A rigid Boolean algebra that admits the elimination of Q21
Volume 142 / 1993
                    
                    
                        Fundamenta Mathematicae 142 (1993), 1-18                    
                                        
                        DOI: 10.4064/fm-142-1-1-18                    
                                    
                                                Abstract
Using ♢ , we construct a rigid atomless Boolean algebra that has no uncountable antichain and that admits the elimination of the Malitz quantifier $Q_1^2$.