Set Theory of the Continuum

Volume 26 of the series Mathematical Sciences Research Institute Publications pp 357-405

Vive la Différence I: Nonisomorphism of Ultrapowers of Countable Models

  • Saharon ShelahAffiliated withDepartment of Mathematics, Hebrew University

* Final gross prices may vary according to local VAT.

Get Access


We show that it is not provable in ZFC that any two countable elementarily equivalent structures have isomorphic ultrapowers relative to some ultrafilter on ω.