Jean-Jacques Dupas
107 articles published in Tangente
History and CultureN°88Nov 21, 2023Before black holes: hidden stars
In astronomy, a "black hole" is neither a hole nor black. The existence of these celestial objects was predicted by Einstein's theory of general relativity in the early twentieth century. It was demonstrated several decades later through the detection of gravitational waves produced by the coalescence of objects that came to be called black holes. What exactly are they?
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History and CultureN°214Oct 17, 2023Rhombi filling space
Are there polyhedra whose faces are all rhombi? Various mathematicians have studied this problem in solid geometry since the 17th century, each contributing to what is now a complete classification of the convex polyhedra.
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History and CultureN°214Oct 13, 2023Newton's method
Do you know how your calculator—or your smartphone's calculator—computes the square root of a number a > 0?
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History and CultureN°210Feb 23, 2023Ada Lovelace in the spotlight
Every year, on the second Tuesday in October, an event celebrates women innovators in computing. In 2022, a postage stamp bearing Ada Lovelace's likeness was issued.
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History and CultureN°85Feb 20, 2023The man who was not afraid of the void
In the 17th century, following the Ancients, it was held that "nature abhors a vacuum." By restoring physical experimentation to the heart of scientific inquiry, French scholars of the period would thoroughly reassess this claim. Pascal would devise an ingenious apparatus for "creating a vacuum."
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History and CultureN°85Feb 20, 2023The birth of the Pascal language
The Pascal programming language was specified in 1968 and designed in the 1970s by Niklaus Wirth (born 1934) at the Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland.
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History and CultureN°85Feb 20, 2023The secrets of the Pascaline
Electronic calculators, now built into our phones, have made us forget the mechanical marvels that came before them. At just 19, Blaise Pascal developed the first calculating machine and, after a hard struggle to perfect his invention, captivated his contemporaries.
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History and CultureN°85Feb 14, 2023All the way into space!
Astronomy has paid tribute to Pascal twice.
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Math for everyoneN°84Nov 21, 2022The revenge of the tangent spheres
By shedding new light on the semiregular polyhedra of space, Alicia Boole Stott's method makes it possible to go further and explore objects in the fourth dimension. In particular, she was able to set out in search of semiregular polytopes.
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Math for everyoneN°84Nov 17, 2022The Malfatti circles
In a triangle, how should three non-overlapping circles be chosen so as to minimize the area of the triangle left over once the three circles are removed? A natural solution, involving tangents within the triangle, is not the best one, but it gives rise to interesting problems.
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History and CultureN°208Oct 21, 2022Harold Scott MacDonald Coxeter: A long life
H.S.M. Coxeter was born on February 9, 1907, in Kensington, Great Britain. Since both his parents were art lovers, music became his first passion.
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Math for everyoneN°205Apr 19, 2022Graphical statics
Have you heard of "graphical statics"? Rooted in mathematics, particularly geometry, it is the art of balancing the forces acting on a body… without any calculations. Surprisingly, the discipline originated long before vectors were introduced!
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