Model Theory without Choice? Categoricity Sh840
نویسنده
چکیده
We prove Los conjecture = Morley theorem in ZF, with the same characterization (of first order countable theories categorical in אα for some (equivalently for every ordinal) α > 0. Another central result here is, in this context: the number of models of a countable first order T of cardinality אα is either ≥ |α| for every α or it has a small upper bound (independent of α close to i2). The author would like to thank the Israel Science Foundation for partial support of this research (Grant No.242/03) and Alice Leonhardt for the beautiful typing. First Typed 04/Feb/18 Latest Revision 08/July/4 Typeset by AMS-TEX 1
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تاریخ انتشار 2011