Difference between revisions of "Lower attic"

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* Up to [[The middle attic]]
 
* Up to [[The middle attic]]
  
* The ordinals of [[infinite time Turing machines]], such as
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* The ordinals of [[infinite time Turing machines]], including 
** [[infinite time Turing machines#Sigma | $\Sigma$]], the supremum of the accidentally writable ordinals
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** [[infinite time Turing machines#Sigma | $\Sigma$]] = the supremum of the accidentally writable ordinals
** [[infinite time Turing machines#zeta | $\zeta$]], the supremum of the eventually writable ordinals  
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** [[infinite time Turing machines#zeta | $\zeta$]] = the supremum of the eventually writable ordinals  
** [[infinite time Turing machines#lambda | $\lambda$]], the supremum of the writable ordinals,  
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** [[infinite time Turing machines#lambda | $\lambda$]] = the supremum of the writable ordinals,  
 
* [[admissible#relativized_admissible | $\omega_1^x$]]
 
* [[admissible#relativized_admissible | $\omega_1^x$]]
 
* [[admissible]] ordinals
 
* [[admissible]] ordinals

Revision as of 21:27, 27 December 2011

Welcome to the lower attic, where we store the comparatively smaller notions of infinity. Roughly speaking, this is the realm of countable ordinals and their friends.