%0 Conference Paper %B IFIP International Conference on Theoretical Computer Science (IFIP TCS) %D 2014 %T Towards a Coalgebraic Chomsky Hierarchy %A Alexandra Silva %A SergeyGoncharov %A Stefan Milius %C Rome, Italy %I Springer %V 8705 %X

The Chomsky hierarchy plays a prominent role in the foundations of the theoretical computer science relating classes of formal languages of primary importance. In this paper we use recent developments on coalgebraic and monad-based semantics to obtain a generic notion of a T-automaton, where T is a monad, which allows the uniform study of various notions of machines (e.g. finite state machines, multi-stack machines, Turing machines, valence automata, weighted automata). We use the generalized powerset construction to define a generic (trace) semantics for T-automata, and we show by numerous examples that it correctly instantiates for the known classes of machines/languages captured by the Chomsky hierarchy. Moreover, our approach provides new generic techniques for proving expressivity bounds of various machine-based models.

%8 September %> https://haslab.uminho.pt/sites/default/files/xana/files/1401.5277v3.pdf