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Mar 19, 2019 at 16:44 answer added Noah Schweber timeline score: 7
Oct 15, 2012 at 1:19 history edited Noah Schweber CC BY-SA 3.0
added 90 characters in body
Oct 15, 2012 at 1:18 comment added Noah Schweber @Andreas, good point. Edited.
Oct 15, 2012 at 1:05 comment added Andreas Blass What you wrote about countably closed forcing applies more generally to any forcing that doesn't add reals (since that's all you used from the "countably closed" hypothesis) --- and there are forcings that don't add reals but aren't countably closed, for example the standard forcing to add a club subset in a statinoary, co-stationary subset of $\omega_1$.
Oct 15, 2012 at 0:51 answer added Joel David Hamkins timeline score: 8
Oct 14, 2012 at 22:00 history edited Noah Schweber CC BY-SA 3.0
Incorporated comment
Oct 14, 2012 at 21:58 comment added Noah Schweber (Sorry, I screwed up my quotation marks: 'has property $P$."' should be 'has property $P$.""')
Oct 14, 2012 at 21:57 comment added Noah Schweber Good points. One thing that might be doable is to ask when a theorem of the following form is provable in ZFC (+ large cardinals?): "$Det(\Gamma)\implies$ "if $\mathbb{P}$ is any poset such that $\Vdash_\mathbb{P} $"$Det(\Gamma)$", then $\mathbb{P}$ has property $P$." This is expressible in the language of ZFC, since forcing is definable, as long as $\Gamma$ is a sufficiently nice pointclass. Would this work?
Oct 14, 2012 at 20:54 comment added François G. Dorais Statements like $(\ast)$ are always tricky to formulate. I think you need some more qualifiers on the transitive model $W$. As is, we could take a large $W$ where $\mathbb{P}$ is countable and then everything falls apart. But that's not really an answer since things probably fell apart in $W$ before forcing with $\mathbb{P}$. Working inside a fixed universe $V$ would help but then the assumptions of $(\ast)$ are likely to need more large cardinal power than what you intended.
Oct 14, 2012 at 20:17 history edited Noah Schweber CC BY-SA 3.0
Fixed grammar
Oct 14, 2012 at 19:56 history asked Noah Schweber CC BY-SA 3.0