In this talk we will don't speak about Joseph-Louis Lagrange (1736-1813) but about Lagrange's reception at the nineteenth Century. "Who read Lagrange at this Times?", "Why and How?", "What does it mean being a mathematician or doing mathematics at this Century" are some of the questions of our conference. We will give some elements of answers and the case Lagrange will be a pretext in order to explain what are doing historians of mathematics: searching archives and – thanks to a methodology – trying to understand, read and write the Past.
Lagrange - mathematical press - complete works - bibliographic index of mathematical sciences (1894-1912) - Liouville - Boussinesq - Terquem[-]

Benoît Mandelbrot and Marcel-Paul Schützenberger first met at the Institut Poincaré in Paris in the 1950s, when both were working on topics in the then novel field of information theory. Their paths crossed again at the other end of the Atlantic on the East Coast where they were drawn into discussions on formal models of language. This was an important topic in the U.S. because these models could be useful for automatic translation, and for automatic coding of information and of programs for digital computers. In the late 1950s, a vivid debate raged whether probabilistic models or rather grammatical or rule-based models were appropriate for describing (natural) language, with notably Noam Chomsky and his students attacking the probabilistic approach. As Mandelbrot arrived in the U.S., the probabilistic model of language he had developed in his PhD became part of the discussion. Also Schützenberger got involved in the debate with his early work on coding theory. Eventually, Chomsky's arguments against probabilistic models would prevail. As a result, Mandelbrot's research went into a slightly different direction that would bring him to fractal geometry, whereas Schützenberger, via his frequent visits to the U.S., became one of the architects of the mathematics behind formal languages and coding theory.[-]

The introduction of wavelets in the mid 80's has significantly reshaped some areas of the scientific landscape by establishing bridges between previously disconnected domains, and eventually leading to a new paradigm. This generally accepted-yet loose-claim can be given a more precise form by exploiting bibliometric databases such as the ISI Web of Science. Preliminary results in this direction will be reported here, based on multiple entries where authors, references, keywords and disciplines are used as nodes of a network in which the links correspond to their co-appearance in the same paper. While the evolution in time of such an « heterogeneous net » gives a quantified perspective on the birth and growth of wavelets as a well-identified scientific field of its own, it also raises many interpretation issues (related, e.g., to automation vs. expertise) whose implications go beyond this peculiar case study.

Keywords : wavelets - history - bibliometry - network, paradigm[-]

La richesse du contenu de l'Encyclopédie nécessite la définition d'un protocole de présentation et d'éclairage critique se déclinant à plusieurs échelles : aux textes de présentations généraux (de tel volume, de tel article ou ensemble d'articles) et notes ponctuelles classiques s'ajouteront à la fois la possibilité de mettre en valeur les nombreux éléments caractéristiques constitutifs du texte encyclopédique (les titres des articles, les désignants, les renvois vers d'autres articles, les signatures des encyclopédistes, les mentions de leurs sources, etc.) et la possibilité d'y articuler finement les annotations permettant d'en éclairer les intérêts et les enjeux. La mise en place d'un tel apparat critique requiert la définition préalable des éléments du texte encyclopédique que nous souhaitons repérer, et des liens qu'ils entretiennent entre eux. Cette politique éditoriale sera ici exposée dans le détail, avec la terminologie qui y est associée.[-]