Science Focus (issue 26)

with high sodium content, salami may exacerbate health risks and conditions relating to the heart and kidneys [1, 3]. As all uncooked meats do, salami too poses risks of Salmonella infection and trichinellosis (a disease caused by infection with Trichinella parasites). Kittens and pregnant cats should not be fed salami, as their immune systems are vulnerable to toxins and bacteria [3]. Are They Really Liquid Enough to “Sits” Where They “Fits”? We often ponder over unusual, inconsequential ideas and their meanings. Often, scientists are among those people pondering these questions. If you have ever wondered whether cats are truly liquid as you see yet another cat weasel its way into narrow crevices and hilariously small containers, you’re in luck. Researcher Marc-Antoine Fardin is one such scientist, who was awarded the Ig Nobel Prize in Physics (footnote 2) for answering this absurd question. Using rheology, the study of deformations and flows of matter, he found that, under certain conditions, cats may fit the definition of a liquid [4]. To determine the state of a material over a given time frame, rheologists look at the relationship between two time periods: the relaxation time and the experimental time. Aptly named, the relaxation time is the time taken by a material to modify its form to fit in a container; in this case, it would be the time taken by a cat to “fits” where it “sits”. Experimental time refers to the time elapsed since the deformation is observed; in this case, this could be the time the cat is observed since it first puts its paws in to “sits” in the fruit bowl. Finally, rheologists look at the ratio between the relaxation time and the experimental time — the Deborah number De: (where tc is the relaxation time and tp is the experimental time) When the Deborah number is less than 1, i.e. tp > tc, the material is considered relatively liquid. If you think carefully, by this definition, whether a material is perceived to be liquid or solid all depends on whether you observe it long enough for the deformation to take place. As Fardin puts it, “If you take a timelapse of a glacier on several years you will unmistakably see it flow down the mountain [5].” Similarly, a 7

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