, and they made this known in a study conducted — in all seriousness — in collaboration with the École polytechnique fédérale de Lausanne and published on 4 April. The study in question deals with the dynamics of coating curved surfaces — spheres, in this case — with a more or less viscous liquid, which may be a polymer, something that will appeal not to confectioners this time, but to manufacturers. By visualizing the flow of the precious liquid every two seconds and varying the size of the balls, they arrived at "the chocolate equation":
hf=μ0Rρgτc.h_f=\sqrt{\frac{\mu_0 R}{\rho g \tau_c}}.
Relax, it's not that complicated: *hf is the thickness of the chocolate shell, R its radius, μ0\mu_0 the viscosity of the chocolate, g* the acceleration due to gravity, and τc\tau_c the hardening time of the chocolate. The confectioner no longer has any excuse for ruining their pralines!