%0 Journal Article
%T Shifts with Decidable Language and Non-Computable Entropy
%A Peter Hertling
%A Christoph Spandl
%J Discrete Mathematics & Theoretical Computer Science
%D 2008
%I Discrete Mathematics & Theoretical Computer Science
%X We consider subshifts of the full shift of all binary bi-infinite sequences. On the one hand, the topological entropy of any subshift with computably co-enumerable language is a right-computable real number between 0 and 1. We show that, on the other hand, any right-computable real number between 0 and 1, whether computable or not, is the entropy of some subshift with even polynomial time decidable language. In addition, we show that computability of the entropy of a subshift does not imply any kind of computability of the language of the subshift.
%U http://www.dmtcs.org/dmtcs-ojs/index.php/dmtcs/article/view/640