Jean-Jacques Dupas
107 articles published in Tangente
Math for everyoneN°78May 18, 2021Albrecht Dürer and technical drawing
Albrecht Dürer (1471–1528) devised a fascinating straightedge-and-compass construction of the ellipse. It foreshadowed descriptive geometry, which Gaspard Monge (1746–1818) would formalize almost three centuries later.
Read →
Math for everyoneN°199Apr 13, 2021Teja Krašek in Escher's footsteps
Born in Celje, Slovenia, Matjuska Teja Krašek (pronounced "Teyla Krashek") lives and works in Ljubljana. Her work draws on her fascination with symmetry, fractals and, more broadly, the beauty she sees in mathematics. She agreed to share her passion with us.
Read →
N°77Feb 18, 2021Three-dimensional printing
3D printing has enjoyed a real surge in popularity in recent years. Do you know how it works?
Read →
History and CultureN°197Dec 04, 2020Three unsolved problems in geometry
Geometry abounds in problems that remain unsolved. Some date back to the Renaissance! In tribute to Richard Kenneth Guy (1916–2020), here are three, gleaned from his book Unsolved Problems in Geometry (with Hallard Croft and Kenneth John Falconer, Springer, 1991).
Read →
History and CultureN°197Dec 04, 2020Lean: a new library of Alexandria
Building a digital repository of mathematics—a new "Library of Alexandria for mathematics"—is the wildly ambitious collaborative undertaking on which many mathematicians have embarked.
Read →
Math for everyoneN°76Nov 06, 2020Loops in programming
The various types of loops are fundamental programming constructs. Although using them often comes naturally, they nevertheless raise a number of issues, such as whether the program will ever stop. Recursion offers useful solutions.
Read →
History and CultureN°195Jul 14, 2020The history of the Paris meridian
The best-known story in the history of measurement is surely the determination of our planet's circumference...
Read →
Math for everyoneN°194May 21, 2020A game showcasing the richness of combinatorics
Radical X is a compact game packaged in a rectangular box with edges measuring less than 5 cm.
Read →
Math for everyoneN°74Apr 17, 2020Drawing machines
Viewed as geometric loci, curves have always been drawn on a physical surface using instruments—or even machines. The mechanical linkages devised for this purpose can faithfully reproduce the curve under study.
Read →
Math for everyoneN°193Mar 20, 2020Polynomials that make a difference
A polynomial can be evaluated without any multiplication, using addition alone. Charles Babbage based his famous "Difference Engine" on this remarkable property.
Read →
History and CultureN°193Mar 19, 2020Leonardo da Vinci: nature as a source of inspiration
Everything you need to know about Leonardo da Vinci
Read →
Math for everyoneNov 22, 2019The mathematics of pop-up cards
A sheet of paper offers endless opportunities for mathematical play. Origami and paper folding immediately spring to mind. But allowing yourself to cut the paper produces equally interesting results, as pop-up cards show.
Read →