Mathematical Themes

A comic book introduction to Maryam | Tangente

Iranian mathematician Maryam Mirzakhani (1977–2017) became the first woman to win the Fields Medal in 2014.

A podcast devoted to Ada Lovelace | Tangente

Bababam's "True Story" podcasts tell remarkable true stories that are a pleasure to listen to and share.

Jobs, the economy and why mathematics matters | Tangente

In mid-September, the Institut national des sciences mathématiques et de leurs interactions (INSMI) at the CNRS published a study on the impact of mathematics on the economy and employment.

From coin tossing to stochastic differential equations

Tossing a coin many times naturally leads to an interest in certain types of paths on a line, in a plane, in space… The random nature of these experiments means that their study goes beyond the classical framework of ordinary differential equations.

Hervé Lehning (1948–2022) | Tangente

Tireless in his work, Hervé Lehning devoted his life to sharing the mathematics he loved so deeply and making it accessible without sacrificing quality, driven above all by a desire to pass on his passion. But he was much more besides.

Roger Apéry and the irrationality of zeta(3)

Greek on his father’s side, Roger Apéry (1916–1994) spent his childhood in Lille (Nord) before moving to Paris in 1926. Living conditions there became difficult following the 1929 crisis and his father’s loss of his engineering job. To escape this environment, he placed his faith in France’s state school system and academic success.

H.S.M. Coxeter: A geometer's long life | Tangente

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.

Late arrivals: great minds who came to mathematics late | Tangente

Few mathematicians reach their first fundamental results late in life. Yet examples exist, even among the most celebrated scholars. The reasons behind this turn toward the queen of the sciences at a mature age are varied, as shown by the paths of Cardano, Napier and Weierstrass.

Inverting the power

The notion of power defined with respect to a circle naturally leads to the notions of inversion and polars. These pedagogical tools, which have vanished from school curricula, are central to the birth of the concept of duality and of representations of non-Euclidean geometry.

A concept with a long history

The power of a point with respect to a circle appears implicitly as early as Book III of Euclid's Elements. This notion, elementary as it may be, would be redefined in the 19th century and become the basis for numerous applications in geometry.

In 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.

A useful power

Talking about the "power of a point with respect to a circle" may seem old-fashioned nowadays. Yet this elegant geometric notion had its heyday and its uses. Its applications to various mathematical questions are highly fruitful.

Tangente Day on 4 December at Arts & Métiers

COME CELEBRATE TANGENTE'S 35TH ANNIVERSARY ON 4 DECEMBER! More than 3,000 visitors in a single day! That is the achievement we pulled off with your help during the last two "Tangente Days," held in 2017 and 2018. On those days, the Musée des Arts et Métiers opened its doors to the public free of charge all day, and we were able to offer you numerous exciting activities from 10 a.m. to 6 p.m.

How to help Tangente

IN A DIFFICULT TIME FOR MAGAZINES As you may know, publishers, printers and newsstands are going through a difficult period.

Proof

Blackjack: fluctuating probabilities | Tangente

Mathematicians have been studying blackjack since the postwar years. They discovered ways to improve players’ performance by applying probabilities both statically (basic strategy) and dynamically (card counting). But casinos changed the rules to protect themselves.

Bridge: Suit Combinations and Probability | Tangente

Bridge (and its ancestor, whist) is, along with chess, one of the two most celebrated games in the West, as the quotation below from Edgar Allan Poe attests — no doubt too flattering. Probability is often invoked in deciding which strategy to adopt.

Board games and chance: the maths of dice | Tangente

What role does chance play in a board game? It can vary widely, ranging from total dominance, where players have no say at all, to complete absence. Between the two extremes, the strategies of many games rely on optimizing probabilistic principles.

Nimbers applied to the game of Cram

The game of Cram consists in placing dominoes on a grid. Remarkably, its study can be reduced, via the definition of a category of mathematical objects called "nimbers", to the Marienbad matchstick game.

Half-move advantage in combinatorial games | Tangente

In a board game, it is fairly common, partway through a match, to feel that you are ahead of (or behind) your opponent. Through the example of Domineering, this article invites you to discover how John Conway formalized this notion.