Strong dichotomy of cardinality

Saharon Shelah

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arXiv · math/9807183

Strong dichotomy of cardinality

Saharon Shelah

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Abstract

A usual dichotomy is that in many cases, reasonably definable sets, satisfy the CH, i.e. if they are uncountable they have cardinality continuum. A strong dichotomy is when: if the cardinality is infinite it is continuum as in [Sh:273]. We are interested in such phenomena when lambda = aleph_0 is replaced by lambda regular uncountable and also by lambda = beth_omega or more generally by strong limit of cofinality aleph_0 .

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Saharon Shelah. 1998-07-15. Strong dichotomy of cardinality. https://arxiv.org/abs/math/9807183

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