Scientists and students around the world are familiar with concepts that bear his name: the Laplacian, the Laplace–Gauss distribution, the Laplace transform, Laplace matrices, and many others. Yet Pierre-Simon Laplace remains little known. Following Leonhard Euler, Henri Poincaré, Évariste Galois, and Blaise Pascal, Tangente wishes to introduce you to this extraordinary scientist.
An exceptional scientist, certainly, but much more besides ----------------------------------------------------
In this issue, you will discover the many facets of this figure: a towering scientist, of course, sometimes nicknamed "the French Newton". His research spans numerous branches of mathematics and physics. His chief concern was to understand the world and its physical laws. Building on Newton's theory of gravitation, he succeeded in explaining many phenomena that were puzzling at the time, including the relationship between the orbits of Saturn and Jupiter and the motion of the tides; these discoveries appear in his Traité de mécanique céleste.
His innovative approach to probability helped establish the subject as part of pure mathematics, drawing in particular on analysis, as illustrated by his idea of defining generating functions. The philosophical introduction to his Théorie analytique des probabilités reveals his commitment to addressing fundamental questions of social life.
Laplace's genius lay in his ability to develop, for each problem he tackled, a mathematical theory that proved useful beyond its original purpose. His approach to science was founded "on the eternal principles of reason, justice, and humanity"; he replied to Napoleon: "God is a hypothesis I have had no need of. "
His philosophical outlook was both original and judicious; it led him to define determinism, devise a cosmogonic model, and explore the question of the solar system's stability.
Laplace's political career should not be overlooked: he contributed to the development of France's grandes écoles, served as a senator and briefly as Minister of the Interior, became a count of the Empire, and then, following the Restoration, a marquis and peer of France.
An active member of the Académie des sciences and a gifted writer, he was one of the few mathematicians to be elected to the Académie française. He opened up many avenues of scientific inquiry that scholars such as Carl Friedrich Gauss, Adrien-Marie Legendre, and Henri Poincaré would pursue with great success.
Bertrand Hauchecorne,
Issue coordinator