Physics and Art: introducing light-matter interaction by looking at famous paintings

The colour of an object is a subjective sensation produced by a series of phenomena connected to the interaction between matter and electromagnetic waves. Our eyes incessantly convey images and information to us, but hardly ever do we stop to consider their physical origin. We are enchanted by the colours of spring, we marvel at the beauty of a butterfly’s wings, we are carried away by the sight of a picture and yet we ignore that these sights are the result of the interaction between light in the environment and the material of the bodies’ surface. Such an attitude originates spontaneous explanatory hypotheses which tend to take root, such as those of colour being one of the properties of an object and light being a neutral entity which gives luminosity to objects. This position does not allow a scientific approach to reality and therefore it does not allow quantification of the phenomena. Unfortunately scientific models of phenomena often require mathematical or geometrical formalism, and therefore they are often seen by the students as being an end in themselves, having no evidence in reality and no practical use; for this reason, they may not be considered to represent an actual advance in learning.Art is probably the most suitable context to introduce the phenomena connected to light-matter interaction, since painters know well - at least from a practical point of view - that the final result of their work is given by their capability to control these phenomena.