It’s so tiny that even a million of them placed in line would be no thicker than a sheet of paper. It can destroy or heal and be used in medical diagnoses or as an access key to the realm of the infinitely small. Humanity’s curse or salvation? The atom is the basic building block of matter, its nucleus fuels the Sun and could be an eternal source of safe, clean energy. This text is targeted at non-specialists and addresses prejudices that have always plagued the atom; it provides a comprehensive account of our understanding of atoms, ranging from the dawn of nuclear physics to modern atomic models, up to recent energy studies, and touches upon fields such as nanomaterials, medicine, and communication.

Piero Martin teaches Physics at the University of Padova, heads a European task force involving over 300 researchers, and is a fellow of the American Physical Society.

Alessandra Viola is a freelance science journalist; in 2013 she won the first Popular Science Award of the Italian Book Association.