State Space Reduction For Parity Automata

Authors Christof Löding, Andreas Tollkötter

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Christof Löding
  • RWTH Aachen University, Germany
Andreas Tollkötter
  • RWTH Aachen University, Germany

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Christof Löding and Andreas Tollkötter. State Space Reduction For Parity Automata. In 28th EACSL Annual Conference on Computer Science Logic (CSL 2020). Leibniz International Proceedings in Informatics (LIPIcs), Volume 152, pp. 27:1-27:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)


Exact minimization of ω-automata is a difficult problem and heuristic algorithms are a subject of current research. We propose several new approaches to reduce the state space of deterministic parity automata. These are based on extracting information from structures within the automaton, such as strongly connected components, coloring of the states, and equivalence classes of given relations, to determine states that can safely be merged. We also establish a framework to generalize the notion of quotient automata and uniformly describe such algorithms. The description of these procedures consists of a theoretical analysis as well as data collected from experiments.

Subject Classification

ACM Subject Classification
  • Theory of computation → Formal languages and automata theory
  • Theory of computation → Automata over infinite objects
  • Theory of computation → Regular languages
  • automata
  • ω-automata
  • parity
  • minimization
  • state space reduction
  • deterministic
  • simulation relations


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