Can We Identify Quotient Groups as Subgroups of the Original Group?

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SUMMARY

The discussion centers on the identification of quotient groups, specifically whether G/M can be recognized as a subgroup of G/N when N and M are normal subgroups of G with N ≤ M. The approach involves seeking a homomorphism from G to G/N with kernel M, although the author struggles to find such a homomorphism. The exploration aims to establish a more specialized result regarding nilpotent quotients and maximal p-quotients, highlighting the need for specific automorphisms that differentiate the actions of G/M and G/N on their respective subgroups.

PREREQUISITES
  • Understanding of group theory concepts, specifically normal subgroups and quotient groups.
  • Familiarity with homomorphisms in the context of group theory.
  • Knowledge of nilpotent groups and p-groups.
  • Experience with automorphism groups and their properties.
NEXT STEPS
  • Research the properties of nilpotent groups and their quotients.
  • Study the structure of maximal p-groups and their significance in group theory.
  • Explore the concept of homomorphisms and kernels in greater depth.
  • Investigate automorphisms in group theory, focusing on examples with non-trivial structures.
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Mathematicians, particularly those specializing in abstract algebra, group theorists, and students seeking to deepen their understanding of quotient groups and their relationships within group structures.

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Let G be a group and let N\trianglelefteq G, M\trianglelefteq G be such that N \le M. I would like to know if, in general, we can identify G/M with a subgroup of G/N.

Of course the obvious way to proceed is to look for a homomorphism from G to G/N whose kernel is M, but I can't think of one.

What I actually want to show is a more specialized result (namely the case when finite G/N is the nilpotent quotient of G and G/M is a maximal p-quotient of G for some p dividing the order of G/N) but the above is a lot cleaner and didn't yield obviously to a proof or counter-example so I thought I'd explore that first.
 
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I would look for a counterexample, although I found none as the small groups are all "too cyclic". We have
$$
M\rtimes G/M \cong G \cong N \rtimes G/N\text{ and } N \triangleleft M
$$
This means we have to look for the automorphisms and need a group, where ##G/M## operates differently on ##M## than ##G/N## does on ##N##. Therefore we need automorphism groups which have a few elements to select from.
 

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