The forms of symmetry – Four stories of science, from chirality to spin

Is it possible to popularize science as historians do? To talk about science without becoming too difficult or, on the contrary, trivial?

This essay answers these questions through the telling of four “scientific stories” united by the theme of symmetry. The first story deals with the discovery of chirality and examines its consequences in chemistry and biochemistry.

The second concerns thermodynamics, for which the time asymmetry of macroscopic transformations (irreversibility) and the “arrow of time” as a consequence play a central role.

The third story is devoted to phase transitions, seen as examples of symmetry breaks.

Finally, the last one focuses on a fundamental symmetry of elementary particles, spin.

The short biographies of the scientists in the appendix underscore the book’s epistemological approach, which aims to tell the story of science “in the manner of historians” and has as goal the most open and multidisciplinary popularization of science possible.

Paolo Ghigna is a full professor in Physical Chemistry at the University of Pavia. He participates in several national and international research projects and has numerous publications to his credit. He is author of a chapter for the series “Electroanalytical Chemistry: A Series of Advances” and editor of the “Complex Oxides” section of the Encyclopedia of Materials: Electronics. He is also co-author of the textbook Foundations of Physical Chemistry (with G. Spinolo, 2026).