Sarkar, JyotirmoyRashid, Mamunur2023-09-072023-09-072022Sarkar J, Rashid M. Mathematical Musings on the External Anatomy of the Novel Corona Virus: Part 4: Models of n-Cov. Resonance. 2022;27(10):1719-1730. doi:10.1007/s12045-022-1466-3https://hdl.handle.net/1805/35464What is the shape of the novel coronavirus (n-CoV) which has turned our world upside down? Even though under a microscope, it looks dull, unattractive, and even disgusting, creative artists have attributed to it bright colors, made it look pretty, and depicted it as a thing of beauty. What can a mathematician contribute to this effort? We take a purist’s point of view by imposing on it a quasi-symmetry and then deriving some consequences. In an idealistic world, far removed from reality but still constrained by the rules of mathematics, anyone can enjoy this ethereal beauty of the mind’s creation, beckoning others to join in the pleasure. Our musings end with this Part 4. We fondly hope readers have benefited from our suggestion that they indulge in their own musings, tell others about them, and propagate the good virus of mathematical thinking.en-USPublisher PolicyGreat circlePlatonic solidsDualitySpherical geometryGirard’s theoremHamiltonian cycleIntermediate value theoremArticle