Arnd Leike of the University of Munich was awarded the 2002 Ig Noble Physics prize for demonstrating that beer froth obeys the mathematical Law of Exponential Decay. [Reference “Demonstration of the Exponential Decay Law Using Beer Froth,” Arnd Leike, European Journal of Physics, vol. 23, January 2002, pp. 21-26.]
Since then, investigations into the decay of beer froth have continued – and one experimental research project in particular has challenged the idea that it decays exponentially. A team from the Institut für Angewandte und Physikalische Chemie–Arbeitsgruppe Chemische Synergetik, Universität Bremen, Germany, “call in question the results presented by Leike”, saying that :
It is our finding that the foam volume does not shrink simple exponentially but in terms of higher order according to the equation lnV(t) = a−bt −ct2.5 (3.1). The term ct2.5 describes the reorganisation of the bubble arrangements which will lead to an Apollonian gasket of bubbles. [our emphasis]”
See: The Apollonian decay of beer foam bubble size distribution and the lattices of Young diagrams and their correlated mixing functions
in Discrete Dynamics in Nature and Society, Volume 2006, pp. 1–35, by S. SAUERBREI, E. C. Haß, AND P. J. PLATH.