The branch locus for one-dimensional Pisot tiling spaces
Volume 204 / 2009
                    
                    
                        Fundamenta Mathematicae 204 (2009), 215-240                    
                                        
                        MSC: Primary 37B05; Secondary 37A30, 37B50, 54H20.                    
                                        
                        DOI: 10.4064/fm204-3-2                    
                                    
                                                Abstract
If $\varphi$ is a Pisot substitution of degree $d$, then the inflation and substitution homeomorphism $\mit\Phi$ on the tiling space ${\cal T}_{\mit\Phi}$ factors via geometric realization onto a $d$-dimensional solenoid. Under this realization, the collection of $\mit\Phi$-periodic asymptotic tilings corresponds to a finite set that projects onto the branch locus in a $d$-torus. We prove that if two such tiling spaces are homeomorphic, then the resulting branch loci are the same up to the action of certain affine maps on the torus.
 
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            