Unambiguity in Automata Theory

  • Thomas ColcombetEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9118)


Determinism of devices is a key aspect throughout all of computer science, simply because of considerations of efficiency of the implementation. One possible way (among others) to relax this notion is to consider unambiguous machines: non-deterministic machines that have at most one accepting run on each input.

In this paper, we will investigate the nature of unambiguity in automata theory, presenting the cases of standard finite words up to infinite trees, as well as data-words and tropical automata. Our goal is to show how this notion of unambiguity is so far not well understood, and how embarrassing open questions remain open.


Choice Function Regular Language Input Word Finite Tree Deterministic Automaton 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



I am really grateful to Jean-Éric Pin, Gabriele Puppis and Michał Skrypczak for their precious help and their discussions on the topic.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.CNRSUniversité Paris 7 – Paris DiderotParisFrance

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