Artists and Gamblers on the Way to Quantum Physics

The representation space of Renaissance painting is compared to the representation space of quantum physics in [this chapter]. The action of a “semi-transparent” mirror splitting the trajectory of a photon, or any quantum particle, resembles the action of “Alberti’s window” in painting. According to Alberti, painting must recreate a view through a window. To accomplish this task, the light coming from the scene (to be painted) must be caught by the painter’s eye and projected on the plane surface of an ideal veil. The pictorial image results from a “double projection,” for that window acts both as a glass intersecting the visual pyramid and as a mirror reflecting the painter’s eye. When Narcissus realizes how a mirror acts, the shadow which he observes allows him to see another side of himself. When physicists realize how quantum interference acts, “photon-shadows” become “observables.” The awareness shared by Narcissus, Renaissance perspectivists, and quantum observers involves a revision of the function of shadow with respect to the Platonic condemnation and to the “fantastic” conception of the classic world. In the girl’s attempt to fix her lover’s image (told by Pliny), one can already see a “measuring her self against the other” that Plato’s myth had not envisaged. Despite the separation from the young man, the image she drew, the “artificial” representation, would maintain the link (of her self) with the “other.” This view of painting giving shape to “relational” forms marks itself off from a view of science describing “objective” properties of physical reality, hence losing or denying any link between the scientist-observer and the observed object.