Archives de catégorie : English

Posts in English.

What is the way of packing oranges? — Kepler’s conjecture on the packing of spheres

Originating author is Christiane Rousseau. What is the densest packing of spheres? Kepler conjectured that it was the one you observe with oranges at the fruit shop, and which is called the face-centered cubic lattice (Figure 1). At the International … Continuer la lecture

Publié dans Mathematics Within the Last 100 Years | Un commentaire

Higher Dimensions

Originating authors are Markus Ruppert and Hans-Georg Weigand. 1. Looking for the next dimension Does our world really have more than three dimensions? If so, do objects in higher dimension have a relation to the world around us? Is it … Continuer la lecture

Publié dans Mathematics Within the Last 100 Years | 3 commentaires

Benford’s law: learning to fraud or to detect frauds?

Originating author is Christiane Rousseau. It is very risky to change too many numbers in some fi nancial statements if one does not know some mathematics. Indeed, most often the numbers appearing in fi nancial statements follow some strange mathematical rule, called … Continuer la lecture

Publié dans Mathematics Within the Last 100 Years | 2 commentaires

Map colouring and Gröbner Bases

Originating author is Marcelo Escudeiro Hernandes. By the famous “Four Colour Theorem”, only four colours we need to colour a map so that no bordering regions have the same colour. Using polynomial equations and Gröbner bases we can determine if … Continuer la lecture

Publié dans Mathematics Within the Last 100 Years | 3 commentaires

Symmetry Step by Step

Originating author is Ana Cannas da Silva. Symmetry has always fascinated and served humankind in architecture, arts, engineering and science. Over thousands of years symmetric patterns have been used to create fabrics, baskets, floors, wallpapers and wrapping papers, and so … Continuer la lecture

Publié dans Mathematics Within the Last 100 Years | 2 commentaires

Recurrence and induction

Originating authors are Michèle Artigue and Ferdinando Arzarello. Given a square grid, it is easy to draw squares whose vertices are intersections of the grid lines. But is it possible to do so for other regular polygons, for instance an … Continuer la lecture

Publié dans Mathematics Within the Last 100 Years | 3 commentaires

Mathematicians’s Delight

December’s Book of the Month is Mathematician’s Delight by W. W. Sawyer, Dover Publications 2007 (originally Penguin Books, 1943). This is Sawyer’s first book, and was written with the aim “to dispel the fear of mathematics.” According to the W. … Continuer la lecture

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Math Here and Now

December’s Site of the Month: Math Here and Now This is one of the High School resource pages of the National Council of Teachers of Mathematics. It contains up to date instances of mathematics in our world. Each example has … Continuer la lecture

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Mathematical Association of America

November’s Site of the Month: Mathematical Association of America A comprehensive site aimed primarily at the undergraduate level, but useful for all those interested in mathematics. At the bottom of the page the Community Centre is worth exploring: the SIGMAA’s … Continuer la lecture

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Gödel, Escher, Bach – An Eternal Golden Braid

November’s Book of the Month is Gödel, Escher, Bach: An Eternal Golden Braid by Douglas R. Hofstadter (Basic Books, 1979). This book is about symmetry, self-reference, and other fundamental mathematical ideas explored through the works of the three people named … Continuer la lecture

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