A cofinality-preserving small forcing may introduce a special Aronszajn tree



It is relatively consistent with the existence of two supercompact cardinals that a special Aronszajn tree of height \({\aleph_{\omega_1+1}}\) is introduced by a cofinality-preserving forcing of size \({\aleph_3}\).


Weak square Aronszajn tree Small forcing 

Mathematics Subject Classification (2000)

Primary 03E35 Secondary 03E05 03E04 


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.School of Mathematical SciencesTel Aviv UniversityTel AvivIsrael

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