Sh:326

• Shelah, S. (1992). Vive la différence. I. Nonisomorphism of ultrapowers of countable models. In Set theory of the continuum (Berkeley, CA, 1989), Vol. 26, Springer, New York, pp. 357–405. arXiv: math/9201245 DOI: 10.1007/978-1-4613-9754-0_20 MR: 1233826
  See [Sh:326a]
• Abstract:
  We show that it is not provable in ZFC that any two countable elementarily equivalent structures have isomorphic ultrapowers relative to some ultrafilter on \omega.
• Version 1995-09-04_10 (55p) published version (49p)

@incollection{Sh:326,
 author = {Shelah, Saharon},
 title = {{Vive la diff\'erence. I. Nonisomorphism of ultrapowers of countable models}},
 booktitle = {{Set theory of the continuum (Berkeley, CA, 1989)}},
 series = {Math. Sci. Res. Inst. Publ.},
 volume = {26},
 year = {1992},
 pages = {357--405},
 publisher = {Springer, New York},
 mrnumber = {1233826},
 mrclass = {03C20 (03C15 03E35)},
 doi = {10.1007/978-1-4613-9754-0_20},
 note = {\href{https://arxiv.org/abs/math/9201245}{arXiv: math/9201245}},
 arxiv_number = {math/9201245},
 referred_from_entry = {See [Sh:326a]}
}