Games for graded modal substitution calculus

Graded modal substitution calculus (GMSC) and its variants has been used for logical characterizations of various computing frameworks such as graph neural networks, ordinary neural networks and distributed computing. In this paper we introduce two different semantic games and formula size game for graded modal substitution calculus and its variants. Ultimately, we show that the formula size game characterizes the equivalence of classes of pointed Kripke models up to programs of GMSC of given size. Thus, the formula size game can be used to study the expressive power mentioned characterized classes of computing models. Moreover, we show that over words GMSC has the same expressive power as deterministic linearly tape-bounded Turing machines also known as deterministic linear bounded automata.