L Systems

  • Lila Kari
  • Grzegorz Rozenberg
  • Arto Salomaa


L systems are parallel rewriting systems which were originally introduced in 1968 to model the development of multicellular organisms [L1]. The basic ideas gave rise to an abundance of language-theoretic problems, both mathematically challenging and interesting from the point of view of diverse applications. After an exceptionally vigorous initial research period (roughly up to 1975; in the book [RSed2], published in 1985, the period up to 1975 is referred to as “when L was young” [RS2]), some of the resulting language families, notably the families of D0L, 0L, DT0L, E0L and ET0L languages, had emerged as fundamental ones in the parallel or L hierarchy. Indeed, nowadays the fundamental L families constitute a similar testing ground as the Chomsky hierarchy when new devices (grammars, automata, etc.) and new phenomena are investigated in language theory.


Number System Growth Function Regular Language Artificial Life Bounded Delay 
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© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Lila Kari
  • Grzegorz Rozenberg
  • Arto Salomaa

There are no affiliations available

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