Ernst-Rüdiger Olderog: A Life for Meaning

While it is indubitably impossible to summarize all the many important aspects of Ernst-Rüdiger Olderog’s scientific contributions and to do justice to each and every one of the areas that he contributed to, it is remarkably easy to identify and characterize the common core behind his investigations. An important leitmotif in his research agenda is semantics, the study of meaning. Even if a significant share of his research does not study semantics in and of itself, but rather as a means to an end, Ernst-Rüdiger Olderog stands out as having recognized the significance of semantics as an important foundation in the first place. He accurately observes how crucial the study of the meaning of a mathematical object of study is for the progress of a research area as a whole, as well as for achieving the individual results he is looking for. The most prominent results that Ernst-Rüdiger Olderog’s research enables are various forms of correctness results, as are engraved in the name of his research group: “Correct System Design”. The main analytic tool to obtain them, though, is ErnstRüdiger Olderog’s dedication to semantics. Be it to develop an understanding of concurrency by logical communication formulas to algebraic process terms and further to Petri nets [21], to understand sequential and concurrent programs for the purpose of verification [3,2], or specification and verification techniques for real-time systems [26]. A strong devotion to semantics is a pervasive aspect of his research throughout his career [27,4,28,5,21,3,22,12,26,11], whether on communicating processes [28,27], concurrency at large [5,4,21], real-time systems [26,22] and specification languages for richer realtime systems [15,12], traffic agents [9,8], or games for distributes systems synthesis [11]. Ernst-Rüdiger Olderog’s attention to semantics is quite prominently featured already in the first column of a paper on his first research results [20]: