Characterizing stability and superstability by unions of chains and saturated models
نویسندگان
چکیده
We show that the non-superstability (non-stability) of a theory T is equivalent to the condition that for every elementary chain of length u; (un) of saturated models Mi of T with ||M,+i|| > ||M;|| for all s < UJ(U/I), the union of the chain is not saturated. The cardinality of T is immaterial.
منابع مشابه
Equivalent Definitions of superstability in Tame Abstract Elementary Classes
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