Stefano Crespi Reghizzi

After graduating in electronic engineering from Politecnico di Milano with computer science pioneer Antonio Grasselli, he met several famous cybernetic scientists at the NATO School on Neural Networksin 1967 who steered him towards a PhD in computer science. During his intense three years at UCLA, he familiarised himself with the emerging theories of the discipline now known as 'computer science' and participated, under the guidance of Leonard Kleinrock, in the development of the ARPA network, from which the Internet would later come. His thesis on learning algorithms in Chomsky’s formal grammars was the first step on the scientific path that he was to follow.

Back at Politecnico, he promoted the new structured programming techniques with their programming languages and started the first courses in Italy on compilers and operating systems. He was invited to become Full Professor in Pisa in 1976 in the Faculty of Information Sciences. Back at Politecnico, he carried out intensive teaching, research, international industrial and academic relations and participated in the management of the institution until his retirement. He had exchanges with several universities including Stanford, UCB, Harvard, Paris-7, Paris-Est, and Max-Plack Inst. Biologische Kybernetik.

The experience he gained in his PhD at UCLA contributed, in the 1980s, to the establishment of the doctoral programme in the field of electronics, computer science, automation and telecommunications, later renamed information engineering, of which he was co-ordinator for three three-year terms. The university reform of 1999 provided an opportunity to rethink the syllabus of specialised courses on the theory of formal languages and compilation techniques of programming languages. The reorganisation into two levels proposed at that time still continues in university teaching todayand is documented in the textbook Formal languages and compilation, now in its third edition with contributions from collaborators.

At the same time, he directed the CNR Study Centre - Information and Automation Technology. With the CNR and the European Science Foundation, he initiated the five-year network project Automata from Mathematics to Applications with the participation of eleven other European countries and Israel, concluded with the publication of the extensive collective work Handbook of automata theory. He collaborates as a research associate with the IEIIT Institute of the CNR.     

Although an individual's research is necessarily focused on a few specialised areas, his interest in both theory and practice led him to find a balance between mathematical-formal study and the design of innovative and complex software systems.  In the theoretical field, his main contributions concern: grammar learning and inference, the study of context-free languages, models of concurrent and parallel systems, relational algebra, automata with different types of memories, syntactic analysis algorithms, associative grammars, grammars for describing 2D pictures. During the years when programming was a new discipline, he contributed to the conceptual development and testing of new languages. In 1968-70, his language for treating graphs was hailed as a pioneer of new methods of structured programming; in 1986, Multi-Micro-Language MML was one of the contenders for the development of codes for interconnected micro-computers and was adopted by ENEL for the real-time control of network devices. Applications were derived from it for the Pentagon's new ADA language, described in the book ADA for multi-processors and realised in industrial prototypes. Algres (1990), a language for databases, and its successor Logres, based on logic instead of relational algebra, then resonated in the international community. These projects required extensive and prolonged group work, with academic and industrial participation and substantial funding. The 1999-2001 European project GEDISAC successfully applied formal language techniques to the design of interactive human-machine interfaces. Research then shifted to complex systems, called compilers, that translate languages into efficiently executable codes on processors and machines with ever-increasing processing capabilities. Through a long and fruitful collaboration with the research division of the company STMicroelectronics, the compiler group which he co-ordinated developed innovative technical solutions to bridge the gap between the sequential nature of traditional algorithms and the increasingly parallel structure of modern processors. In 2010, the PAPAGENO project, a software tool capable of automatically generating syntactic analysis algorithms using parallel computing, became the first Italian project to win the Googleacademic research award. The results of his research are documented in over a hundred scientific articles in international journals and conferences, several of which are still relevant after decades.

In the course of the lively debate on the adoption of English in the teaching of master's degree courses, he held a critical stance focused on preserving the Italian language, aligning himself with the Constitutional Court's ruling on the primacy of the Italian language and with those who fear a rapid future degradation of terminological richness caused by the ousting of Italian from academic use. Broadening his strictly scientific perspective, he has addressed philosophical and theological viewpoints, participating in reflections within the SEFIR (science and faith on the interpretation of reality) research area at the Pontifical Lateran University, and founding the homonymous cultural association in 2021.

He had significant responsibilities in the management of Politecnico di Milano, as a member of the Board of Governors (1994-97) and then as superintendent, delegated by the rector, for telematics and computing systems.

Career highlights kindly provided by professor Crespi Reghizzi in 2023