The department mourns the death of Prof. Thomas Streicher
Professor Dr. Thomas Streicher (11.02.1958 – 02.01.2025)
2025/01/15
On January 2, 2025, our recently retired colleague Professor Dr. Thomas Streicher died after suffering a serious illness.
Professor Dr. Thomas Streicher served as professor of the TU Darmstadt starting in 1995 up to his retirement on 1st of April 2024, initially in the research group ,,Logic and the Mathematical Foundations of Computer Science” and then from 2004 on in the then newly founded research group ,,Logic’’ at the Department of Mathematics.
Professor Streicher received his PhD degree in 1988 from the University of Passau under the supervision of Professors Manfred Broy and Martin Wirsing (,,Correctness and Completeness of a Categorical Semantics of the Calculus of Constructions’’) and did his Habilitation in 1994 at LMU Munich (,,Investigations into Intensional Type Theory’’).
Besides numerous journal and proceedings publications, Professor Streicher authored two monographs ,,Semantics of Type Theory’’ (Birkäuser 1991) and ,,Domain-theoretic foundations of functional programming’’ (World Scientific Publishing 2006).
Professor Streicher had far reaching mathematical interests and was internationally highly acknowledged for this seminal contributions to categorical logic, the logical foundations of functional programming, models for constructive type theories and as one of the founders of homotopy type theory (HoTT) which has received – starting in the 2000’s – enormous worldwide attention in connection with Vladimir Voevodsky’s program of ,,Univalent Foundation of Mathematics’’. The theoretical foundation of HoTT largely rests on an article of Thomas Streicher with Martin Hofmann (1965-2018) from 1994, which in 2014 – 20 years after its publication – was awarded in Vienna with the ,,LICS Test-of-Time Award’’. In fact, this paper contains the first formulation of a version of the ,,univalent axiom’’ (under the name “universe extensionality”) made subsequently famous in its full generality by Voevodsky. In the statement of the LICS Test-of-Time Award it says ,,This paper opened a series of investigations leading to the development of homotopy type theory, an area of intense current research that touches on the very foundations of the field. … The results were quite surprizing at the time” and that the paper constitutes ,,an essential forerunner of more recent developments on univalent foundations’’.
Professor Thomas Streicher was a dedicated academic teacher who supervised and mentored many diploma and master students, PhD students and postdoctoral researchers some of which are now university professors themselves in e.g. France, Netherlands, UK and the USA.
The Department of Mathematics of Technical University of Darmstadt mourns the death of an internationally highly recognized and kind colleague and will keep him in lasting memory.