Pro c. 16th Eur. Meeting on Cyb ernetics and Systems Research EMCSR, Vienna, April 2 { 5, 2002, vol. 2, pp. 934-939 = Cyb ernetics and Systems, R. Trappl, ed., Austrian So c. for Cyb ernetics Studies. The Scienti c Work of Wilhelm Cauer and its Key Position at the Transition from Electrical Telegraph Techniques to Linear Systems Theory Rainer Pauli Munich UniversityofTechnology D { 80290 Munich Germany email:
[email protected] Abstract together with their mutual relations which are de ned by the frequency-indep endent holonomic constraints The pap er sketches a line of historical con- imp osed byinterconnection rules. Therefore, network tinuity ranging from telegraph pioneers and theory ab initio was set up as a purely mathemati- early submarine cable technology of the 19th cal discipline. Most notably, under the standard as- century to some asp ects of mo dern systems sumptions of linearity and time-invariance, the the- and control theory. Sp ecial emphasis is laid ory of passive networks is equivalent to the theory of on the intermediary role of the scienti c work dissipative mechanical systems that p erform small os- of Wilhelm Cauer 1900-1945 on the synthe- cillations around a stable equilibrium. Esp ecially in sis of linear networks. [ ] his early pap ers on network synthesis Cauer, 1926 , [ ] Cauer, 1931b Cauer's mathematical starting p ointis this relation to classical analytical mechanics. Nev- 1 Intro duction ertheless, it is fair to recall that the motivation and While it is almost commonplace that mo dern metho ds detailed structure of the problem was rmly ro oted of data compaction, co ding and encryption in to day's in electrical telegraph techniques of the 19th century, communications all have their ro ots in the techniques esp ecially in submarine cable transmission problems; [ ] of the telegraph pioneers Beauchamp, 2001 , analo- [ ] [ ] [ see Belevitch, 1962 , Darlington, 1984 and Wunsch, gous facts concerning the evolution of classical net- ] 1985 .