The question is “quite simple”: how quantum physics will complicate the approach to the atom and particularly its relation to the understanding of the electron? To answer this question and many others of Antoine Beauchamp, Marlène Assié from IJCLab has joined Charlotte Bigg from Centre Alexandre-Koyré as guests on the radio program “Eurêka” of France Culture. The discussion has given a historical overview of the atom concept, from its birth as a philosophical idea in Antiquity, until very recent experiments in which a single strontium atom at rest was photographed. In the process, a few key moments in the evolution of our understanding of the atom were emphasized, such as its redefinition on empirical grounds in the early nineteenth century by Dalton, the fierce debates which followed and the great breakthroughs of the early twentieth century, including the discovery of the atomic nucleus and of its elusive constituent, the neutron. The interview can be followed here.