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UID:www.tcs.tifr.res.in/event/606
DTSTAMP:20230914T125931Z
SUMMARY:Axiomatizing Equality of Expressions
DESCRIPTION:Speaker: Kamal Lodaya (The Institute of Mathematical Sciences\n
 IV Cross Road\nCIT Campus\nTharamani\nChennai 600113)\n\nAbstract: \nAbstr
 act:An axiomatization of equality of regular expressions was given by Arto
  Salomaa in 1966\, using Janusz Brzozowski's "derivatives" in 1964. Volodi
 mir Redko also showed in 1964 that a finite set of axioms is insufficient\
 , so Salomaa used an algorithmic side condition in his system. John Horton
  Conway formulated an algebraic approach in 1971. Albert Meyer and Larry S
 tockmeyer showed in 1972 that the problem requires polynomial space. Dexte
 r Kozen developed a new "inequational" axiomatization using Conway's algeb
 raic ideas in 1994 (requiring no algorithmic side conditions). Jan Rutten 
 suggested using "coalgebraic" ideas in 1999 and Clemens Grabmayer came up 
 with an axiomatization in 2005. This talk surveys these ideas and points o
 ut challenges remaining after 50 years of work in this area.\n
URL:https://www.tcs.tifr.res.in/web/events/606
DTSTART;TZID=Asia/Kolkata:20150618T160000
DTEND;TZID=Asia/Kolkata:20150618T170000
LOCATION:A-212 (STCS Seminar Room)
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