Complexity of E0L Structural Equivalence

@article{Salomaa1995ComplexityOE,
  title={Complexity of E0L Structural Equivalence},
  author={Kai Salomaa and Derick Wood and Sheng Yu},
  journal={RAIRO Theor. Informatics Appl.},
  year={1995},
  volume={29},
  pages={471-485}
}
We show that the EOL structural equivalence problem is logspace hard for deterministic exponential time. Also, we show that this question can be solved in linear space by a synchronized alternating Turing machine, and thus establish an exponential space upper bound for its complexity. The equivalence of finite tree automata is shown to be logspace reducible to context-free structural equivalence. The converse reduction is well known and thus context-free structural equivalence is complete for… 
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Background Citations
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4 Citations

On Computational Complexity of Basic Decision Problems of Finite Tree Automata
This report focuses on the following basic decision problems of nite tree automata: nonemptiness and intersection nonemptiness. There is a comprehensive proof of EXPTIME-completeness of the…
Structural Equivalence and Et0l Grammars X Structural Equivalence and Et0l Grammars 1
For a given context-sensitive grammar G we construct ET0L grammars G 1 and G 2 that are structurally equivalent if and only if the language generated by G is empty, which implies that structural…
On Simultaneous Rigid E-Unification
Automated theorem proving methods in classical logic with equality that are based on the Herbrand theorem, reduce to a problem called Simultaneous Rigid E-Unification, or SREU for short. Recent dev…
L Systems
TLDR
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.

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