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Inner models with large cardinal features usually obtained by forcing
We construct a variety of inner models exhibiting features usually obtained
by forcing over universes with large cardinals. For example, if there is a
supercompact cardinal, then there is an inner model with a Laver indestructible
supercompact cardinal. If there is a supercompact cardinal, then there is an
inner model with a supercompact cardinal \kappa for which 2^\kappa=\kappa^+,
another for which 2^\kappa=\kappa^++ and another in which the least strongly
compact cardinal is supercompact. If there is a strongly compact cardinal, then
there is an inner model with a strongly compact cardinal, for which the
measurable cardinals are bounded below it and another inner model W with a
strongly compact cardinal \kappa, such that H_{\kappa^+}^V\subseteq HOD^W.
Similar facts hold for supercompact, measurable and strongly Ramsey cardinals.
If a cardinal is supercompact up to a weakly iterable cardinal, then there is
an inner model of the Proper Forcing Axiom and another inner model with a
supercompact cardinal in which GCH+V=HOD holds. Under the same hypothesis,
there is an inner model with level by level equivalence between strong
compactness and supercompactness, and indeed, another in which there is level
by level inequivalence between strong compactness and supercompactness. If a
cardinal is strongly compact up to a weakly iterable cardinal, then there is an
inner model in which the least measurable cardinal is strongly compact. If
there is a weakly iterable limit \delta of <\delta-supercompact cardinals, then
there is an inner model with a proper class of Laver-indestructible
supercompact cardinals. We describe three general proof methods, which can be
used to prove many similar results
Superstrong and other large cardinals are never Laver indestructible
Superstrong cardinals are never Laver indestructible. Similarly, almost huge
cardinals, huge cardinals, superhuge cardinals, rank-into-rank cardinals,
extendible cardinals, 1-extendible cardinals, 0-extendible cardinals, weakly
superstrong cardinals, uplifting cardinals, pseudo-uplifting cardinals,
superstrongly unfoldable cardinals, \Sigma_n-reflecting cardinals,
\Sigma_n-correct cardinals and \Sigma_n-extendible cardinals (all for n>2) are
never Laver indestructible. In fact, all these large cardinal properties are
superdestructible: if \kappa\ exhibits any of them, with corresponding target
\theta, then in any forcing extension arising from nontrivial strategically
<\kappa-closed forcing Q in V_\theta, the cardinal \kappa\ will exhibit none of
the large cardinal properties with target \theta\ or larger.Comment: 19 pages. Commentary concerning this article can be made at
http://jdh.hamkins.org/superstrong-never-indestructible. Minor changes in v
Set-theoretic problems concerning Lindelof spaces
I survey problems concerning Lindelof spaces which have partial set-
theoretic solutions
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