Nonsurjective epimorphisms in decomposable varieties of groups
نویسنده
چکیده
A full characterization of when a subgroup H of a group G in a varietal product NQ is epimorphically embedded in G (in the variety NQ ) is given. From this, a result of S. McKay is derived , which states that if NQ has instances of nonsurjective epimorphisms, then N also has instances of nonsurjective epimorphisms. Two partial converses to McKay’s result are also given: when G is a finite nonabelian simple group; and when G is finite and Q is a product of varieties of nilpotent groups, each of which contains the infinite cyclic group. Section
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