Hilbert's tenth problem
Multiplicative equations over commuting matrices
Proceedings of the seventh annual ACM-SIAM symposium on Discrete algorithms
Hilbert's tenth problem and paradigms of computation
CiE'05 Proceedings of the First international conference on Computability in Europe: new Computational Paradigms
Decision Problems for Probabilistic Finite Automata on Bounded Languages
Fundamenta Informaticae - MFCS & CSL 2010 Satellite Workshops: Selected Papers
| Hi-index | 5.25 |
We prove that for given morphisms g,h:{a"1,a"2,...,a"n}-B^*, it is decidable whether or not there exists a word w in the regular language a"1^*a"2^*...a"n^* such that g(w)=h(w). In other words, we prove that the Post Correspondence Problem is decidable if the solutions are restricted to be from this special language. This yields a nice example of an undecidable problem in integral matrices which cannot be directly proved undecidable using the traditional reduction from the Post Correspondence Problem.