On the Undecidability of Universality for Timed Automata with Minimal Resources
نویسندگان
چکیده
In 1994 Alur and Dill introduced timed automata and showed that universality was undecidable there. Since then it has been shown that under certain restrictions the problem becomes decidable. But the frontier between decidability and undecidability is still vast. We aim at narrowing this gap considerably. Our main accomplishment is to prove that universality stays undecidable over weakly monotonic time when restricting to a single state, a single symbol and clock comparisons to 0 and 1 only. We further propose that over strongly monotonic time the problem stays undecidable for timed automata with one state and one symbol only.
منابع مشابه
Undecidability of Universality for Timed Automata with Minimal Resources
Timed automata were introduced by Alur and Dill in the early 1990s and have since become the most prominent modelling formalism for real-time systems. A fundamental limit to the algorithmic analysis of timed automata, however, results from the undecidability of the universality problem: does a given timed automaton accept every timed word? As a result, much research has focussed on attempting t...
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