The Yellow Cake is the title of a paper by Andrzej Roslanowski and Saharon Shelah which appeared in Proceedings of the American Mathematical Society in 1998. It is curious in that apparently no-one in the mathematical community has any idea what the term "yellow cake" refers to, and it's not explained, or even mentioned, in the paper itself!

Mathematical research papers are not noted for being easily comprehensible by the general public. The greek symbols, strange shapes and meagre explanation make deciphering the language hard enough, and that's before you even try to understand the complex concepts they describe. However, The Yellow Cake goes beyond obfuscated. It consists of baffling propositions and definitions, followed by absolutely bewildering "proofs", that I'm not sure are even related to the things they are supposed to be an explanation of.

To dismiss The Yellow Cake as nonsense off-hand would not be right, however. All the referenced papers exist, and unfortunately take the same sort of form as The Yellow Cake itself. The real puzzle is what is the yellow cake? Apparently, no mathematicians have ever heard of it, a search for "yellow cake" and any of the terms that would accompany it in a technical paper return only the original paper itself; surely if such an unconventional term was being used, it deserves an explanation? Or at least a mention?

There are certain phrases and clues inside The Yellow Cake that hint at the paper being a clever joke, such as notions being "sweet-forcing", sets being "spread" and segments being "proper" or not, but would the authors do such a thing? Both of them are legitimate researchers at American and European institutions, plus the paper was presented in a reputable publication. Could the two researchers be relying on the "emperor's new clothes" effect, hoping that no-one would admit to not understanding the paper, either in academia or at the Proceedings of the American Mathematical Society, so that their ruse passed through unnoticed? The entire paper could be testing the behaviour and integrity of the mathematical community, or it could be trying to show how specialised their field (whatever it is) has become, so that an adventurous paper can no longer be differentiated from nonsense. Then again, maybe yellow cake is some sort of "in joke", known only to a few researchers, and inserted as the title of a valid paper for want of anything better.

To adequately answer all these questions would probably involve performing in excess of 10 years of mathematical research to satisfactorily convince yourself that this paper was genuine or otherwise. However, I am happy to leave it an open question, and potentially witness the birth of a new form of comedy.

Footnote: When first hearing about this story, I was convinced that the name of the paper was taken from the UK comedy show, BrassEye. In all, seven episodes were shown, and one of them, called "Drugs", pretended that a new, highly addictive, highly dangerous stimulant was sweeping into the country from Eastern Europe. Many famous people were convinced by this joke, including David Amess, an MP who actually raised a question on the subject in the House of Commons1. This new drug was called cake, and just happened to be yellow in colour; coincidence or not? Originally, I thought so, because I was led to believe that BrassEye was first screened in 2001. However, thanks to lj, it turns out BrassEye was originally aired in 1997, making it perfectly possible, if not particularly likely, that the authors were inspired to name their spoof paper after the spoof TV show.

shows the actual question (and response!) that David Amess produced. Thanks again to lj for the correction and link.

Education Guardian -
The Yellow Cake - RoSh:686 1998-06-23


18 Feb 04

I decided to settle this matter and emailed one of the authors, Andrzej Roslanowski. It turns out he was puzzled by all the fuss over his paper, as the term "yellow cake" is established in the history set theory. Although this does cast some doubt upon the completeness of the research performed for the newspaper article, as well as my own, this situation does present an interesting phenomenon. Why is the public so willing to rubbish ideas they don't understand, in a sort of inverse emperor's new clothes effect. However, this writeup is not the place to discuss the deeper meanings of the town and gown conflict.