Theorem: Construction of Groups from Commutative and Cancellative Semigroups

Let \((H,\circ)\) be a semigroup, which is commutative and cancellative. Then there exists a unique group \((G,\ast)\) with the following properties:

  1. There is a subset \(S\subset G\), which is a semigroup isomorphic to \(H\), i.e. where \((S,\ast)\simeq (H,\circ)\).
  2. There is a subset \(S\subset G\), which is a semigroup isomorphic to \(H\), i.e. where \((S,\ast)\simeq (H,\circ)\).

Proofs: 1

Parts: 1
Proofs: 2


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References

Bibliography

  1. Kramer Jürg, von Pippich, Anna-Maria: "Von den natürlichen Zahlen zu den Quaternionen", Springer-Spektrum, 2013