Thursday, August 30, 2012

"Sticky physics of joy: On the dissolution of spherical candies"

Anyone reading this blog for any considerable period of time would know that I love reading or solving "mundane" problems. This one might barely qualify as one, I think. The authors are studying the "dissolution" of spherical-shaped candies.

Abstract: Assuming a constant mass-decrease per unit-surface and -time we provide a very simplistic model for the dissolution process of spherical candies. The aim is to investigate the quantitative behavior of the dissolution process throughout the act of eating the candy. In our model we do not take any microscopic mechanism of the dissolution process into account, but rather provide an estimate which is based on easy-to-follow calculations. Having obtained a description based on this calculation, we confirm the assumed behavior by providing experimental data of the dissolution process. Besides a deviation from our prediction caused by the production process of the candies below a diameter of 2 mm, we find good agreement with our model-based expectations. Serious questions on the optimal strategy of enjoying a candy will be addressed, like whether it is wise to split the candy by breaking it with the teeth or not.

In any case, I have to admit that I was snickering almost throughout the entire paper, especially the conclusion.

Finally we would like to address the question proposed in the very beginning of this study: What is the best strategy of eating such a candy? As so often, the answer depends on what the person enjoying the candy considers as the optimum. If the time the candy lives should be maximized, the eater of the candy should try to maintain the spherical shape of the candy by all costs. Since the e ect of mass transfer is driven by the surface, and the sphere possesses the smallest surface for a given volume among all possible shapes [5], any deviation of the spherical shape increases the process of losing mass. In particular, breaking the candy with the teeth enlarges the surface by a huge amount, making the candy vanish faster. Thus, from this point of view one should carefully try to keep the candy as spherical as possible. But there is another way to look at it: Suppose you break the candy with your teeth in many pieces. The surface becomes big, and in an instant the mass that is transferred away from the fragments becomes huge as well. This might amplify the effect of tastiness and joy, even though the life-time of the candy has become considerably short in this approach. Even though we now know how candies dissolve in time we stress that the best thing to do when eating a candy is to forget about these considerations, since they draw your attention away from what candies are made for: enjoyment.
C'mon, now. How could you not giggle when reading something like that in a physics paper? I'm only human! :)

I wouldn't be surprised if this gets nominated or even win the Ig Nobel Prize.


1 comment:

Blaise Pascal said...

It appears that this is the right paper (or at least, the right researchers) to answer the important question in this field:

How many licks does it take to get to the Tootsie Roll center of a Tootsie Pop?

Previous published experimental trials yielded an answer of 3 (W. Owl, 1970), but I believe the experimental protocol was flawed.