摘要

A group G is said to be rigid if it contains a normal series G = G (1) > G (2) > . . . > G (m) > G (m+1) = 1, whose quotients G (i) /G (i+1) are Abelian and, treated as right a"[G/G (i) ]- modules, are torsion-free. A rigid group G is divisible if elements of the quotient G (i) /G (i+1) are divisible by nonzero elements of the ring a"[G/G (i) ]. Every rigid group is embedded in a divisible one. Previously, it was stated that the theory oe"u (m) of divisible m-rigid groups is complete. Here, it is proved that this theory is omega-stable. Furthermore, we describe saturated models, study elementary submodels of an arbitrary model, and find a representation for a countable saturated model in the form of a limit group in the Fra < ss, system of all finitely generated m-rigid groups. Also, it is proved that the theory oe"u (m) admits quantifier elimination down to a Boolean combination of is not an element of a integral-formulas.

  • 出版日期2018-3