Fontana cowrote the White Manifesto, the first declaration of Spatialism, in Buenos Aires in 1946. Following the new discoveries in physics—from relativity to quantum mechanics—this manifesto promoted the use of new technology and the expansion of the artwork into the fourth dimension. Three years later, in Milan, Fontana started his Spatial Environments, experiments with light and space. They included the use of neon tubes that would set the course for future developments in installation art. Fontana’s multidisciplinary approach broadened the notion of the art experience to embrace the space surrounding the viewer.