THE SUBGROUP MEASURING THE DEFECT OF THE ABELIANIZATION OF SL2(Z[i])
نویسنده
چکیده
Abstract There is a natural inclusion of SL2(Z) into SL2(Z[i]), but it does not induce an injection of commutator factor groups (Abelianizations). In order to see where and how the 3-torsion of the Abelianization of SL2(Z) disappears, we study a double cover of the amalgamated product decomposition SL2(Z) ∼= (Z/4Z) ∗(Z/2Z) (Z/6Z) inside SL2(Z[i]); and then compute the homology of the covering amalgam.
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