The number of countable isomorphism types of complete extensions of the theory of Boolean algebras
Paul Iverson · Colloquium Mathematicum · 1991
There is a conjecture of Vaught [17] which states: Without The Generalized Continuum Hypothesis one can prove the existence of a complete theory with exactly $ω_1$ nonisomorphic, denumerable models. In this paper we show that there is no such theory in th