Isomorphisms of quotients of FDD-algebras
arXiv:1310.1353
Abstract
We consider isomorphisms between quotient algebras of associated with Borel ideals on and prove that it is relatively consistent with \textbf{ZFC} that all of these isomorphisms are trivial, in the sense that they lift to a *-homomorphism from into itself. This generalizes a result of Farah-Shelah who proved this result for centers of these algebras (in its dual form). We also use a simpler forcing notion and completely remove the large cardinal assumption used by Farah-Shelah.