Uniform Decision Problems for Certain Restricted Classes of Nite Monoid-presentations { a Survey on Recent Undecidability Results
نویسنده
چکیده
It is well-known that many decision problems are undecidable in general for the class of all nite monoid-presentations. Here we consider the question of which of these problems remain undecidable even for very restricted classes of nite monoid-presentations. The restrictions we are interested in concern the number of generators admitted and the condition that each nite monoid-presentation considered has a decidable word problem. As we will see many of these problems remain undecidable even for these restricted classes of nite monoid-presentations. This follows from recent results on the behavior of the Knuth-Bendix completion procedure (Sattler-Klein 1996) and a reened version of Markov's embedding lemma (Madlener and Otto 1997).
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