ABSTRACT
“Back-of-the-envelope calculation” is very popular among chemists or physicists. Amidst discussions in pubs, bars, cafeterias or restaurants, they would use any piece of paper that they can find, such as the back of used envelopes, for drawing chemical mechanisms, making short calculations, or testing assumptions. The “questions of the day” were named “exercises”, then “joggings”, but the topic remained the same: because many students of the research group love cooking and science, they generally discuss questions of chemistry and physics with a relationship with cooking. Certainly, some students prefer experiments, and other students prefer theory. The current appeal of cooking, with TV shows, online recipes, podcasts, etc. has rendered molecular and physical gastronomy fashionable. There is a difference between a law, in the sense of the civil community, and an equation that describes a set of experimental data, even if this equation then predicts the result of particular experiments that have not been done.
