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Dive into the fascinating world of mathematics with our captivating articles, written by passionate experts. Whether you are a curious amateur or a seasoned mathematician, our articles cover a wide range of topics, from fundamental concepts to the latest discoveries, including practical applications and philosophical reflections.
Essential tools of analysis
Given a somewhat complicated function, who has not wished they could replace it with a much simpler one that "behaves in the same way," such as a polynomial? Taylor expansions make this possible in almost every case—at least locally!
The centenary of Gustave Eiffel's death
Editorial
How long is a fraction of a second? In everyday life, we would simply say that it is a very short time; in mathematics, however, we would be led to look for two integers—a numerator and a larger denominator—with which to quantify it.
Gilles and the mathematics culture and games fair | Tangente
Two passions guided Gilles throughout his life: puzzles and popularizing mathematics.
The culture of Tangente | Tangente
From the outset, Tangente envisioned a whole world of worlds: mathematics linked to literature and poetry, to music; a publication opening the door to the wonderful world of logical puzzles; mathematics as a whole world in itself, extraordinarily vibrant and fully in tune with the latest technological advances. Above all, it stood for openness to the world, through writing that aimed to be accessible to everyone.
Bridge: a bridge between games and statistics | Tangente
Bridge begins with an auction, in which players commit to taking a minimum number of tricks during play. Statistical methods make it possible to rationalize this decision-making process.
A brand-new game | Tangente
"What's New?... in the Henhouse!" is the latest game from Julien le Magicien. The aim is to make 9 by combining several cards.
Maths through song | Tangente
"Today, we're doing maths!" That is the message Adrien Deslypper and Stéphane Delobel (along with a few accomplices), two high school teachers from Hauts-de-France, bring to their students every day.
2024: a new year with many properties
What spectacular mathematical advances, major scientific discoveries and gains in knowledge does the new year have in store for us? It is hard to say! What is certain is that the natural number 2024 abounds in wonderful arithmetic and combinatorial properties…
Tributes to a puzzle maker
This article brings together several puzzles, some created especially as a tribute to Gilles Cohen and his tireless work creating puzzles.
Mathematicians make progress on coloring
Coloring problems are often very simple to state and may appeal to many amateur mathematicians. Unfortunately—or perhaps fortunately?—they conceal deep difficulties that continue to tax the mathematical community. A new breakthrough was made recently.
PISA: the plunge | Tangente
Released in December, the results of the 2022 PISA survey (the Programme for International Student Assessment, which assesses 15-year-olds) show a sharp decline in French students’ mathematics performance.
Mathematics, the key to the future | Tangente
More than 180 leading figures from the worlds of science, business and industry warned in the December 5 issue of Le Monde that France is losing ground as a scientific and mathematical power.
Inflation: a scam? | Tangente
Inflation is falling, but prices are rising: are we being lied to? No—sadly, this is normal! Saying that the price index is rising means that "the" function representing prices is increasing.
The "A Matter of Logic" column | Tangente
"A Matter of Logic" is a weekly column in the newspaper Le Monde, written since 1997 by Gilles Cohen and Élisabeth Busser. In 2000, it earned them the D’Alembert Prize for popularizing mathematics, awarded by the Société mathématique de France.
A form of harmony between geometry and arithmetic
Many mathematicians have taken an interest in figurate numbers. But their concerns have not always been the same! In ancient times, people sought to construct and represent numbers using counters. The resulting shapes illustrate a host of arithmetic relationships.
Mathematics and literature | Tangente
Gilles Cohen has always championed breaking down the divide between literary and scientific backgrounds. To him, the two are not only perfectly compatible but also mutually enriching.
Francesco Maurolico's extensions
A member of a Greek family that emigrated to Sicily after the fall of Constantinople, Francesco Maurolico was born in Messina in 1494 and died there in 1575. He entered the Church at the age of 27, proposed an extension of figurate numbers, and established many of their arithmetic properties.
An inventory of arithmetic puzzles | Tangente
Figurate numbers, which provide a visual representation of integers, form a wonderful bridge between geometry and arithmetic. Some properties in either field can be reformulated in the other, and vice versa! New questions naturally arise…
A new life for figurate numbers
Figurate numbers entered Arabic mathematics through Thabit ibn Qurra’s translation of the work of the mathematician and philosopher Nicomachus of Gerasa. Thabit’s name is associated with Thebit numbers (the "e" replacing the "a" in medieval Latin transcription).