Pioneer of string theory in the early 1970s, later on he became better known for his work with Giuliano Preparata at the Italian Institute for Nuclear Physics (INFN); During the 1970s, along with Sergio Fubini, Paolo Di Vecchia and Gabriele Veneziano, Del Giudice was at the centre of an active school of theoretical physicists with close connections to Italy (with one of the Italian INFN and MIT financed "Bruno Rossi" exchange programs).
[1] For many years he was involved in quantum field theory and its relations with the physics of collective, coherent processes.
He pioneered the quantum field theory of soft matter, focusing mainly on the structure of liquid water; in the latter part of his life, he also investigated, together with Luc Montagnier, the relation between water and living matter.
Professor Del Giudice was awarded the Prigogine Medal in 2009.
On that occasion, he delivered a plenary lecture entitled "The interplay of Quantum Field Theory and Thermodynamics of Irreversible Processes as a conceptual basis for Biology and Ecosystem Dynamics".