Menas Theorem and Strong Compactness on \(P_\kappa(\lambda)\)

Catalina Torres (U of Barcelona)

Sep 09. 2026, 14:00 — 14:30

Higher forms of stationarity and reflection on \(P_\kappa(\lambda)\) provide natural two-cardinal analogues of classical reflection principles. This talk focuses on their interaction with strong compactness and projection/lifting phenomena in the spirit of Menas' theorem. After briefly recalling the motivation for extending stationary reflection to the two-cardinal setting, recent joint work with Hiroshi Sakai will be discussed showing that strong compactness does not suffice for \(2\)-stationarity on \(P_\kappa(\kappa^+)\). It will also be shown that Menas-type arguments behave differently for higher stationarity: while an analogue of Menas' theorem holds for \(1\)-stationarity under suitable assumptions, the corresponding lifting phenomenon for \(2\)-stationarity can consistently fail. These results provide further evidence that higher stationarity on \(P_\kappa(\lambda)\) exhibits genuinely new behavior beyond ordinary stationarity.
 

 

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\bibitem{Schanker}
{Jason A. Schanker}.
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\bibitem{Torres}
{M. Catalina Torres}.
\emph{Higher Stationarity and Derived Topologies on \(P_\kappa(A)\)}.
arXiv:2402.00805, to appear in the Israel Journal of Mathematics.

\bibitem{TorresSakai}
{M. Catalina Torres and Hiroshi Sakai}.
\emph{Strong Compactness and Two-Stationarity on \(P_\kappa(\kappa^+)\)}.
Manuscript in preparation.

\end{thebibliography}

Further Information
Venue:
ESI Boltzmann Lecture Hall
Associated Event:
FLINTA* in Set Theory (Workshop)
Organizer(s):
Hope Duncan (U Leeds)
Azul Fatalini (U Leeds)
Martina Iannella (TU Wien)
Siiri Kivimäki (U Helsinki)
Sandra Müller (TU Wien)
Lena Wallner (TU Wien)