Transitive arrangements of algebraic systems (Q1595482)

The author introduces the notion of a transitive arrangement \(T^{\ast}\) of a countable family of complete predicative theories \(T_{i}\), \(i\in\omega\), which are Morley expanded, in an exact pseudoplane. The theory \(T^{\ast}\) is transitive. Moreover, \(T^{\ast}\) is stable (superstable, \(\omega\)-stable, small, an \(n\)-theory) if and only if so are all of \(T_{i}\), \(i\in\omega\). The spectrum function of \(T^{\ast}\) is calculated.