Series: Penn State Logic Seminar

Date: Monday, October 29, 2001

Time: 10:10 - 11:00 AM

Place: 320 Willard Building

Speaker: Mirna Dzamonja, Mathematics, University of East Anglia

Title: Some Usual and Some Unusual Combinatorial Principles


We discuss two recent papers.  The first is joint with Michael Hrusak
and Justin Moore and concerns various generalisations of the weak
diamond which allow us to calibrate exactly how much of diamond is
necessary for certain well-known constructions classicaly derived from
diamond, such as that of a Suslin tree.  These constructions are
mostly limited to omega_1.  The other paper by the speaker considers
some classical diamond-like principles, such as club, but in the
context of cardinals above beth_omega.  Using pcf theory it is proved
that certain versions of this principle at such cardinals follow
simply from the relevant instances of GCH.