Difference between revisions of "Middle attic"

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* into the [[upper attic]]
 
* into the [[upper attic]]
 
* [[correct]] cardinals, [[reflecting | $V_\delta\prec V$]] and the [[reflecting#Feferman theory | Feferman theory]]
 
* [[correct]] cardinals, [[reflecting | $V_\delta\prec V$]] and the [[reflecting#Feferman theory | Feferman theory]]
* [[reflecting#Sigma2 correct | $\Sigma_2$ correct]] and [[reflecting | $\Sigma_n$-corrct]] cardinals
+
* [[reflecting#$\Sigma_2$ correct cardinals | $\Sigma_2$ correct]] and [[reflecting | $\Sigma_n$-correct]] cardinals
 
* [[beth#beth_fixed_point | $\beth$-fixed point]]
 
* [[beth#beth_fixed_point | $\beth$-fixed point]]
 
* the [[beth]] numbers and the [[beth | $\beth_\alpha$ hierarchy]]
 
* the [[beth]] numbers and the [[beth | $\beth_\alpha$ hierarchy]]

Revision as of 19:57, 22 July 2013

St. Augustine Lighthouse photo by Madrigar

Welcome to the middle attic, where the uncountable cardinals, that solid stock of mathematics, begin their endless upward structural progession. Here, we survey the infinite cardinals whose existence can be proved in, or is at least equiconsistent with, the ZFC axioms of set theory.