ELISABETH BUSSER
226 articles published in Tangente
History and CultureN°211Apr 21, 2023Drawing the Earth: a long history
Understanding the shape of the planet we live on, and then depicting it, has been an adventure since the earliest days of antiquity. At every stage, the model has been refined and improved, drawing ever closer to the one we use today: the geoid.
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Games and ChallengesN°211Apr 21, 2023Classifying knots
Knots can be combined to form new ones—or, conversely, simplified. We can borrow the vocabulary of number theory and classify them rather like the chemical elements. What varied and unexpected facets knot theory has!
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Math for everyoneN°210Feb 23, 2023Charles V's letter, readable at last
An encrypted letter from Charles V (1500–1558), Holy Roman Emperor, addressed in 1547 to Jean de Saint-Mauris, his ambassador to the king of France, and housed in the autograph collection of the Bibliothèque Stanislas in Nancy (Meurthe-et-Moselle), has just been not merely read but deciphered. Long passages in the letter are encoded.
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History and CultureN°210Feb 23, 2023When Euler gets it wrong
Even the greatest mathematicians sometimes make mistakes. It is only human! It even happened to one of mathematics’ legendary figures, the great Leonhard Euler, in connection with sums of powers.
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History and CultureN°85Feb 14, 2023On a banknote
Known as the "Pascal", this 500-franc note bearing the scholar's portrait had a long career: it remained legal tender from 1969 to 1997.
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History and CultureN°85Feb 14, 2023Celebrating Pascal's 400th anniversary in Clermont-Ferrand
In Auvergne, the city of Clermont-Ferrand, Clermont Auvergne Métropole and the University of Clermont Auvergne (UCA), together with their many partners, are preparing to celebrate the 400th anniversary of Blaise Pascal's birth in 2023.
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Math for everyoneN°209Dec 23, 2022The football World Cup's "8"
Despite its Möbius-strip appearance, the logo of the 2022 FIFA World Cup is simply an "8".
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Math for everyoneN°209Dec 22, 2022The golden ratio in sangaku
Though Western in origin, the golden ratio is said to be everywhere. So we went looking for it in sangaku… and struggled to find it, except in a few rare figures. But perhaps we simply overlooked it!
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Maths and philosophyN°84Nov 21, 2022Editorial
"Tangente", from the Latin tangere, "to touch". If it's the name of your favorite magazine, it is because the word is rich in meanings that have opened up entire branches of mathematics.
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Math for everyoneN°84Nov 21, 2022Constructing tangents
If we know how to carry out the classic straightedge-and-compass constructions, we are perhaps less at ease drawing the common tangents to two circles. Now is the time to put our whole range of knowledge of Euclidean geometry into practice!
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Math for everyoneN°84Nov 18, 2022When waves go off on a tangent
Whether reflecting sound or waves, parabolic reflectors rely on the properties of tangents to conic sections. Let's fully dissect the underlying geometric phenomenon exploited in the making of antennas of every kind.
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History and CultureN°208Oct 20, 2022In the classroom in the 1960s
In the 1960s curriculum, geometric transformations were studied in some depth. These included, of course, translations (covered in the French seconde, equivalent to tenth grade) and the group they formed.
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