La naissance des éléments, du Big-Bang à la Terre : un siècle d’avancées scientifiques

Le 3 octobre 2025, Sylvie Vauclair, 10h45 à 12h45, Salle Jules Verne, OMP, site Belin

Summary: Since the beginning of the 20th century, the scientific knowledge on the formation of the chemical elements in the Universe, from Big-Bang to Earth, have evolved in spectacular manner, thanks to close interconnections between atomic physics, « sub-atomic » and then nuclear physics, and astrophysics. The close link between the energy produced in stars and the formation of heavy elements, the computations of the first nuclear reactions rates, the important advances induced by the preparation of the « atomic bomb », and many other steps, including the recent discovery of neutron star collisions, led to a general achievement, giving access to the origin, or rather the origins, of most elements of Mendeleev’s periodic table.

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